How do I bring an old bike up to speed? I'm an adult that is new to biking due to a triple whammy of a childhood aversion to effort, my family moving to a town on the side of a mountain with steep roads, and my bike getting run over by a neighbor (I gave up riding around age 10).

I didn't buy another one until my wife got me involved riding with her.

I bought it from a guy on Craigslist.  He's had it in a storage unit for at least fifteen years, though possibly more.

The thumb shifters are unlabeled and don't have set stopping points for the gears. I can rotate the lever all the way around a 200 degree arc, the chain switches gears depending on where they're pointing.  They seem to have hints of rust on them.

The bike rides fine, though there is a slight grinding while pedaling unless I get the shifters just right, but as I can't tell where to stop them, this is difficult.

My wife loves to ride and I want to get better at it so we can enjoy it together, I'm just worried that my bike isn't safe.

What can I do to make sure it's safe and reliable?  I know nothing's been oiled or maintained for the previously mentioned time period or since I've bought it.

It's a KHS, so it could be as old as 36 years, but I really have no idea how old it is.

UPDATE -

I took a bunch of pictures.  I hope they can help you identify things better.
Sorry about how much scrolling is required!

Restoring the bike is a great way understand the bike.

My history is similar to yours. Gave up bikes around 10. Wife want to me ride with her.

I got a top of the line bike on CG for peanuts. of course, it was top of the line around the 90s :)

cleaning

start by REALLY cleaning the bike. simple green and brushes. don't be afraid to wet the bike. just avoid the seat if it's leather. and no water inside the tubes.

shifters

I'd start replacing the shifters for indexed ones. getting the same brands will usually work. but will require a lot of research to match them with the rear derraileurs (the gear shifting thing on the back).

Another option is to just keep the ones you have (friction shifters) and feel the gears changing. Even with modern bikes, this is still the norm with the front gears, so no harm on going that route also. Plus, restoring and fine tunning the bike your self will make you 'know' how to feel the gears better.

UPDATE: i take that back. i kept my friction ones on my bike and rode the wife's bike with cheap indexed ones a few times. the friction are way better. also when the freewheel needed replacement i can get any number of gears i feel like and don't worry :). Indexed ones are better for changing on a whim. but are either freaking expensive or will require constant fiddling. friction are just install and forget. love them. unless you go expensive indexed. but i'm a cheap bastard.

Wheels

if it has Sealed bearings in the middle of the wheel you are fine. Those last a life time. It's that axle on each wheel. just turn them. if they keep rotating without ratling noises, you are fine. if they just turn a couple times after you roll them with your hand. you need new ones.

also, if they wooble when you turn them. they need truing. that's the only skill that does not pay off to learn your self.  $15 at a bike shop and the wooble is gone.

If they rattle, dont' spin, wooble. just get new wheels.

cables

inspect them all. pull them with your hand via each housing. if there's any drag. try to fix it (i did fix my rear derraileur cable by cutting one broken thread that was pointing outwards and so dragging in the housing. good as new now). If it's a brake cable, spew out the $7 and get a new one with new housings.

WD-40 into all cable paths also help.

brakes

Begin by checking that they still have plent of rubber.

Also check your wheel rims for damages.

you have to loose them and tighten them as close as possible to the rim. in a way that they are slightly curved against the wheel, with the BACK of the brake touching the wheel. the front of the brake is the front of the bike. it should look like: \ || /
you should be able to touch the rim with some <15% of travel of the brake. the rest of the travel should be extra pressure for breaking power. Play around a lot with this. there's several places where you can adjust your brake.

Second step is to adjust them in a way that when you press the brakes, both sides touch the wheel at the same time! there's usually a screw on the side to control that.

make sure that NO other cable housing goes UNDER the front brakes cable.

And I can't stress this enough: test drive the bike on a straight run EVERY time you adjust them. mostly now that you are getting to know things.

bearings

bike has serviceable bearings in the cranks and in the freewheel (the thing that rotates the back wheel when you are not pedaling). usually your freewheel will be dry, cranks are almost always fine. check it by rotating the wheel and leaving the cranks still. if the chain is dragged to the front at slow rotating speeds, you have to grease/change the freehweel. I'd only change if the cogs are worn out.

you will need a spanner tool to open those.

derraileurs

You will hear about them a lot. it's the pair of gears on the back that change the drive gear on the rear wheel, and the guide on the front that change the drive gear on the cranks.

It the easiest part to restore and adjust. If they do not move sideways when you press with your hands, open them up, clean, and grease the hell out of them. It's easy. was what took less time for me. but everyone will say the opposite.

when they are moving easily when you press them, read the parktool's article on how to adjust it. http://www.parktool.com/blog/repair-help/rear-derailler-adjustments-derailleur

more

There's probably more than I can remember now... but all in all it took me around a week and a half. And around $50 in tools/greases/new chains. I didn't have to replace any component or cable yet. And now i love to ride. I go to work every day riding.

now, to fully understand what you are doing, read:

http://sheldonbrown.com/

http://www.parktool.com/blog/repair-help

The last link will point you to several expensive tools. I only need them to work on the cranks and remove the freewheel (you don't have to remove the freewheel unless you will replace it, i didn't know it back then). I got the tools asking around at work, one guy had a nice kit i could borrow.

Excellent pictures! You've said that this bike has not had regular maintenance. This is critical. I love old bikes. I love Suntour! But, frankly, you could buy a lightly used bike from CL, with similar characteristics - and MUCH better components, for far less than it is likely to cost you to refurb this bike. And, you will be much happier with the newer bike.

For instance, from looking at the photos - your middle chainring looks worn. This means your chain is likely worn out also. My guess is both are likely in need of replacement. Everything certainly needs maintenance, and it needs way more than a Simple Green cleanup. The problems you describe with the shifters do not sound good - and I think you may end up wanting to replace the shifters. But quality replacements for those shifters today are not so easy to find.

My best advice is to talk to a local bike shop - or even two of them. Ask them what they think needs to be done. Then ask yourself if you are up to doing that work instead of them.


cancer survivor and fitness I am a two-time cancer survivor ...head/neck and lung (they removed a lobe in the second instance) ... I have been biking for a couple of years now (I bought a fixie, since it was cheap and I wasn't sure I would be able to cut it), and I try to ride three or four times a week, but in the range of 5-8 miles each session.  I like to think this is helpful in terms of overall fitness and breathing, but haven't found anything to confirm this. Always trying to expand on distance, but so far stuck in this range.
 Thoughts?

A perfectly reasonable question.

Cycling is gererally thought of as being an excellent way of keeping fit. It is seen as beneficial for cardio- health and for leg muscles (not so much for arms), and is low-impact on joints. On top of that I would add that the benefits are proportional to the amount of effort you put into it.

Of course, how safe this exercise is for the individual would depend on the individual themselves, their existing fitness etc. and any pre-existing medical conditions. An individual should discuss any proposed fitness regime with their doctor. So where your question becomes impossible to answer is how reasonable your fitness regime is for you, and any improvements you could make. But that holds true across the board.

The human body is amazing
Although cancer is a tragedy, but in the face of pain, be sure to maintain a happy mood
Cycling is a very good event, it does make people happy life. Riding in the process can be a lot of insight into the views, it is also conducive to thinking, which for your disease will be a good help.
Please keep a happy mood every day, bless you


How does lubricating your chain help protect your cassette and chainrings from wearing too? I just got my mountain bike back from the shop after a frame warranty, and they replaced my chain as it was apparently worn (2x11). They recommended changing the cassette and chainrings while I was at it, but I wanted to inspect those myself before making those relatively expensive changes.
That got me to think: how does lubricating the chain stop the cassette and chainrings from wearing? You’re not supposed to cover the cassette nor chainrings in lube, so what is preventing them from wearing?
In my case, I noticed that some of my favorite cogs had their contact faces deformed. There was a slight burr where the chain contacts the cog. On the other hand, the big chainring (my favorite) showed significant wear. I’m not surprised by this, considering the occurrence of chainring strikes and shifts under big power, but in some spots I’m pretty sure there’s shavings of metal missing. This corroborates to the fact that I now experience chain slippage every so often when using the new chain. This surely can’t be normal, what am I doing wrong?
I’ve only had the bike for 900km too, and I’m pretty good when it comes to cleaning and lubing. My drivetrain is Shimano SLX M7000 if it matters.

In the ideal case, the chain will not actually be rubbing significantly against the chainrings under load. As the chain wears, the spacing between the chain links becomes different from the tooth spacing, and this difference in spacing means that there is sliding contact as the teeth engage the chain.
The rollers inside the chain help to convert some of this sliding motion into rolling friction (transferring the actual sliding contact to the more protected and better lubricated internal joints of the chain), but any binding of these rollers against the pins again leads to sliding contact between the tooth and the chain.
Keeping the chain lubricated (and, as noted in the question comments, clean) will both minimize the wear that stretches the chain and prevent roller binding, thus reducing the wear on the teeth.

I just got my mountain bike back from the shop after a frame warranty, and they replaced my chain as it was apparently worn (2x11). They recommended changing the cassette and chainrings while I was at it, but I wanted to inspect those myself before making those relatively expensive changes.

Choose a different shop the next time. There is absolutely no reason to change the chainrings when changing the chain. In fact, the converse is true: if you change the chainrings, you MAY need to change a worn chain to a new one.
The rule is that a new driving component may not drive a worn driven component. So everything rearwards MAY need to be changed. So,

If you only change a cassette, you're fine
If you change a chain, you MAY need to change the cassette
If you change a chainring / chainrings, you MAY need to change the chain, which MAY necessitate you to change the cassette as well

Note the word "may". Only testing will reveal if the chain skips.
Thus, reputable bicycle shops do a test. If changing a chain, they don't blindly suggest changing the cassette as well, but rather test whether the chain skips on the worn cassette.

how does lubricating the chain stop the cassette and chainrings from wearing?

If the chain is not lubricated, it wears rapidly. A worn chain has longer link spacing, thus not driving a cassette sprocket perfectly. The load on the cassette sprocket teeth is concentrated on one tooth, quickly altering the shape of the tooth to be such that it only works with the existing worn chain and no longer works with a new chain. This effect is largest on the most-used sprockets and smallest sprockets.
If the chain is lubricated, it wears less rapidly (assuming you clean the chain prior to re-lubrication and only re-lubricate if the chain clearly needs more lubricant, i.e. it is starting to squeak).
A chain excessively lubricated will carry dirt from the outside of the chain to the innards, wearing the chain very rapidly.
Thus, the golden middle path is to lubricate only a chain that clearly needs lubricant, clean it before lubrication, and wipe the excess lubricant away so that the excessive lubrication does not cause rapid chain wear.

You’re not supposed to cover the cassette nor chainrings in lube, so what is preventing them from wearing?

It's the chain wear that wears the cassette and the chainrings. The chainring wear is not dangerous but the cassette wear is. When changing a worn chain, you may need to change the cassette or some of its individual sprockets. You almost never have to change chainrings.

This corroborates to the fact that I now experience chain slippage every so often when using the new chain. This surely can’t be normal, what am I doing wrong?

You (or the shop) caught chain wear too late. Replace the chain earlier, and the sprockets are more likely to work with a new chain.
So you in this very special case need to replace the cassette as well, but not the chainrings. For the new chain, purchase a Shimano TL-CN42 chainwear indicator. The Shimano wear indicator is the only accurate wear indicator I'm aware of. All of the others are complete and total garbage and not worth spending money on. See this explanation for details.


Where to mount a headlight if the handlebar is obscured by a basket I have a permanently mounted basket in front of the handlebars (because I have a child seat on the rack in the back). I also have a headlight on the handlebars (this one, if anyone cares). If the basket is empty, it is somewhat visible, through the mesh that basket is made of. However, if I put anything in the basket, the headlight is useless.

I should mention that I also have a dynamo powered headlight below the basket, but I turn it on only when it's really dark, as the bottle dynamo noticeably slows down the bike.

Any ideas where to move the headlight from the handlebars? To the fork perhaps? That can be a problem as it would point a bit upwards then, and also would be partially obscured by the wheel itself.

Something like this accessory is what you need:

Can be fitted onto wired or meshed bicycle baskets.
This specific model is made by the "Rixen & Kaul" and can be found in many online shops. E.g. Amazon - Rixen & Kaul Light-Clip Basket Fitting - Black.

There is still no solution.
[1] The KLICKfix accessories do not work.  They look good, but the lamp vibrates as you ride, causing stress where the KLICKfix meets the basket and eventually the vibration causes it to cut through your wire basket.  I've had two wire baskets damaged like this.
[2] The Electra LED lights are too feeble.
[3] Attaching a pipe with PVC is a pretty clunky solution.
What's needed is a mount which could attach to the bottom of the basket, either above the bottom, or under it. The problem is that each lamp manufacturer's mount is different, so if Smart (e.g.) designed a mount to attach to the base of wire baskets, it would only fit Smart lights. So it would be uneconomic to manufacture.
I don't know what the answer is.


Is it necessary to buy a special tool to open the chain lock I've installed a chain lock to my chain. It looks like this (mine is not KMC):

Now I need to unlink the chain to clean it, but I can't do it: the lock is too tight. I found a special tool on ebay to open such locks:

http://www.ebay.com/itm/KMC-Missing-Link-Removal-Tool-Fast-and-Effective-Black-/171101004843?pt=AU_Sport_Cycling_Parts&hash=item27d66a242b

Is it the correct tool to open the chain lock?
Is it possible to open it using home tools?

That is the appropriate tool to open KMC (and similar) style missing links.
It is possible to open them with some needle nose pliers but is much easier with a missing link removal tool and you are less likely to damage the chain (or yourself.)

I don't think I've ever disassembled one of these missing links, since they became common.  I've always used a chain press.  Have you considered using one of those?  You need one if you want to shorten or lengthen the chain anyway.


Is there a difference of spacing between cogs on a 7 speed cassette vs a 8 speed cassette? Is there a difference of spacing between cogs on a 7 speed cassette vs a 8 speed cassette?

When I got a new wheel (upgrade from freewheel hub), I tried to get a 7 speed cassette (SRAM) for it, but the local shop didn't have the spacers for the hub.  Instead I swapped it out for a 8 speed cassette (SRAM), but kept the 7 speed shifters (shimano EF-51).  I have a few gears in the lower and middle gears where the chain constantly tries to jump between.  The higher gears are fine.  The issue mostly went away when the tension on the cable was adjusted, but not completely.  I noticed it may have moved the issue to another part of the cassette.

Update Soon after posting this I replaced the cassette with a proper 7 speed and all the issues went away.

Yes, there is. Shimano/SRAM & compatible seven speed is 5mm cog-to-cog, and eight is 4.8mm. Generally what you're trying to do here can't be made to work very well. There are some tricks that without any additional parts can increase the movement of the derailer, but not decrease it. Also if you have a true 7-speed-only chain (not common anymore but they exist, KMC Z50 is one example) it won't work well on 8.

A shop not having anything to offer to make the conversion work is pretty unfathomable. The "correct" spacer is a 4.5mm one, but the only thing that makes it correct is that's the number that locates the cassette exactly where an actual Shimano 7-speed hub would, so you could theoretically swap wheels without adjusting the derailer. Any other stack of correct internal diameter spacers in the 4-5mm or so range will still work, so if this shop was too new-stuff-oriented to have a 7->8 spacer, they should just sell you a 2.5mm bottom bracket spacer (ubiquitous modern shop item) plus a 1.8mm 10->11 hub spacer (ubiquitous modern shop item). That will work perfectly.

all chains up to 8 speed are the same width as is the distance between the cogs, regardless of make or actual number of gears until you go to a 9 speed cassette. your problem is probably not due to the number of gears, but due to wear, damage or mis-adjustment.

I am a BBI certified bicycle mechanic who has been working in shops since the 1990's.


Why are there metal shavings in my brake pads? I have several brake pads on my cantilever brakes that have several small metal shavings embedded in the pad.  Is this normal?  What should I do about it?

This is normal to some extent - brake pads have to be made of soft material which wears down on the rims (and conversely, the rims wear down into the brake pads to some extent) in order to stop you. This means the pads pick up grime and bits of metal from the rims and road and stuff which embed into the pads and in turn wear down your rims / reduce braking efficiency. If they're eating large portions of metal, then you should probably switch the pads to ones made of different material (anecdotal evidence suggests the pads which come with most cheaper brakes belong in the trash).

I'd start with a high quality pad (e.g. Koolstop Salmon pads), and making sure the rims are clean (use citrus degreaser/rubbing alcohol). Mavic and some others make special blocks for cleaning and (slightly) sanding your rims as well, which you can use (but definitely not necessary).

If you do get metal or other contaminants in your pads though, you can pick it out with tweezers and buff the pads with some fine sandpaper (remove the grit afterwards!). Make sure the pads have sufficient material leftover after this - if the metal backing comes through, your rims are going to take damage.

Also, make sure your brakes are properly adjusted: http://sheldonbrown.com/canti-trad.html
http://www.parktool.com/blog/repair-help/cantilever-brake-service is a good link to look at as well (Specifically see the "Pad Wear" section). If your brakes are rubbing on the brake tracks, you'll pick up more cruft (and wear out your rims), for example.

Also, check your rim wear indicators (if you have them - they're reasonably common on modern rims) to make sure that you're not too worn on the rims as well (this is typically a little groove which should be there on the rims, but can appear in other forms such as something that appears when the rim is too worn out). If you don't have them, you can try a procedure like http://archive.ctc.org.uk/resources/Magazine/20011163.pdf. If the rims get too worn, they break and you end up hurt (probably).

It is unlikely, but remotely possible that some brake pads might even contain some metal, which is the case with car brake pads.


What are the advantages of owning a Unicycle? What are the advantages of owning a Unicycle, as opposed to owning a bicycle?

I can think of several:

They are lighter and smaller than bikes
Easier to maintain, fewer moving parts
They provide good practice for balancing

Presumably a 50% reduction in punctures?

Unicycling helps you get in touch with balance. Thank god for them.


Any luck using a 2 or 3 jaw puller to remove crank arms off a taper bb? Is there anyone who has had luck using a 2 or 3 arm crank puller to remove the crank arms off a tapered bottom bracket?

While Chris Dottavi mentionned that jaw pullers are not meant to remove crank arms, they can definitively used for that, although you might want to think bit before doing so.
I do work in a community bike workshop, where we have a lot of people comming with bicycles that can be quite old or in bad shape. It is therefore not always possible to use the usual crank puller. Therefore, we sometimes have to do otherwise. For the sake of completeness, here is the list of things I have done, in order of preference.
For recent (squared) bottom brackets:

try with a regular crank puller, if you have the right one (check the standards, in particular if you have an odd bike).
try with a jaw puller. Depending on the jaw puller and the shape of the star of the right crank, it might be more or less easy to grab it (for instance, if you have a "5 leg" spider to hold the crankset, it might be difficult to place the tool if you use a 2 jaws puller). Also, depending on the end of the screw of the puller, you might want to keep the crank screw (just unscrew it for a few turn). Indeed, if the screw of the puller is to small, it can destroy the threading of the axle (happens almost never, but not never). The main advantage of that technique is that, if you are careful, it most likely preserves the crank (assuming you are interested in keeping the crank, e.g. if you did not have the right crank puller).
unscrew the crank screw, and go for a ride. I rarely do that, since it might require some time (and, at the workshop, we can not really say: "take a ride and come back"), but it most likely work, often quickly. Some drawbacks: if you have aluminum cranks (most likely on modern bikes), you do not want to ride with the loosen crank: the squared shape hole will quickly not be that square anymore (once again, if you intend to reuse the crank).
with a torch, you can warm the crank, so that it expands (faster than the axle). I've done that only once, so I can not really tell some advices
Finally, if, with all that, the crank is still tight, you can cut it with an angle grinder. Take care of where you cut, as you do not want to cut the axle or the frame. I usually do three cuts. This is really last resort: the crank is (of course) not reusable, but it is also quite likely that the axle get damaged too, sometimes the cup too. While wuite extreme, this is sometime the only way to recover some frames.

For older (cotter) axles/cranks:
You should not have any problem with those, once the cotter is removed. If you have, you can hit (gently) the crank with a hammer, or use a jaw puller.

No, 2 or 3 jaw pullers are not meant for removing cranks off a tapered BB axle.
I recommend going to a local bike shop and asking them for a tool to buy or what tool so you can buy, or just ask them to do it for you.


I need help identifying used MTB tire sealant I have a new-used MTB and I don't know what kind of sealant is in its tires. Does anyone know what this may be, or have a good resource for figuring it out?

The liquid sealant in the tire is a light brown, like coffee with milk. The dried sealant is a slightly darker brown.

The final result was "don't do that" (where "that" was to try to identify and match the existing sealant). Per advice in the comments I cleaned out the remaining liquid sealant (and the crud where the sealant had pooled and hardened during non-use), cleaned the inside with isopropyl alcohol and a lint-free towel, and then set the tires up with the sealant I have on hand (Stans). They have been holding pressure and riding great.

The tyre manufacturer would hopefully recommend a sealant for use with their tyres - that's the case with my tubeless tyres.

Looking up the brand & model is probably a good place to start.


Why is it important to have good saddles? Why is it important to have good saddles? Other than the comfort in long rides.

Taken from the livestrong website:

A March 2005 article in "European Urology" discusses the overuse injuries that can stem from long-term bicycling. The article states that, although cycling can be a healthy, beneficial sport, some injuries can occur to the urogenital system. Genitalia numbness was found to be most common, reported in 50 to 91 percent of the cyclists, followed by erectile dysfunction reported in 13 to 24 percent.

Prevention/Solution

Although studies do not link bicycling with specific prostate diseases, the pressure of traditional seats can create problems for both men and women. Fortunately, there are several types of seats that can help alleviate that pressure and prevent injury. Look for seats with a split saddle, or one with a space in the area that would normally press into the perineum. There are more extreme options like the "no-nose" bicycle seat, the moon seat and the easy seat that are geometrically different from a standard saddle.

The saddle isn't just a point of contact for riding, it also gets to lean against walls when the bike is parked and maybe against the ground/floor (if the bike is in the ownership of a youngster).

Naturally road bikes do not get thrown to the ground every five minutes, but, a BMX, or other child's bike, will. For this reason it is horses for courses, a quality seat for a BMX doesn't have to be comfy at all, a quality seat on a touring bike should not come apart when someone tries to lift the pannier-laden bike by the seat and a quality seat on an entry-level hybrid bike should survive wall-park abrasion.

What amazes me is why there are something like 4096 different types of bicycle seat on the marketplace. Is that level of product diversity necessary?

As for that talk of 'erectile dysfunction' being promulgated by bike seats and cycling, there is no way that can be true with modern saddles in the use of healthy-weight riders. Any talk of 'erectile dysfunction' is to be instantly dismissed as General Motors propaganda, as disseminated by the old-fashioned car-driving journa-fogeys at The Sun.
Agree that old saddles had a problem as the pelvic bones were not supported, but you cannot get those older saddles anymore (unless you include the Brooks dead-cow and rivets efforts).


What are the differences between men's and women's bike frames? Why do women's bikes have a diagonal bar in the frame instead of a horizontal frame? Is this the only difference?

Sorry if this has been asked (but I cannot find it by searching) and I also just cannot think of a reason why.

Way back when safety bikes were becoming popular, women wore skirts. Skirt lengths were to the ankle. The dropped top bar made getting on possible while maintaining respectability. Women were considered too fragile to risk hitting the top tube, hence the slanted bar. The trend continued even long after women stopped riding in long skirts.

Modern WSD (women specific design) geometry differs from conventional bike geometry. The difference goes beyond just size. Whether it is needed depends on who you ask. While some women may be smaller than the average male, many are as tall; height is not the only issue. Many women have a different leg to torso ratio than the male average and the frames are built to fit that difference. This is not to say that a women needs a female specific frame or that a male wouldn't fit on a WSD frame. It all depends on the individual physical traits of the rider.

The difference in height between a 5'10" (178 cm) man and a 5'5" (165 cm) woman is 8%.

So if men and women have the same shape, and if their bikes have the same shape, and if the man's bike has 28-inch (700 cm) wheels, then the woman's bike should have 26-inch wheels.

However I've found that small-framed road bikes or hybrid bikes, claimed to be suitable for women, still have 28-inch wheels: which changes their shape, and how well they fit the rider.

26-inch wheels exist but seem to be more standard for "mountain bikes" than for road bikes.

A couple of inches can make a real difference to how well a bike fits the rider.

Instead of or as well as asking the difference between a "mens" and a "womens" bike, it might be accurate/important to ask the difference between bikes for taller and shorter riders.

  I also just cannot think of a reason why...

Apart from wearing a skirt, another reason seems to be so that her feet can touch the ground when she hops off the saddle at a stop, because of sitting too high to begin with, perhaps because of the wheels are bit too large.


FSA Omega MegaEXO Press fit BB 19mm removal (non standard BB86) Has anyone removed a 19mm spindle (Omega) Press fit bottom bracket without destroying it in the process?

I have watched http://www.fullspeedahead.tv/video/7006668/installation-of-megaexo-crankset-on and the tool mentioned #EE056 can't be found anywhere on the internet.

That link is now broken. The best places to look seems to be http://www.fullspeedahead.com/support/technical-information-instructions/

I am not even sure that is for the 19mm version rather than the standard 24mm.

I understand I can take a punch/screwdriver and hammer it out of my frame, but the BB only has 1000km on it and I would like to reuse it in the winter.

I contacted FSA and was told no tool exists for pressing/removing the 19mm BB. So I proceeded with the cave man approach:

I used a long 3/8" extension (female side against the BB bearing) and hammer to knock out the left side, it came out easy.

The right side was a challenge with the same setup (it would not budge) , I ended up punching the bearing out of the BB shell.

I got the rest of the shell out with a 22mm deep socket and a short 1/2" extension and the same hammer technique. I would advise using a large socket that fits as soon as you get one side of the BB out.

The bearings/bb does not appear to be damaged and could be reused.

Punching a bb out with a screwdriver or similar won't necessarily destroy it as long as you are careful.


Useful and accurate mapping websites: United Kingdom What are your favourite regional online websites or blogs relating to mapping or routing that you find useful and accurate.

See also: What are the most useful or interesting cycling-related websites or blogs?

Please vote up or down based on the accuracy/usability of these services and post one website link at a time.

CycleStreets
CycleStreets is a UK-wide cycle journey planner system, which lets you plan routes from A to B by bike. It is designed by cyclists, for cyclists, and caters for the needs of both confident and less confident cyclists.
The service looks to be free, however, funding issues are causing the site's development to be slow, and they accept donations.
The site is currently in beta, and has gaps in coverage. There's an iPhone app for the site, and an Android app was in development last year.
The most useful feature, the Journey planner provides information you would normally get from any free mapping service, turn-by-turn directions, journey time and distance.
It also gauges the quietness of the route based on how much of the journey is based on cycle paths and roads, provides an elevation profile and the ability to import your journey to Google Earth or export it to a GPS device

Bikely
Based on Google Maps, the site is geared towards user-contributed routes. While there is a good amount of content here covering the UK, bikely.com is slow and hard to use.


What kind of bike rack can go with this bike? I'm looking for a bike rack to put on my bike so that I can hookup the baby seat with the bike. However, I don't see anywhere on my bike where I can mount the front bracket arms of the rack to it (please see pic.1). There is place to mount the lower arms, though (as shown in pic.2). Pic.3 shows the whole bike.

Do you know which bike rack can go with this bike?

Your bike looks like it comes equipped with a full-suspension frame, and the suspension mechanism is located where one would usually attach the rack stays. This will make attaching a rear rack extremely difficult, and almost certainly less secure.

I don't recommend attaching a rear rack to this bike, particularly not one that will be holding a child seat.

Instead, you could look into a child trailer. (For more information on child seats compared to child trailers, have a look at this answer.) Please note that pulling a trailer with any full-suspension bike can cause problems (see the comments).

You might have some luck with a seatpost mounted rack.  You may need to raise the seat up a bit on your bike to get it to fit since it seems that there isn't much clearance there.  However, these seatpost racks are not strong enough to support a child seat, and with a single point of failure I wouldn't even attempt it. But as a rack for your bike for carrying other things, this would work.

As others have said, the fact that you have rear suspension makes it difficult to attach a rack since usually racks require 2 attachment points, which is hard (impossible??) when the back of the frame needs to move due to suspension.  As far as baby seats go, you might want to opt for the Kangaroo child seat which has the seat located between you and the handlebars.  Again for this, it looks as though you would have to move your seat up a bit.


Disc brake rotor size and forks strength I have been told that every fork has a maximum rotor size characteristic. For example, for my $75 Suntour this is listed as 185mm. The explaination that I have been given for this limitation is that any larger rotor will have significant chance of breaking the forks! That is, the braking force will be too high and the brake mount system will shutter.

Is this correct and precise information or is it just some legal insurance?

My guess is its not so much about the forks themselves breaking - I cannot imagine that sort of force can be generated by brakes when the forks themselves have to handle the forces generated in prangs etc that would easily exceed any braking forces..... Yep - forks break in a bad prang, but no one would buy forks that did not survive a moderate fall without damage

The failure point is most likely the mounting posts, or the wheel being loosened or even ejected by the brakes on a QR system (well known issue and one argument for through axles).

However, the idea that bigger disks give more braking and bigger forces is overly simplistic. A cheap setup with 200mm discs ridden by a 100pound wimp will not produce the same force as a top quality 160mm disc ridden by a guy with the weight and strength of a gorilla.....

I believe its most likely the manufactures covering themselves and weasel words to get out of warranty claims from guys who buy cheap shocks, put on the biggest brakes they can find and ride them on the biggest drops they can find - and then claim "It broke.......". The kind of guys that do this would not be seen dead on a bike with small discs.....

And the simple answer is because its a radial (turning around a fixed point) force then the calculation (centripetal) force requires the size of the circle to be squared (thats it multiplied by itself), so if you increase the virtual rotor size by 45mm (160 to 205) then you square the difference (45x45 = 2025) then the forces involved are going to be MUCH bigger at the centre point and at the periphery of the circle, in short if you dont follow the manufacturers guidelines then you may or may not cause the system (fork, hub, spokes, calipers, mounting, axle, pads, etc) to fail at its weakest point. Having had this happen to me at Fort William downhill course (it was the pads, that i ripped the pad material clean off the backing plate) that failed and I went over a rather large double jump a little (a lot) too fast and the results are one year on a case of tendenitis and a lot of physio.


Shimano roller brakes: differences between each model and interchangeability One of my bikes has mounted a Shimano Roller Brake (BR-IM35 FF in my case).
These brakes on my bike are basically not working anymore and I would like to replace them (it's not a cable issue. They were already bad when I bought the bike, I've never worried about greasing them and now they are null...)

My problem is now to find which one to choose. There's more than one version but I haven't found anywhere what is the difference between them (besides the price!). For example these websites have some examples:

https://en.hollandbikeshop.com/bicycle-parts-city-bike/bicycle-brakes/shimano-nexus-brakes/nexus-roller-brake/

https://bcbikeshop.dk/rullebremser

What I can guess is that the IM denomination comes from "Inter M":
https://bike.shimano.com/en-EU/technologies/component/details/shimano-inter-m

I've found these other discussion but no answer:
Difference between BR-IM and BR-C Shimano drum brakes?

And on the Shimano website there's no information whatsoever. I've even tried the spanish, american and japanese website :D. I've found googling only some assembly drawing like this one for my brakes: http://si.shimano.com/pdfs/ev/EV-BR-IM35-FF-2776.pdf

Does anyone have any idea?! Are they still on production?

And well, if you're ending up on this discussion, you'll find some information on the might Sheldon Brown page:
https://www.sheldonbrown.com/rollerbrakes.html

For all I know the roller brake mounting mechanism is the same for all the Shimano roller brake models and all use the same cable pull ratio.

Different (ly priced) models have different stopping power adn cooling (although none are recommended for long braking on descends etc).

Cleaning and regreasing them usually helps. Shimano roller brake grease works fine in my experience, although I suppose (haven't tested) that molybdenum disulfide grease from a store should work fine (NLGI 1 hardness seems apropriate).

Made a video showing how to dissassemble, clean and reassemble a roller brake (lubing is not shown).

There's also a long and detailed explanation of the Shimano roller brakes on Sheldon Brown website.

In Amsterdam and maybe even the UK, these are common but I don’t know if anyone from Amsterdam is on the forum to comment. I ride with Shimano nexus 8 (formerly used to be nexus 7) but I always get nervous when I take my bike for the annual maintenance as I almost always know the mechanics (for reasons above) recommended replacement vs rebuild. I don’t have enough space or time to do it myself.

Workcycles is a global supplier of Dutch bikes which have these systems so you may want to visit their site and contact a mechanic to get an understanding.

Hope that helps and good luck.


QR Skewer orientation Sheldon Brown's site suggests that QR skewers should be installed with the levers on the left side of the bike, "so the derailer [sic] doesn't interfere with it" and that "Usually, the lever for the front wheel also is on the left side, but some Bike Friday travel bicycles fold more easily if the handle is on the right side".
Most of my bikes now have disc brakes, and it seems better to install the levers on the right side so that there's no potential of the handle fouling the brake disk, however remote that possibility may be.
If I don't have any problems with the QR lever hitting the derailleur, is there any other downside to installing QR levers on the right side of the bike (drive side)?
https://www.sheldonbrown.com/skewers.html

This is one reason why we keep them on the left.

Most of my bikes now have disc brakes, and it seems better to install the levers on the right side so that there's no potential of the handle fouling the brake disk, however remote that possibility may be.

Disc brake bicycle should not use quick release. Quick release has been designed to withstand only forces that rim brake hubs encounter in their use. Disc brake discs are a fraction of the diameter of the wheel, so the force needed for any kind of reasonable braking is multiple times the weight of the cyclist. The disc brake reaction force tries to push the left end of the axle away from the fork dropouts. Normally, around 20% of the rider's and bike's weight is on the left front axle end, and when braking with rim brakes, around 50% of the rider's and bike's weight is there. Not only that, but with rim brakes the force always pushes the axle into the dropout, not out of the dropout. In these circumstances with disc brakes, if the quick release is even slightly loose, the fork will jump out of the axle and with no front wheel attachment anymore, you will fall.
This effect of disc brake trying to eject the wheel combined with the fact that the teeth of the quick release cannot stay still but will gradually wear away the material at the dropout due to the huge ejecting forces (that can be as much as 300% of the bikes's and rider's weight on the left front axle end in the ejecting direction as opposed to merely 50% of the bike's and rider's weight on the left front axle end in the non-ejecting direction with rim brakes), means the quick release due to dropout erosion gradually becomes looser and looser ... until it is so loose that the wheel ejects when braking hard.
So, given that most bikes today have disc brakes, the answer is that the QR skewer belongs to the garbage can, along with any flawed hubs that allow mounting brake disc on a quick release hub, and along with any flawed forks that have disc brake attachment while at the same time having a quick release hub attachment.
With rim brakes, I don't think the orientation of the QR skewer matters much. Put it in the way you prefer.


Need opinion on upgrading groupset for my road bike I just moved to UK for my masters and was looking for a road bike. I found a pretty old ribble 631 road bike taht was barely used. Its supposed to be around 20 years old but still has decals intact. The seller said that the bike was too large for him so he just used it on a turbo trainer. I paid £560 for it.
Rear derailleur - Shimano 105
Front derailleur - Shimano 600ex brand on
Brakes - Shimano 105
Brake levers - Shimano 105
Gear levers - Shimano index RX400
Rear cassette - shimano 12 - 24 ( 7 speed )
Wheels - Mavic MA3 rims on Shimano 105 hubs
Headset - Shimano 105
Stem - SR quill
Bars - Richey Pro T6
Seat post - Titanium with alloy layback clamp
Seat - San Marco Ponza
Tyres - Michelin axial sport
frame - ribble 631 reynolds road.

Although the bike is in pretty pristine condition, I am not used to downtube shifters.
The shifters are downtube, the front is friction, the rear is indexed. . I am thinking, I'd upgrade parts of the groupset, to a 10 speed cassette, bar end shifters and rear derailleur. The cost comes to another £250 if I source the items as cheaply as possible.
Here are my concerns -

Did I overpay for the bicycle ? I do have a feeling that I did :(
Should I spend the extra on the upgrades?

That's a nice enough bike, but it's not something to upgrade, you bought the wrong bike. Either you want a vintage bike in which case it sounds great, or you just want a road bike, in which case something with Shimano Claris R2000 would be suitable.
Assuming you have 400EX, then this dates from 1990-1992. 600EX would be pre 1988, so it's possible you actually have Exage Sport, which is more contemporary with 600EX.
631 tubing however suggests more 1990s than 1980s
I would suggest a value maybe £200? https://www.facebook.com/Retrobicyclesrecycle/posts/3754668234607817
There is nothing special about those components, though they aren't bad.
I had a look on fleabay and you could buy a generic modern(ish) bike such as a Triban 540 with 2x10 speed 105 and carbon fork for about £300. Or you could buy a new 2 x 8 speed bike such as the RC 120 for £400.
Not much to do with it except buy some new tyres if they've perished. Sell it if you don't like it. Buy a more suitable bike.

Did I overpay for the bicycle ? I do have a feeling that I did :(

Probably not. A new butted chromoly frame costs around 550 euros without the parts attached to it. If the frame is not broken, you paid just about right. About the only flaw I see in this frame of yours is that it uses a quill stem. Newer bicycles use an ahead stem. With this in mind, I'd say the frame is worth 350 euros. Convert that to pounds and see how much you paid for the parts attached to the frame. You probably can use the seatpost and the saddle, no need to buy new parts. The handlebars also are likely usable, even though newer 31.8 mm oversize bars (in the middle) are more durable.
Also, the 7-speed hub is probably narrower so you can't fit a modern hub unless you cold set the frame. Being made of steel, a professional bicycle mechanic can successfully cold set the frame to modern spacing.
I assume that your frame has 126 mm spacing. Modern road bikes use 130 mm and modern mountain bikes use 135 mm. Some touring bikes resembling more road bikes than mountain bikes use the 135 mm spacing instead.
The hub is probably a 7-speed freehub, so it only accepts 7-speed cassettes. If you cold set the frame, you can use a modern hub instead. A modern hub accepts 8-10 speed road and 8-11 speed MTB cassettes. Some modern hubs (but not all) even accept 11 speed road cassettes. It may be possible to transplant a 8-10 speed freehub body so your old 7-speed hub would accept 8-10 speed cassettes then.

Should I spend the extra on the upgrades?

I'd say if you are not used to downtube shifters, try to see if you still can find some indexed 7-speed bar-end shifters on eBay. They are not anymore being manufactured so that's why I proposed eBay (having lots of NOS and used stuff), but this could be the move to make the bike accessible with minimum investment.
In a pinch, you could even use 8-speed bar-end shifters. The cable pull for 7 speed (2.9 mm per shift) is close enough to 8 speed (2.8 mm per shift). If you adjust a 8 speed shifter to be perfect in the middle gear, it has at most 0.3 mm errors in the ends (about ten percent of the cable pull per shift which is insignificant). So in case you can't find 7-speed bar-end shifters, 8-speed shifters are usable very likely.
Note that adding bar-end shifters, you need to solve the cable stopping problem at the downtube somehow if changing from downtube shifters to bar-end shifters. If these are braze-on downtube shifters, Shimano makes downtube cable stops that attach to the shifter bosses.
A negative comment criticized bar-end shifters, saying that "Are you really going to be happier with bar end shifters? You’ll still have to move your hands for shifting (and just as far/deep, unless you are already on the drops). The great thing about brifters is that you can shift from the hoods and drops and even while braking.". So let me comment something about my background. I used to have an 8-speed hybrid bike with Shimano Rapidfire Plus "MTB" shifters which I converted to drop bar bike with bar-end shifters. I couldn't observe any issue with the bar-end shifters. Then I built a new bike (based on Surly Long Haul Trucker frame) and used 8-speed bar-end shifters which in my opinion are perfect. Only recently did I purchase a bike that has "modern" brifters. I consider the use of the same lever for shifting and braking non-intuitive, and I found I cannot easily click the small lever for upshifting in the rear with thick gloves on. So I consider bar-end shifters superior to brifters.


What to use to clean your chain (and cogs)? I've just tried cleaning my chain and cogs with some really hot water and washing-up liquid. I also used a toothbrush, j-cloth and a non-scratch scourer. After over an hour of some serious elbow grease I could shift some of the outer dirt and muck, but still can't get the base layer of grease off. What can I use to completely strip the grease and muck off the chain?

A degreaser, whether aerosol or not, is an excellent way to remove grease from the chain.

http://www.finishlineusa.com/products/citrus-cleaner.htm

http://www.finishlineusa.com/products/speed-clean.htm

The degreaser will reduce the amount of elbow grease required but be careful and use a set of nitrile gloves to protect your hands.

My simple chain cleaning method is as follows:

Shift into the big ring and little cog, wet the rag with the degreaser

Grip the chain (lower portion, going from big ring to the derailleur) with the rag, focusing on holding firmly onto the outer plates.

Turn the crank putting the chain through the rag. Readjust as necessary as you remove grease and grime from the chain (ie. don't keep rewiping schmutz back onto the chain).

When sufficiently clean, remove the rear wheel from the bike and place it between yourself and a wall (ie. tyre against your stomach/tyre against the wall keeping the wheel propped between yourself and the wall) over a garbage can.

Using a thin screwdriver or a cleaning tool ( http://www.parktool.com/products/detail.asp?cat=4&item=GSC-1 ) clean the grass and grease build up from between the cogs of the cassette/freewheel. Lightly apply degreaser to the brush portion of the tool and scrub at the cogs to free up the grease/grime.

Using a rag, with degreaser on it, insert the edge of the rag between the cogs and 'saw' back and forth with your hands thus spinning the cassette and fully wiping the whole cog. I typically move from top to bottom of the cassette (keep the grime flowing downwards).

Wipe down cassette, hub and any spokes/rim that could have been contaminated. Reinstall the wheel in the bike and one last time wipe down the chain with the degreaser rag.

And typically ... that method suffices for cleaning any of my bikes. The one caveat is that I typically don't let the chain get grease/grime covered and thus this takes about 3-5 minutes max and works really well. The worse your chain, the more you have to do.

You might want to look at your derailleur pulley wheels and using a flat edge against the pulleys as you spin the crank, remove the grease rings from the pulleys.

You might want to pre scrub the chain (similar to how you did the cassette) to loosen the grease/grime on the chain. A tooth brush w/ degreaser or the GSC-1 mentioned above would be sufficient.

Andddd... that's about all I've got for now. There are a plethora of other methods using chain cleaning tools, removal and soaking of the chain and nastier solvents but for the majority this method seems to work fairly well.

I use a lemon, natural and works very fine; easy to squezze and use it.
After I clean the chain I use no oil for the chain, I use a silicone spray or WD40 spray. The benefit is, that this stuff no have an contact with the dirt, only lubricate the chain.


How to add resistance to my bike trainer? I use a crossbike (http://www.konaworld.com/jake_the_snake.cfm) on a bike trainer (https://www.amazon.com/Kinetic-Road-Machine-Fluid-Trainer/dp/B01KHE5B4S) and have the chain on the largest front ring and the smallest one on the back, but the resistance felt too low. What I can do to increase the load?

This is the powercurve for the Cyclops 2 fluid trainer

You can see that at 30mph on the trainer you'll need to be producing around 400 watts. Using this website

http://www.machars.net/bikecalc.htm

46x11 will give you 30mph at 90 rpm (which is a reasonable rpm for home training). 400 watts is like a Pro climbing l'Alpe d'Huez. Note also that the power curve is exponential, every extra mph gets progressively harder. At 35mph you are in the 600-700 watt range.

Fluid trainers take a while to warm up - 5 to 15 minutes but generally offer more resistance while they do.

So I agree with the other posters, your unit is faulty in some way. If not, you should contact a Pro team for a contract.

Next time your at the supermarket go to the home goods section and get a pack of those felt pads for furniture legs. Cut 2 pieces the size of your brake pads, open your rear brakes and place one under each pad (sticky side toward the pad). If you have a normal set of brake levers you'll be able to adj. the braking or you can put something between you brake cable and frame and adjust it hat way also. Just having the felt in there is enough to cause to drop into a lower gear. You'll be able to adj. it so you can get up off the seat and crank hard. Simple. Your welcome.Peleton shmelaton.


How often should I change road bike tyres? My road bike has now done 500 miles, but unlike cars, I've no idea how often the tyres should be changed. It's used on normal road conditions. The brow of the tyre is now smooth.

How do I know if my tyres need to be changed, and how long should I expect tyres to last?

How long a tire lasts depends on a number of factors, including what type of tires you ride, how much you weigh, the conditions you ride in, front vs rear tire, etc.  In general, a good set of tires will last a couple thousand miles.

When the tire is totally worn out, you can usually see threads beneath the rubber in places.  Alternatively, the tire may start to bulge in spots.  In practice, road tires rarely get to this point.  Much more commonly, they start accumulating a lot of cuts from glass and other debris in the road.  When you start getting disproportionately many flats, it's a good idea to replace the tire (you can use the tire longer, but you'll probably waste more than a new tire's cost in tubes).

Got through 2 Continental Sport and three other tyres in about 4 years, which is about 20,000 km. Three had a hole in the sidewall, one had disintegrating rubber with viable threading, and one actually exploded!


What is a simple mnemonic for remembering the thread direction when removing pedals? Given that pedal threads are different on the left and right pedals: the right side pedal has a right-hand thread (removes counterclockwise, installs clockwise); the left side pedal has a left-hand thread (removes clockwise, installs counterclockwise), I often find myself trying to remember which way to turn the wrench to loosen a pedal.

Does anyone have a good-- preferably humorous and easy to remember-- mnemonic device to forever ingrain in my memory which pedal goes which way and keep me from over-tightening when I am trying to loosen?

What could be simpler than remembering that the left-hand pedal has left-hand thread?

I'm pretty sure that "righty tighty, lefty loosey" is the official answer, but I do like the "right is right, and left is wrong" one. Makes more sense to me. It's amazing how I can remember some pretty complicated sequences of stuff about all kinds of things, but this simple concept escapes me every time.


Keeping my ears warm while biking in the cold with a helmet Biking in the Northeast has become a challenge lately because of the cold; my ears freeze.

I can't wear a hat (because of my helmet) - I never actually tried, maybe I can.

Sometimes I'll put my hood on and then my helmet on top of that, it looks really weird. (Helmets look weird, hooded helmets are a whole new level of weird.)

I'm wondering if there are any other solutions.

I normally have a single Bluetooth earbud in one of my ears as well, not sure if that makes a difference.

Try searching for the term "ear band". They tend to be thin enough to comfortably wear under a helmet, and the good ones are fully wind-resistant, yet breathable.

If you have an open ventilation-style helmet, I recommend a helmet cover as well, which is a fabric sleeve that stretches over the top of the helmet which also significantly cuts wind passing through, and may be easier to use instead of a jacket hood (not to mention more streamlined). Install once per season.

Balaklavas or "dickies" are also good to protect the neck and shoulders, and there are also polar fleece neck warmers that may be more comfortable and can bunch up nicely under the back of the helmet.

Any quality of biking glasses/goggles are useful, too — look for ones with clear lenses — which will ensure your eyes don't get a full blast of cold directly.

You can use a buff under the helmet and a wind (rain) cover over the helmet. I bike with this outfit during the winter and it keeps my head warm even with wind an snowy weather below -10 degrees C.


Bike sharing services and systems What are some bike sharing services out there? I know that there have been some in Europe. Here's wikipedia's entry.

This is one that I heard of recently in NYC.
http://www.transalt.org/campaigns/bike/bikeshare?

I think that as cities make themselves more green, these will become part of the norm like rental cars or Zipcar.

Do you know of any new ones? Hear of anything starting in your city?
Anyone out there that is a member of bike sharing services? What worked and didn't work?
I'm really curious about what can make them successful.

My hope is that this post will generate honest and useful feedback so that companies offering these services or new companies can utilize the info here to improve on current offerings.

Also see: European cities have bike rental stations? on Travel.SE.

Barcelona
Barcelona has had a bike sharing program for about 3 years now, Bicing. Overall it's been a success with a huge amount of people signing up and using them every day.
Things that didn't work:

Bike stations weren't properly designed, it was easy to steal bikes. They have fixed this recently.
The lever to secure the seat was too small and people had trouble loosening it, they've now put huge levers on all bikes
The first bikes weren't at all reliable, for about 6 months I had trouble finding bikes that didn't have one or more of: tyres/brakes/seat/handlebar/chain/gears broken. I haven't used the service much in the last year because I got my own bike, but the times I have they have seemed more reliable.
Bike availability and parking spot availability. Stations that are on the top of hilly areas are always empty and stations near busy areas are always full. Solving this would require a lot more micromanagement of the bikes.
Instead of making an accessible web service for checking bike availability they decided to make an iPhone only app. This boggles my mind.

Other than that it's a great service when there aren't problems (I got charged 20 EUR when either the bike I had used got stolen or their system had a stroke and their records showed me having a bike for 8 hours, when I'd returned it after 26 minutes).
People have criticised using vans to micromanage the bikes, arguing that it offsets any ecological gains.
It initially cost 20 EUR/year, and is now 30 EUR/year. The pricing is:

First 30 min free.
Every 30 min after, and up to 2 hours total, 0.50 EUR.
After 2 hours, 3 EUR per hour until you return the bike. After this happens 3 times you get kicked off the service.
Steal a bike: 150 EUR.

In my bicycling history book, Bike Cult by David Perry, the author indicates that historically such schemes tend to fizzle out in a few years as the badly-maintained bikes remain unridden and the better ones get stolen or abandoned outside the area of the program.

We tried one briefly here at the university where I work, the "green bike" program.  It lasted a couple of months.

If it can be made to work I applaud; difficulties remain maintainance and repair, adjustment to individual riders, workable pickup and drop-off points...


What kind of jersey for summer heat and sun? With summer on its way, I'm looking for kit that I can wear in the summer to keep myself cool.  My typical routes don't have a lot of shade. What should I be looking for?  I know I am going to want a full-length zip, but what else?

Are there jerseys that are designed for this?
What about types and colors of fabric?
Is it better to wear long sleeves to keep the sun off, or short to allow sweating?

This is a matter of personal preference. I live in a hot climate. I've worn everything from sleeveless jerseys with perforated backs to long-sleeved jerseys in hot weather. My current preference is for long-sleeved jerseys, in order to get the added sun protection. There aren't a lot of lightweight long-sleeved jerseys, but there are some, and some advertise their SPF ratings.
Some clothing manufacturers advertise "coldblack" jerseys (black, but intended for hot weather). I've never tried one, and I'll admit I'm skeptical they'd be comfortable. I always wear lighter colors.
Jerseys are designed to wick sweat and breathe well. Modern performance textiles are pretty amazing.

I loved this durable cycling jersey. I rode my bike in hot weather. It was comfortable for me, of course, there is sweat, but the body is pleasant.
Material: Polyester. The fabric is lightweight and breathable. This T-shirt is made of synthetic fabric for effective moisture removal and air circulation. I have never experienced overheating while riding. This is very important for hot weather. In addition, a small price was important to me.


Fixed Gear crank arm slips The crank arm on my fixed gear "slips" when I put large pressure on the pedals like when I take that first pedal to get the bike moving or pulling up hard on my toe straps to slow down. The slip is very smooth and feels like if your back wheel was spinning in place on wet tile/marble, however, my back wheel is not moving in situations when my crank arm slips. I've just gotten the bike from shop maintenance a few days ago too so I don't think it's an obvious issue? I've heard maybe I need it's a cog or lockring issue. Can someone tell me more? I need to be able to pedal forwards and backwards with a lot of torque safely. Thank you!!

Your lock ring is loose.

Normally the cog is quite tight from pedaling and you can do some braking with it. When you brake harder it breaks loose and unscrews until it hits the lock ring. This is what you feel as sliding. The lock ring has left hand thread to keep the cog from unscrewing completely. Now that the cog has tightened against lock ring, the process repeats when you pedal hard forward.

Now that the lock ring rattles loose, you should tighten it immediately.

The crank arms have to be really tight when they are first installed. Properly installed they last indefinitely. However, if they get loose and you ride it for a while the crank arm will be ruined. You can't fix it. Just get another one. An old used one is fine. You need a crank puller to get the old one off. They are not that expensive.


To buy this damaged carbon bike or not? I'm looking to get an MTB and have been looking for this particular one for quite a while but stock is hard to get hold of.  I managed to find one in a store but the bike is damaged unfortuntely and the store is offering it with a discount of 10% because of that.  The damage doesn't bother me too much but I don't know much about carbon fibre bikes and it seems like it is pretty deep so wanted to understand if this will cause me long term issues, I'll probably have this bike for the next 10 years.
Should I buy it or is this kind of damage not worth it / going to cause me issues later on?

Close up:

I would not. You are paying for the frame. The SX Eagle RD has quite a few reports of failure, and it's bad quality overall. There's nothing special about the brakes (bog-standard entry-level), or the fork (Judy Silver TK, 30mm steel stanchions & basic Turnkey damper).
A carbon frame will provide more responsiveness on trails than alloy, but on-road this is no better - you'd be better off buying two bikes if, as per your previous questions, you'll be riding on road a lot as well. The weight saving here is nothing compared to the heavy tyres and upright position which will slow you down on asphalt.
And if you want a pure off-road machine then full-suspension alloy frame would be better.
If you are buying a bike with the advantage over alloy that it's 'more confidence-inspiring', then it doesn't make sense to buy one where you are concerned about frame damage before purchase.....
As far as this bike goes the frame seems to be the ONLY feature out of the ordinary, where the brakes are merely 'good enough', the fork 'entry-level', and the groupset 'cheap and nasty'.

I don't know much about carbon fibre bikes

Before buying a carbon bike, you should learn about the qualities of carbon fiber.
I honestly do not understand why people buy carbon fiber stuff. The warning about the special qualities of carbon fiber in nearly any bike manual should be a good reason to stay away from this dangerous technology.
Unlike a metal component that always cracks from the outside, by developing a visible crack, a carbon fiber component can just suddenly fail with no prior warning (well, unless you X-ray your bike weekly).
Unlike a metal component that can withstand impacts far beyond its fatigue limit, a carbon fiber component can dangerously weaken from a single crash impact. If you crash on a metal bike, you can always investigate the bike for bent parts and then keep a close eye on developing cracks for a certain number of miles, whereas the only advice I can give for carbon fiber components is "replace it if you don't know whether it's invisibly damaged".


What's difference between 1/2 and 9/16 inch pedals? I've this bike MTB hardtail Marin Bolinas Ridge 2012.

And it has generic composite pedals which I want to change.

So while choosing pedals I saw two different choices, 1/2 and 9/16 inch pedals.

I didn't understand what does this sizes mean and apply to what.

Please if someone can explain it to me.

For example: Diamondback Sound Pedal 9/16 and 1/2 model

The measurement is for the diameter of the pedal spindles, where they thread into the cranks. You need to find out whether your existing pedals' axle is 9/16" or 1/2". If there is no measurement indication on your existing pedals or the paperwork which came with your bike, ask your LBS if they could test out with some existing pedals to find out what size you need.

I had the same question. I know the basics of a bike (experience earned repairing my bike along the years)Today I need to replace pedals and when asking for the measure of 9/16 and 1/2 question, the answers are not clear: number of cranks (?) or sending you to ask to the bike shop (?).
A seller gave this information on the web:
Standards 9/16 inches (14 mm) and 1/2 inches (12.7 mm) Diameter spindles threat
So I took my bike pedal and measured: 12.7 !! so it must be 1/2 inch.
Solved.


Hydraulic Vs. Mechanical disc brakes What is the difference between hydraulic and mechanical disc brakes? Are hydraulics more reliable? Or more powerful? I'm curious since, hydraulics seem to get more attention and seem to be on professional bikes.

Hydraulics are used on higher end systems, cables are often a sign of a cheap brake set, so your observations are correct regarding "professional" bikes. However there are very good cable disc brakes (e.g. Avid BB7's) that are the exception that proves the rule. .

Cables have the disadvantage of friction that hydraulics virtually eliminate. It is significantly easier to modulate hydraulic brakes, you get more force delivered to the pads, hence more stopping power for the same input, and faster/more reliable and predictable pad retraction when releasing the brakes.
As the Hydraulic system is sealed, grit and grime cannot get in to jam up the moving bits, making them virtually maintenance free (replace worn pads is about all need doing)
Hydraulic systems are also easier to set up and adjust (with the right tools - next to impossible without them). Cables have to the exact length, and need "tweaking" as they stretch from new.

That said - a good quality and well maintained cable system will out perform a poor quality, cheap hydraulic brake set, so you cannot state "Its hydraulic therefore it's better".

Disadvantages of hydraulics occur when you get a leak such as hole in a hose or blown seal. They are less "field serviceable" than cables, essentially the brake is rendered useless and unrepairable (in the field) by a minor fault - which fortunately happens very rarely, and usually caused by poor transport rather than while out riding.

Another reported problem with hydraulics is boiling of fluid. This is more of a problem on road bikes where mountain descents of 100's of vertical meters in a very short time are more common. With overheated fluid initially the pressure in the system stops the fluid boiling. When the brake is released (even for a moment), the pressure comes off and fluid boils, and the brakes no longer work - at all - the lever just goes all the way in. Another thing that can happen is the rider stops with no problems, but the heat in the calliper (no longer being cooled by airflow) migrates to the fluid over the next few minutes, so when the rider rides off there are no brakes.  (This is different to disc fade where the pads and disc overheat and brakes loss effectiveness slowly - both types suffer this equally.)

Watch out in the future for Hydraulic shifters.... Available now if you have the big $$$$, lighter weight than XT and XX level components, almost certainly more reliable and easier to setup.... (Update 2015- Electric shifters mean these will not become main stream.)

there is a article take about this https://lightbike.shop/hydraulic-disc-brakes-vs-mechanical-disc-brakes

basically, the hydraulic is always better then Mechanical, but more expensive.


Are children's helmets with styling less safe? In a couple well received answers to a recent question it is suggested that sliding on the road is an important consideration for helmets.

A number of children's helmets now are available with spikes or ears or fins that would seem to have a meaningful impact of the ability to slide.

Are these helmets less safe?

Sad to say, I think with children the main injury mechanisms are falling off their bike at low speed or getting hit by a car. Both are blunt force trauma that the helmet can mitigate with little sliding.

Contrast against a road or mountain bike going downhill at 50 kph and wiping out at a corner.

just from personal experience from looking at childrens helmets I can tell you that a lot of childrens helmets with ears/spikes or fins have them mounted very high up on the helmet, often near or at the top. Which should not have a meaningful impact on the child's ability to slide as these protrusions from the helmet are likely to never make contact with the ground.


Carrera Crossfire 2 Hybrid Bike to a road bike I have a Carrera Crossfire 2 Hybrid Bike. I would like to convert this to a full road bike. Is it possible?, if so what changes will I need to make.

it is possible, but in most cases does not worth it.

Components cost more if sold separately, so usually you end up spending a same amount of money or even more than buying a new bike.

if any seller does discounts on bike - consider you have all the components discounted

planning and implementing conversion is not easy and time consuming

I have done such a conversion on a V-braked suspension fork bicycle. The bicycle had a rather short frame, making the conversion actually end up with a reasonable saddle-to-handlebar distance.
You need:

Drop handlebar + handlebar tape
Mechanical brake levers with same mechanical advantage as your current levers (for V-brakes, it means long pull; I don't sure what pull ratio your mechanical disk brakes use but I suspect it's the same as for V-brakes)
8-speed bar-end shifters -- you won't find these new but you can find new-old-stock (NOS) or used
New inner cables and cable housing for brakes and gears
Possibly: a shorter stem

I think such a conversion is a very good idea. The cables, levers and handlebar cost less than a full road bike. If you don't know whether you enjoy road bicycling with a drop handlebar, you'll find out, and you can always go back to your original handlebar. You also have a data point about the frame dimensions in case you decide to stay with drop handlebar bikes, and thus purchase a real road bike. The bar-end shifters are much better than those fragile combined-brake-lever-shifters you find on most road bikes today, unfortunately for buyers of road bikes and fortunately for drop handlebar converters.
Before the drop handlebar conversion, I suggest you to mount some real road tires (such as Continental Grand Prix 5000). Mounting such tires is easier than a drop handlebar and will give you one kilometer per hour of extra speed.
After the conversion, you need to see whether your saddle-to-handlebar distance is good or if you need to mount a shorter stem.


Super Heavyweight Biker keeps destroying Dutch bikes So I've had two Dutch style bikes and I keep breaking the spokes on them. The last time I had a custom wheel built using good components by a well known shop here (sapim and mavic components)... the spokes loosened after just one week. Even the shitty stock wheels I had on before lasted for longer.

I'm basically giving up on Dutch bikes and having other people built parts for me or repair my bikes. It just seems that I'm so far off the scale (literally) that no one has any experience with building working bikes for people my size (370 pounds).

From reading online it seems that the only working solutions have been 29er Mountain Bikes with freakishly large tires or cycles from this company in the US called Workman. I'm just wondering if there is not a middle way, I can't see myself using one of those riding the streets of London just yet. Even though the potholes here probably are comparable to offroad usage...

Any suggestions? One thing I have not yet tried is basically getting a full on Tandem hub and back wheel with 40 or maybe even 46 spokes.

I'd appreciate input from the few riders my size that I've seen on here.

My experience is with load bikes rather than people who are loads, but the principle is the same. A tandem rated wheel is your best bet, and possibly a heavier frame. Unfortunately most Dutch bikes are built for tall Dutch people who are generally not that heavy. 370 pounds is about 170kg, which is heavy. Pacific Island rugby player heavy.

What I would do is another custom wheel for your current bike, but with everything focussed on the weight. You can get hubs that are rated to a lot of weight, and Rohloff for example rate their hubs for tandem use even with only 32 spokes. But you should try for more spokes, I think, like the DT Swiss 540 Tandem with 36 or 40 spokes, or if your bike will take it the Halo Dozen with 12mm axle. Pair that with a heavy eyeletted rim like the Velocity Chukker or Mavic 719 and get it put together by someone who builds a lot of wheels.

Getting a custom wheel built with exact components can be mildly annoying, and not necessarily cheaper or better than finding a decent bike shop and letting them recommend something for you. That way you get their warranty. I suggest a load bike shop like Practical Cycles (found via google, I've never been there or to any part of the UK). If you do that and they get it wrong, it's on them to fix it. The magic words are

  fit for purpose  The goods should be fit for the purpose they are
  supplied for, as well as any specific purpose you made known to the
  retailer before you agreed to buy the goods.

(italics mine) Which incidentally means you should be able to get a complete refund for your current wheel if they can't fix it.

When we had this problem with a customer at the bike shop I worked at we first re-tensioned their existing wheel, but it broke more spokes the same day he got the bike back. Luckily he came back, because we were at least the third bike shop he'd been to, and even though I said "look, this probably won't work but I think it's worth trying" I wouldn't have been surprised to have him disappear. So we put together the heaviest duty rear wheel we could find, a downhill MTB hub we had in the shop with a 36 hole Chukker and somewhat oversize spokes (3mm straight gauge instead of butted just so it looked stronger). When I built it I took extra time to get it exactly right, and ran over it again after a test ride. He rang a few months later to say he hadn't had any more problems and just wanted to tell us.

(editing in some comments)

My feeling is that you can spend a lot of time and money trying to avoid just paying for something that will work.

The derailleur wheel is dished it's not as strong, as Rohloff discuss here and this Rohloff fan page might help :).

Use a 26" wheel in whatever frame you have as you will be using disk brakes so it's easy. A slightly smaller wheel is slightly stronger. Also, look closely at the rear wheel of this thing. That's a 9 speed 20"/406 wheel with 36 spokes that I threw together the night before I left on that ride. Normally it had four large panniers plus stuff on the rack, but a band is more interesting to look at. It was still going strong several years later when it was stolen. Smaller wheels make everything easier. If I could suggest a 406 wheel bike for you I would

Actually, the main problem that leads to broken spokes is not overall load, but uneven tension. I don't know the procedure that you or your LBS used to mount the spokes, but even small differences in spoke tension are a big problem.

If you have somewhat of a musical ear, you can easily check this: Just hit the individual spokes with a screwdriver and listen for the tone they make. If the different spokes are more than a quarter tone apart, that's your problem.

When I need to respoke a wheel, I've taken to just playing a sine note on my computer, and tuning my spokes to that tone. Takes a while because you also need to ensure that the rim ends up straight, but the result is surprisingly robust.


How to build surge brakes on bike trailer? There are a couple of pretty good answers in How to make a cargo trailer?.  After looking at those, at the answer to What are the safety concerns of a high vs a low mount trailer hitch? and doing some other research, it seems that heavy trailers have significant safety issues around braking.

All the references I found so far indicate solutions that involve disconnecting the bike's rear brake and connecting the cable to trailer brakes.  This solution has issues of its own (mainly around not going to the trouble).

There is common solution often used on rental automotive trailers, called a surge brake.

When the tow vehicle slows down, the trailer pushes against the vehicle and that force applies the trailer brakes. In automotive solutions this is done with hydraulics.

After thinking about this a while, and noticing there are many inexpensive used kids bikes with manually applied brakes integrated in the rear wheel.

Are there any proven approaches to using surge braking on bike trailers, either with used bike parts or with new purpose constructed parts?

The simple answer to your question is yes, people have built surge brakes and they do work. Specifically, I have built one, but I called it an inertia brake.

This page has some notes and photos. The mechanism was fairly simple and robust, a telescoping towing arm with a couple of standard brake cables leading to V brakes on the front wheels of the trailer.

The major caveat in my opinion is that by the time the trailer is heavy enough to need these brakes it's too heavy to be towed safely behind a two wheeled bicycle. I say 'two wheeled' because in many countries legally speaking a bicycle has "two or more wheels" - so to a lawyer my quad bike is a bicycle. I built that trailer for the quad and would not suggest towing it behind a two wheeler. Mostly because if you fall off the bicycle the trailer brakes will not be applied so the trailer will roll straight over the top of you.

You may also find "does anyone sell bicycle trailers with brakes?" useful

the guys from Carla cargo have released their solution as well (in German):

http://werkstatt-lastenrad.de/index.php?title=Bauanleitung_Carla_Cargo_Crowd#Nabenaufnahme_an_Gabel


Why is track cycling done counter-clockwise? As far as I have seen, track cycling is only done anti-clockwise/counter-clockwise/with only left turns, yet looking through what I can find (in a non exhaustive search) I cannot find any mention of this in the rules and regulations, is there a rule or regulations stating that track cycling must be anticlockwise or is it just convention? Or have I missed some clockwise track riding anywhere?

For clarification, by track cycling I am referring to riding round a velodrome

The UK National Cycling Centre FAQ (PDF) says:

Why do the riders go anti clockwise?
The Chariots in Roman times raced this way round, and athletic races and most other sports have followed in the same direction.

The Straight Dope says:

How do these things get started? I've gotten several letters asking why races are "always" counterclockwise, and I notice my fellow toiler, Omni magazine game czar Scot Morris, has written a lengthy treatise on the subject. Scot came up with the following list of counterclockwise phenomena: the Indianapolis 500 and other auto races, track and field events, Roller Derby, indoor bicycle races, horse races, speed skating, merry-go-rounds and other carnival rides, revolving doors, the chariot race in Ben-Hur, the customary flow of people around an ice-skating rink, the usual direction in which people spin Hula Hoops, the base runners in baseball, cable-operated model airplanes, and tornadoes and hurricanes in the Northern Hemisphere. ...
On the theory that there might be some dark link to our primeval past, Morris asked several distinguished anthropologists, but no luck. He morosely concludes, "the bias toward moving our whole bodies in counterclockwise cycles undoubtedly can be traced back to the right-handedness of our species and of every human society yet discovered, but how the one led to the other is unclear."

I didn't find it in the general UCI track rules, but it's in the track rules (PDF) of the UCI's World Cycling Centre in Aigle, Switzerland:

All riders must ride in an anticlockwise direction.

Right lane drivers when taking a round-about by bike or car on the road do it counter-clockwise. I guess it was more natural for them to define it like this.


What do the numbers on the mantle mean? I've just removed the mantle of my back tire as it has a hole (probably cut by glass). I wanted to look for a new one, but then I realized that I'm not even certain which size it is.

So I looked on the old mantle and found more numbers than I thought:

vtech EAGLE 42-622 700x42C <MDS> (Max durability System)

700 - 42 (42-622)

NL F024   17

I guess vtech EAGLE is the brand / model name, MDS is just some advertisment. But what do the numbers mean?

(Side question: Living in Germany and biking mainly / only in the city, where and for which mantle should I look?)

I think I just found the answer from https://commons.wikimedia.org/wiki/File:Reifengr%C3%B6%C3%9Fen-beim-Fahrrad.png:

So:

The diameter at the outer is 700mm,
it is 42mm wide at the outer,
622mm is the inner diameter


Loading front wheel in a sharp turn? When turning sharp at high speed, does it make sense to shift the weight to reduce risk of skidding?

I do not see the point of doing so. Both wheels are leaned at the same angle against the ground no matter how the weight is distributed. Whether the wheel starts to skid depends only on tire/road properties and on this angle, not on the force acting along. But a friend of mine, who is experienced more than me in cycling (and less than me in elementary physics) insists that it's better to "balance the weight" by loading the front wheel more.

Is there any argument for the latter statement, assuming identical front and rear tires?

He is right.

1) in cycling, weight is distributed more on the rear wheel (70 rear-30front approx.). So even assume that both wheel is at the same leaning angle, the front would lose traction first (friction proportional to reaction force). This is because the front wheel has less 'grip' limit than the rear wheel.

2) When rider starts to corner/or correct the cornering, the two wheel are not exactly leaning at the same angle. The front wheel both leans and steers the bike (see Figure). In simplified model, you can think that the front wheel is the only component of your bicycle that 'correct' the centrifugal force for the turn. In order to correct the cornering, the front wheel needs to 1) counter-steer, to balance the leaning, and then 2) change the steering appropriately. The whole process means front wheel lose grip more easily (rear wheel change direction less than the front).

You can see the video from Criggie's answer that the front wheel lost grip, just after he tried to correct the 'leaning' and the 'cornering radius'.

3) front wheel also has less contact patch (due to load distribution again). This can be verified when you are on normal cycling position, the rear tyre usually being 'flattened' a little more.

Video:

Partial momentum: momentum that is being shared between the Front and Rear wheel (from rider and bike itself)

Rider momentum: when cornering, the bicycle generally yawns at an angle to the 'original' momentum (in order to turn). That is why we need to lean, in order to balance the 'original' momentum that causes torque in rolling direction.

Lowering the center of gravity  by having weight on the outside pedal helps with stability, as well as sitting back over the rear wheel to increase breaking grip in the rear wheel. As such it is not wise to brake during the arc of the corner from my experience as you are more likely to lose traction.


How do I stop my clipless shoes and pedals from squeaking? I'm riding with Shimano SD66 sandals. They are awesome sandals and it's so comfortable riding without worrying about socks and shoes. I'm using Shimano pedals.

I'm getting a squeaking sound, mainly from one shoe/pedal at the top of the power stroke. I'm almost certain it's from the shoe/pedal because just adjusting the angle of my foot a little (inside the play allowed by the cleat/pedal) makes the noise stop.

I'm assuming that the shoe and pedal are deforming/conforming to each other and have started to rub at the most common positioning.

I'd normally look at lubricating, but don't want to use grease as that will track through my house and office.

Any other thoughts?

Rather than use grease, you can try using a 'dry' or wax based chain lube.

Apply the lube to the flat clips on each pedal - hit both sides if they are double sided mtb pedals.
If you think the squeak may be coming from the pedal itself, rather than the friction between the pedal and the clip, apply some lube to the spindle attachment points where the pedal rotates around the shaft.
Wipe away any excess.
Hold onto a wall or go for a ride and and clip in and out of the bicycle pedals until the lube is adequately distributed and worked in.
Repeat all steps if still squeaking.

If you carefully wipe off the excess from your shoes/cleats and the pedals, you won't be tracking anything around your house after your ride.

If after a second application the squeak remains it may be a problem with the bearings in the pedals - some can be overhauled, but others it makes more sense just to replace.

This is a common problem with SPD cleats. You may want to check the cleats for wear and mount them in the middle of the slots on the bottom of the shoes pointing exactly forward. Make sure the bolts are tight and give them another go. If the squeak has gone then try edging the cleats forwards/back to where you had them.

But why bother wasting time...

The other option is to get the Time ATAC pedal system. These are a much better pedal system because of how the cleat gets held and how the 'float' works. The pedals are also a bit more considerate if you catch your shins with them. The ch-mo ones are practically indestructible. An investment in them will be an expense you probably don't need right now but ten years down the line they will be amongst your most prized possessions and so pleased to have had ten years of use out of them. Google 'atac vs spd' and you will find that the only people that beg to differ are those that never tried Time. If there is a 'problem' with your pedal stroke then the ATAC cleats/pedals will be a lot more forgiving and easier on the knees.


Headwind when riding in a loop I (think) I know the answer to this, but I wanted to get others' takes on it.

Riding a loop with no wind, vs. riding the same loop with wind (such that half the loop, you get a headwind vs. tailwind for other half).

Does this equal out, or does the wind version use more energy/power to maintain the same overall time?

I actually don't mean keeping the same speed over the whole loop, but the same time around the whole thing. Thus I'd expect speed to drop while heading into the wind, and increase the other way.

If the effect of wind resistance was linear with respect to speed, then yes, the forces would balance out. That is to say: if pedaling into a 20 mph wind was only twice as hard as pedaling into a 10 mph wind, the forces would balance.

But this is not the case, as @Daniel mentions. The effort to overcome the 20mph wind is more than twice that needed for the 10mph wind. If we simplify your loop into an out-and-back (half directly into the wind, half with it at your back), say the wind is a constant 10 mph, and that you cycle to maintain 20mph, you can get an intuitive idea of how this works.

With those assumptions, for half your trip you would be fighting a 30mph headwind (10 wind + 20 from your own speed). The second half the "headwind" would be only 10mph (20 from your own speed - 10 from the wind). This is compared to a day with no wind, in which the whole trip would have a headwind of 20mph. The jump from 20mph to 30 requires much more energy (what is the last time you hit 30mph?) than the energy saved from dropping from 20 to 10mph.

Drag varies as the square of velocity. This means that velocity is the dominant factor in the equation (as opposed to drag coefficient).

From wikipedia:

  For high velocities (or more precisely, at high Reynolds number) drag will vary as the square of velocity. Thus, the resultant power needed to overcome this drag will vary as the cube of velocity. The standard equation for drag is one half the coefficient of drag multiplied by the fluid mass density, the cross sectional area of the specified item, and the square of the velocity.

For an excellent treatment of the forces affecting a cyclist, see Rainer Pivit's article. The graphs are especially helpful.

It doesn't equal out.

An illustrative hypothetical:

You have a top speed of 30mph.
The wind is blowing at >= 30mph.

Regardless of how fast you bike the tailwind half of the loop, it takes ∞ time to bike the headwind half, which is probably more time than in the no-wind case.


Should I drive or bike to work? I'm going to start a job next summer as a sailing instructor. I've volunteered before and biked the 3.6 mi (5.8 km) commute a few times a day on a mountain bike I found trashed a year prior.

I'm thinking because I'll have my license by next summer I won't need a new bike, but also this bike is just fine. The bike just has a bent wheel that is a bit wobbly and the gears are wonky. Would I be saving money by getting a bike and using that, or is it worth the space and luxury to just use the car? (I already have a car I would use).

I was thinking of getting something like this, but with fenders and a suspension fork: https://www.rei.com/product/816068/novara-randonee-bike-2014

I am located on the east coast of the US.

It seems like everybody has a false impression that I'm a sports instructor or that this is hard work; it's not. Sailing can be hard work, don't get me wrong. But I'm in a motorboat following the kids around.

Health

Two decades ago I threw away my bike.  Admittedly it was worn, but I had that "I have a car, why do I need a bike?" thought.

After a long time in a sedentary desk job, I got back on a bike and started the return to a healthy weight and muscle tone.

Best to keep the habit of healthy exercise by doing plenty of it. 3.6 miles (5 km) is 15 minutes at a casual pace, or 10 minutes if you're making an effort.

Nowadays my car does 150 miles (225 km) in one year, while I did twentyfold that on a bike.

you should bike because it helps you lose weight as well as gets you places without causing pollution! Let's change the world one person at a time.


How do people ride road bikes without fenders? I want to buy a bike. The road bikes look very gorgeous. However I noticed that they come without fenders to protect from water! I was really surprised for that actually and that made me wonder about how do people protect themselves when driving on wet roads.

When one drives on a wet road then you get smashed by water and your clothes get dirty. So how do people protect themselves when driving a road bike?! Are the tires somehow made that they prevent water? Or what is the secret?!

Most road bikes are the equivalent of an open-top racing car. You just don't ride them in the rain. And if you do, you are expected to be hard core enough that a little rain isn't worth the weight and aerodynamic drag that the fenders would cause. And there's also a reason that hardcore racers wear sunglasses during the day or transparent glasses in the evening -- they help keep bugs and rain out of your eyes. And as many people note, you'll be soaking wet from sweat anyway if you're riding hard.

That being said, there are some slim fenders that can attach to some road bikes -- although many/most road bikes currently being sold come without fender eyelets and are so aerodynamic that there isn't enough space between the wheel and forks/stays to put a fender that would work a darn. If you want fenders but like the road bike drop-bar style, look at expedition/touring bikes or cyclocross bikes.

Or, if you're like many people, you instead have a beater commuter with fenders that you ride in the rain and you keep your gorgeous carbon fiber racer for sunny days. One can never have too many bikes.

Not everyone will agree with this but here's goes...
Riding, for me, is a means to get out of the sanitized daily grind and thus rain, mud dirt are all welcome.
Fenders are ugly and if I can avoid them, I always choose to.


Relationship between speed and cadence? I am having a disagreement with a friend.  It stems around the scenario of 2 identical bikes on the same gear ratio side by side.  If the rate of pedaling is same for both do both bikes travel at the same speed?  Or does the rider's weight play a factor?

Speed is determined only by gearing, of which crank, cassette, wheel, and tire are components

Any 2 bikes using, say, 42t cranks with a rear 32t cog and 25c tires on 700c wheels at 90rpm will be going the same speed. Bike type and size, rider/bike weight, and even front wheel/tire size and crank length don’t matter. These other factors only effect how much power it will take to keep up that cadence with that gear combination.

Unless the weight was of significant delta, it would be near on impossible to see one bike travel faster or slower.

There are also too many other factors to consider:
Rider position
Rider height (longer legs, etc)
Rider muscle composition (stronger legs)
Cadence
Bike maintenance
Road surface
etc


What is the advantage of a reverse arch suspension fork? There are a couple of suspension fork manufacturers that have adopted a fork design where the lowers have a reversed arch.  I can't see that they claim any particular performance advantages for it, although there are some people on mountain biking forums saying they have improved torsional stiffness. Why would that be the case?

Also, how do they compare in muddy conditions, more/less resistance to clogging?

Looks like nobody has taken the geometry into account yet...

In the image below I have drawn the situation with highly exaggerated proportions.

All not-lowest-end suspension forks (at least the ones I know of) have a rake that is created by shifting the axle in front of the lower tubes. Let's take a wheel of radius r (solid blue circle) and add some clearance for the tire (dashed blue circle). Above that, the upper edge of the lower tubes shall be of equal height with respect to the upper tube's axis.

Here we can already see, that the wheel passes the front side of the lowers at a "higher" position than its back side. As the arches (green rectangles) have to span from one lower tube to the other over the clearance radius, we can see that the arch in the front side (the right one in the image) has to reach higher (higher green rectangle) above the lower tube's body than the one on the back side.

Technically speaking this means, that to build an arch with the same stiffness, less material (i.e. less weight) is needed on a reversed arch or at the same weight, the reversed arch can be built more massive and therefore stiffer. Unfortunately I don't have any measurement values about how much influence that really has. And obviously there are (or at least were, cf. heltonbike's answer) other drawbacks to be taken into account.

In my opinion it wouldn't give any advantage....except possibly with some lower end disc brakes where the rotas may tend to get very hot with hard use may make you slightly less prone to burned shins and ancles...other then that just a gimmic