Reoccurring Bent Axles, any reasons or upgrades? Earlier this month I had a issue with a broken axle.  It was the original that was sold with the bike and lasted around 5,000 miles.  I went to my LBS and bought a new axle (unbranded, labeled, etc, paid $13, came with cones, spacers, and hardware).  I did the install myself and had everything adjusted nicely.  The next time I rode it was on my commute to work, but I didn't get 4 miles into it when I found that I bent the axle.

I took the wheel to the shop but they wouldn't do anything about it since I didn't have them do the work.  However, I figured this was a fluke and asked them for a new axle and to true the wheel.  Once again I did the install of the axle and only got 15 miles out of it this time before bending it.  Before I got home I felt the wheel get stiff, but it stayed true.

The question is what will be a cause of bending 2 axles in 20 miles?

I think the guy at the shop said it was a cro-moly axle (while talking to another person today at the shop, these may not be), and he couldn't believe that I bent it.  If so, where would such an axle fall in the quality hierarchy?

Or is my hub toast?

While the wheel was being repaired, I swapped to a new original wheel for about 2 weeks.  I have not had any issues with it, but I wanted to keep it as new as possible.

Reading other questions I saw a comment that said not to use a hub where the bearing was catching.  I did have one in this wheel but I figured since it is a cheap wheel I would just burn it up and move on to a better one.  Besides, it has lasted 5k miles without issue to this point.

The bike in question is a 2008 Schwinn High Timber with Joytech freewheel hubs.  I do use a trailer with this bike using a Burley axle hitch.  While I had the hitch installed on both axles I bent, I did not have either trailer hooked up to them.

Something I would like to note is that when I removed the first bent axle (axle #2) that the cones on it had a wavy bearing track.  I didn't think too much of it, and I put them on axle #3.  Only having a few miles on them shouldn't have made a difference?

The reason for the bent axles is primarily due to your riding a bike with a freewheel. Freewheels (as opposed to a freehub) have a length of unsupported axle on the drive side of the bike that is vulnerable to bending. That is the primary reason why freehubs were invented. As the bike industry moved more and more gear sprockets (6, 7, 8) this meant a wider cog and longer unsupported length of axle. It is amazing how many cheap modern bikes (Schwinn sold out their name for use on low quality bikes long long ago) are still using freewheels which are an obsolete technology at this point. http://sheldonbrown.com/freewheels.html

Improperly adjusted or worn bearings are not considered a major factor in having a bent axle unless the bearings are very destroyed and the wheel is not working normally. Bent axles are due to load. So, you using a heavy trailer and being a larger than average rider, the axle is more likely to bend.

Get a strong well build wheel with a freehub. If you want an axle of CrMo then make sure you are getting it. There are OK inexpensive wheels for $40 so at $15 per axle replacement (excluding labour) it really makes more sense to not be replacing axles. Joytech is a cheap hub. Buy a good quality wheel that is worth >~$100 and you will save time and money in the long run.

I'm curious what you mean by "bearing was catching...just burn it up" That sounds like you may not be adjusting things properly. Maybe review some insructions on doing a hub overhaul or go down to your local recycle a bike shop for some hands on learning?

I'm also curious how you could tell specifically by the mile when your axle bent? Normally a bent axle is hard to notice unless the wheel is removed.

I find that rear wheel axles even of freehubs can be hard to keep straight. My old parallax hub with an 8spd freehub would always have a slight bend when I took it off to examine it and this resulted in uneven bearing wear. Probably due to me carrying very heavy trailer loads, passengers etc. North American bikes are often designed for sport rather than long term utility so even a tall person may be outside of the design for the bike. My solution was to get an old new XTR titanium axle that was laying around in a parts bin at a shop I did business with. Since then my rear wheel hub has stayed well adjusted :-)

I have a Giant MTB ATX with 21 speed setup and QR skewers.  To date I have broken one 9mm diameter rear axle in two pieces and and bent three others, in 12 months.  The last one was just three days ago.
I have ridden and raced bikes since I was 13 years old and I still have my old Condor road bike and Condor Track bike, both of these are 50 years old and still on the same hubs, wheel and frames.
I rode 400 miles a week when I was young and raced most weekends, took part in the compulsory crashes and the bikes are scratched but very usable.
Answer: these failures are caused by poor-quality Chinese steels, under sized and over produced.  The bike industry is lucky that to date no one has been killed by these failures. The industry seems now to go with 10mm and 12mm or bigger axles must reflect on this issue.


What to do when a car turns into a side road (etiquette)? If a car is turning right onto a side road and not an intersection, what must I do?

Perhaps I am 25 feet/7.5 meters (and another cyclist just passed the car that's turning right), should I

A) Try to speed up to clear the car?

B) Slow down to let the car pass?

I live in Ontario, Canada, and am also driving with traffic. Evidently the first choice is more risky. What if cyclists are behind me; what if there aren't?

As you're in Ontario the following references are official.

Look at the picture at the bottom right of Toronto's Understanding Bicycle Lanes -- here's an excerpt:

In summary, stop behind or pass to the left of the turning car.

I generally expect drivers to see what's happening out the front of the cars, but never expect them to know what's happening to the side of their cars.

In the illustration above, for example, I guess the driver is looking forward (at the intersection which they're turning into), not looking sideways (at the space between them and the sidewalk where it says "No").

Ditto at stop signs and stop lights, by the way. Especially if it's a truck, beware of pulling up close to the intersection squeezed between the truck and the sidewalk: because if the truck turns right without seeing you're there you'll be squeezed between the truck and the street furniture; so hang back in the bike lane away from the intersection (give them space to turn if they're going to), or even temporarily take the lane (occupy the car lane) behind them until traffic starts moving again.

See also this page, Car Bike Collisions | Motorist Right Turn, which says,

  Motorist turning right collides with cyclist travelling in parallel direction

  Key problems:

  motorist overtakes cyclist just before turning right
  cyclist tries to pass to the right of right-turning motorist
  cyclist riding on the sidewalk fails to stop and yield to turning vehicles at intersection

  To avoid:

  look ahead for turn signals
  watch out for drivers slowing down in preparation for a right turn
  stay away from the driver's "blind spot" (near the right rear wheel)
  do not pass right-turning drivers on the right
  use the road, not the sidewalk, to be more noticeable to motorists

What if cyclists are behind me; what if there aren't?

On a ski slope it's the job of people up-hill to stay out of the way of people down-hill. I reckon the rule's similar for cycling in traffic, not to mention driving, i.e. do what you need to and count on cyclists behind you (if there are any) to not run into you (I don't know, maybe that depends on where you are and how fast you're going).

But use hand signals when you change lane, and ideally also when you slow i.e. when you're about the brake, that's what you can do for them.

Continue to ride predictably - so keep your pace and continue straight (unless you are turning right as well on to that side road, in which you should signal as such, and execute your right turn).

Your question has much more to do with what the driver will do than you - therefore if you continue on your course, you are riding predictably, and they can execute the best way to turn, as they are faster and more dangerous roadway user. This also applies to those cyclists or other roadway users behind you.


Turning right but can't see cars coming (UK) I'm a newbie to cycling and I was wondering if I done the right thing or I should do something different next time.
I'm coming down towards a main road where I can either go left or right. I want to go right. Both sides are packed with parked cars. I can see there's no cars coming to the left of me but can't see to the right of me. I couldn't hear a car coming up either. I look left and decide to slowly roll out while standing up on pedals. As I'm rolling out I'm looking right and then see a car coming at me (electric taxi). Not really close but still I thought I better get across quickly just to avoid any incident, so I pedal across and feel car come quickly past me.
I should normally hear cars but I didn't this time. I didn't really enjoy not 100% knowing a car was coming up the road and having to quickly pedal across. Did I do the right thing by slowly rolling/edging out?
Sorry for newbie question just wondering if I should have maybe got off bike and looked on foot or something.

It's not easy.  A few factors make it harder.

The double yellow lines don't extend vary far up Chipperfield Road (for those not in the UK, they mean "no parking").
Cars can come up too quickly for the conditions, and taxi drivers are notoriously impatient, as well as likely to pass too close without slowing down.  Seeing a hazard rolling out of the junction the driver should have slowed and prepared to stop even if you were being stupid (which you weren't).
Electric cars at urban speeds can be very quiet, easily drowned out by general traffic noise from further away.  Like you I use my ears a lot when riding.
In the dark, modern streetlights remove a cue I used to use - the reflection of white headlights on the road lit by orange lights was the first sign of cars at one junction I ride regularly.

That said there are a few things you can do.

First you need to be aware of your lines of sight, and when they will open up.  So as you roll forwards, you need to be looking right when you can see past the parked cars.  And not just past but through and over them.
Look for vehicles coming from the left further away.  If the road is only wide enough for one car, have they stopped to let someone through?
You may need to stop suddenly, put your feet down, and take a step back.
Eventually though, you may be committed to going - do so decisively.  Pedalling hard for a couple of seconds doesn't just accelerate you, it signals that you're definitely moving.

Standing up on the pedals raises your head (only a little because you've got to hold the bars), helping you see and maybe even be seen, but you'll probably roll a little further before you can put your foot down.  I'd stay seated, unclipped from the pedals, but I'm tall and choose pedals that I can clip to but can ride gently without clipping in.
The problem with getting off is that by the time you get back on things have changed.  The only thing to do then is cross on foot and rejoin.  That shouldn't be necessary here, but it's always a valid option

No. Very clearly if you “feel” the car come past you, you’ve taken far too much of a risk.
What to do about a car “not really close” is purely a value judgement, to be made only at the time and only by the rider on the spot, though it will clearly be made harder by standing up on pedals… That would mean you were cruising, balance dependent entirely on speed.
If there’s any doubt at all, you don’t try to get across; not “quickly” nor any other way. If there’s any doubt at all, you hold back.
Only when you’re sure there’s time, should you even think about risking it.
Who doubts that please explain how much damage the crumpling bike or the dying rider is likely to inflict on the car, however close it seemed before the risk was taken?


Repair frame with crack by seatpost clamp Is it feasible to repair a crack in a frame around the seatpost clamp? Being an aluminium frame I understand soldering is problematic. It doesn't matter if seatpost is fixed in place as per a solution involving epoxy/some kind of wrap etc.

Is it feasible to repair a crack in a frame around the seatpost clamp?

feasible:
1. possible to do easily or conveniently.
2. likely; probable.

It is possible to repair an aluminum frame. It is not easy or convenient.

It's all about how much effort/money you are willing to put into this project.

Finding someone with a gas tungsten arc welding rig who would be willing to weld on your frame is one thing. Finding someone who knows what they are doing is something else.

Here is a discussion on a welding forum with an intelligent answer on aluminum bicycle frame repair. Here is a snippet of the conversation relating to repairing a frame:

  Any repair should be made via gtaw (tig-heliarc) by an EXPERIENCED welder.  If the frame is truely 7005 then 5180 would be the filler material of choice.  This will allow the frame to undergo heat treatment to restore it to its original condition.    If the frame is actually a t6 alloy more than likely you should use a 4643 filler which again will allow heat treatment.....if you wish to repair without heat treatment use 5356 which will work on either alloy but without heat treatment it will never be in the condition it was when produced.

The most feasible solution is to see this as an excellent opportunity to upgrade.

It IS possible to repair this.  It is possible to repair practically EVERYTHING that is man-made.  Although it is impossible to say how cost-effective or how easy it will be by just looking at a couple of pictures, I would be confident that this frame could be repaired well and fairly cheaply.  Yes, I'm one of those that hate the throw-away society we've become.


Why do cyclists prefer messenger bags over backpacks? Ok, I know form sometimes follows function - and things can be even more funnily irrational when fashion and trends come into play - but what's the lure of the cyclist's messenger bag?  I see them everywhere, and can't help but imagine them to be a big pain in the lopsided way they hang on a single shoulder, not to mention the strap-over-the-head maneauver required to take one off, becoming even more awkward in tight quarters like say a small cafe.  But there they are, ever popular.

People who enjoy using them tend to be quite passionate about them - and I doubt it's limited to just the style of the bag. Having little experience riding with backpacks or messenger bags, I ask, why do you choose to ride with one over the other?

I spent the last two years as a backcountry ranger, in Northern California.  There, I wore a backpack almost every day.  Now I am a bicycle commuter in Sacramento and I choose panniers first, a messenger bag second, and the backpack a distant third.

There are three reasons why the backpack is my last choice in this list.

Any bag I carry ends up being full.  I don't know how that works, but my bag is always full of something.  A full backpack rides higher on my back than a messenger bag.  This raises my center of gravity and throws me off balance more easily.
It doesn't matter how gently I ride or what the temperature is, by the time I get to work I am soaked with sweat.  With a backpack, I sweat even more because there is less airflow between my back and the bag.  The messenger bag, which rides lower, covers less of my back and I sweat a little less.  Or maybe I just dry out quicker.
Backpacks with hipbelts and sternum straps are designed to move weight off of one's shoulders and onto the hips and torso.  This works great if you are in an upright, walking position.  When I'm in the drops on my roadbike, a hipbelt is nothing more than a hinderance and a backpack-sternum-strap, though more useful, sometimes tends to choke me.  Weight is again transferred to my shoulders and back, which causes me some degree of pain after a while.  Messenger bags--at least those that are well designed--have a strap which rides diagonnally across the sternum and which functions better in the riding position to transfer weight to the torso.

Panniers are my first choice, though, because they better solve all of these problems.  They are completely off of my back and pretty low on the bike.  For longer rides and for my daily commute, I generally use panniers.

Not all of my bikes have a rack, though.  I have ridden my bike from Sacramento-to-the Bay Area wearing a messenger bag.  I wouldn't have tried it with a backpack.

When I did commute I would use a Kelty backpack. I was never concerned with the sweaty back thing because I was lucky enough to have showers and a locker at work. If I needed to stay clean the sweaty back would be a real concern of mine and then I would opt for panniers.

The messenger bag thing is such a fad. Don't buy into it. It is not functional like a backpack or panniers. The people who use them want people to see them. It's a fashion statement on par with skinny jeans and thin mustaches.


Did I purchase the correct brakes for my Huffy bike? Did I purchase the correct bike brakes for my Huffy bicycle.  I just put the back set on the back and no matter how hard I squeeze the brake it is not tight enough to stop bike.

If anyone know please help thanks.

Firstly you need to confirm the material of your wheel. If your wheels are carbon fiber, you need to use the professional brake pads made of cork which are normally labelled as "use for carbon rims".

If your wheels are aluiminium/alloy or steel, use pads made of rubber.

Secondly you need to confirm the brake type of your wheels. The mountings for V brake pads and caliper brake pads are different.

Your photo shows pads for an older bike with caliper brakes.

Please take a picture of your brake and add it to the question.


What use does a Heart Rate Monitor have if you have a Powermeter? When should you be riding by HR instead of Power and what can you learn from a HRM when you're riding by Power?

You can tell when you are knackered.

Power indicates your actual output.  With a baseline of previous power and HR data, you can establish a model for what you should be able to do.  When your numbers start to fall way outside your model/baseline (you normally produce 250W at 80% of your max heartrate, but now you are only producing 200W at 85% or 90% of your max heart rate) it might be time to do something about it (check hydration, calories or just end training for the day).  Additionally in off training times your resting heart rate can be looked at as an indicator for how well recovered you are.

Power output is a finite number that is extremely useful because comparisons can be made directly across riders.  However, your own stats bio metrics are more useful to you as an individual because they can help guide your training and prevent you from overtraining, help show your individual improvement, and let you know when you are recovered and can accept an increased training load.

I use an HRM with my PM when training indoors to monitor my cooling and hydration strategy.


Steel vs. Aluminum Wheels I was at my local bike dump looking for a spare set of wheels for an older bike I have.  He said that they have lots of steel wheels but very few aluminum.  Whats the deal on this?

What are the differences between steel and aluminum wheels?  Why are aluminum wheels more desirable?

Steel makes for a heavier rim; the modern-box section design works well for taking advantage of aluminum's lower density.  Furthermore, since steel will rust, the rims are typically chrome-plated.  The chrome plating makes rim brakes almost useless in the wet, which is exacerbated by the poor pads used on most of the classic bikes that shipped with steel wheels. In contrast, steel rims are almost indestructible - they can be bent out of shape and re-bent repeatedly and will wear much longer than aluminum rims.

As far as your specific case, many older bike-boom era bicycles were built with "Schwinn"-sized wheels, ISO 590 or ISO 597, both labeled as 26 x 1 3/8".  As far as I know no manufacturer makes aluminum rims in that size, so finding a replacement wheel for an older bike usually means either getting new brakes and converting it to a modern size (ISO 559 or ISO 584) or finding an old wheel that's not too beat up.  The latter is usually pretty easy, cheap bikes ship with steel wheels that are often simply discarded.

If you plan to keep your bicycle "stock", choose appropriate rims and tyres regardless of their material.  Steel rims make sense if your bike is a vintage one or a cruiser.

The main aluminium advantage is a lesser weight but you must you pay for lesser weight due to cost of aluminium.

Also a marketing is present here: a man who buys cheap bike is also expected as a man who will search for a cheap parts to repair this bike. So steel rims are what this man will search for.

UPD (from my comment below):

regarding original question: the main aluminium advantage is a lesser weight but you must you pay for lesser weight due to cost of aluminium. Also a marketing is present here: a man who buys cheap bike also expected as a man who will search for a cheap parts to repair this bike. So steel rims are what this man will search for.


Patched up my tire and still lost air again I recently popped my tube and I took it out and put a patch on it and made sure that there were no other holes and I didn't find any so I filled it up and rode on it for about an hour, then the next day it was flat. Can you guys please help me!?

And I also patched up the hole in the tire so if anyone can help me that would great.

As well as checking for debris in the tyres, applying the patch properly etc., you need to be careful not to give yourself a "pinch flat" when you put the tyre back on the rim. This is caused when you trap the tube between the tyre and the rim, putting a fresh hole in your recently repaired tube.

Using the scraping tool or sandpaper to abrade the patch area may also leave the tube thinner. When inflated the thinner area stretches and may allow air to leak. You might have to stick the (temporarily) inflated tube under water to find these tiny leaks. Scrape sparingly, and the tube may still have plenty of life left. I am still riding a tube with six patches spread around on it.

Also, using a CO2 inflator always seems to leave the tube flat about a day later. If you use one of those to inflate a tube on the road, expect to re-inflate later with a proper pump.


Advantages of mounting bottle under frame I'm wondering if there are any advantages to mounting ones water-bottle on the bottom of the down tube, near the ground, versus on top of the tube.

I'm mainly interested in the advantages, or lack thereof, in the context of a road riding.

It seems like if you are riding a mountain bike or riding off-road, it could protect your frame from stumps, branches, or anything else that you could land on that is taller than the bottom of your down tube.  Also, I could see it helping to keep the center of gravity of the bike as low as possible, for mountain and road.

Are there any other advantages to mounting a bottle on the bottom of the down tube on a road bike?

Other?  I would not count protection as the first.  The cage is a lever and some edges.  A water bottle is not exactly an impact attenuator.  And you have the chain ring to get past.

You pretty much only see a third on touring bikes. It is the least convenient location but it is a third location.  Three bottles or a frame bag and one bottle.  Pretty much impossible to access while riding.  Typically don't have the clearance in the  bottom position for a long bottle.

Someone commented on pull downwards.  Notice I used solid loop cage below.

I give center of gravity zero points.

On a mountain due to a small triangle it is typically the second cage so naturally it is going to be more common on mountain.  Still the least functional position. On a mountain bike you can shake out a water bottle. I tried it on my mountain and gave up.

My best use of the last position is margaritas on Critical Mass. You give up volume to insulated containers. That is a large frame and that is 70lb dog.

I've just come across a pic showing an excellent use of the under-belly bottle cage.

OK its not actually underneath the frame, but that is an air pressure vessel which powers an air-horn like the Air Zound http://www.airzound.co.uk/

You only need to access the air tank to refill it when stopped, else it can just hang there out of the way but still near the front of the bike.

No real Centre of Mass advantage because a bottle of air is not heavy.


Which way do I orient my bike tire's tread direction? and why? I have a mountain bike tire that has stamped on the side something like:

<----------front   rear------------->

Which seems like a pretty clear indication that the tire should be oriented in one direction when used in the front, and the opposite when used in the rear.  Is that right?  This is counter intuitive to me - I would have expected tire tread to face the same direction on both wheels - like cars.

If so, is this true in all cases?  For example, road bike tires with tread to handle rain?

And finally...why?

The tires have more traction in some directions than in others.

Your front wheel does most of the braking; your rear wheel does all of the propulsion.

Tires are oriented to give the most traction to the primary fore-and-aft forces.

Not sure this is even still an issue for the original poster, but I didn't see the answer I would have given to his actual question: ["I have a mountain bike tire that has stamped on the side something like: <----------front rear-------------> Which seems like a pretty clear indication that the tire should be oriented in one direction when used in the front, and the opposite when used in the rear. Is that right?"]

No, the tire stamp is pointing in the direction of the front/rear of the bike. Almost assuredly the stamp is actually <---- Rear/Front ------> (rather than Front/Rear) since the industry standard is to stamp this on the right side of the tire. This will put the stamp and colored logos on the same side as the sprocket (not sure if that means anything but that is how I was taught). This is how the manufacturer felt their tire would best be used with air flow and grip, but you can flip it either way depending on your purpose. (I use the logo/direction arrows to mark the tire at the air valve so that when I find a hole in my tube, I can find the thorn easier in the tire as well)

On a side note, if there are 2 direction arrows on the same tire, one says something like "Direction Front" and the other says "Direction Rear" then you would flip the tire depending on if you are using it on the front or rear wheel.


Where should I prefer and avoid cartridge bearings in a bicycle? All bicycle bearings, hubs, bottom bracket and headsets used to be cup and cone
bearings. However, recently there has been a trend to replace these with
cartridge bearings in new parts.
Is this a good path?
What benefits and drawbacks do cartridge bearings have? Where should they be
preferred and where should they be avoided in a bicycle?

I'll keep this answer short and simple.
Cartridge bearings from reputable manufacturers such as NTN, NSK and FAG will outlast their loose ball bearing counterparts assuming no maintenance is done.
90% of the issue arises when people do not use cartridge bearings from reputable manufacturers. As such, the argument that cartridge bearings are "unreliable" compared to their loose ball counterparts arises.

First, let's take a look at different types of cartridge bearings. There are
angular contact bearings that require an axial preload and can handle both
radial and axial loads, and deep groove radial bearings that are best at
handling radial loads but can handle usually axial loads as well. Headsets use
angular contact bearings, whereas hubs and bottom brackets have to use deep
groove radial bearings.
The angular contact bearings are nearly always full complement (are fully
filled with balls) because it is easy to snap together their races. However,
deep groove radial bearings are hard to make full complement. The reason is
that the parts have an overlap and thus easy filling is made by half-filling
them with balls (half complement) in one side, putting the center race in,
redistributing the balls evenly, and adding a retainer to prevent the balls
from ever going to the same side in use. This method is known as offset filling
and was invented by Robert Conrad.
There are slot filled full complement bearings too but they are poor at
handling axial loads and thus won't last long in a bicycle hub for example.
Bottom brackets: cartridge bearings are acceptable
Historically, bottom brackets had a square taper spindle with cup and cone
bearings. The too-small axle was prone to failures but the
eleven 1/4" balls on both sides
were big and numerous enough. However, a drawback of cup and cone bearings
as used in bottom brackets is that the bearings are "backward" unlike
what they are in a hub for example, so the design increases bearing loads
(details).
Then to simplify changing the entire assembly, square taper cartridge bottom
brackets proliferated. They share the too-small axle of the cup and cone square
taper bottom brackets, but despite the "cartridge" name at least the Shimano
offerings still use cup and cone bearings
(source: twelve
7/32" bearings on one side and eighteen 5/32" bearings on another side).
To solve spindle failures, Octalink was offered with bigger spindle.
Unfortunately, the faulty design lacking press fit leads to left crank
arm loosening and the big spindle leaves little space for bearings.
Apparently Shimano uses cup and cone bearings with eighteen 1/8" balls
on both sides (source).
Finally a solution was found to bottom bracket problems with Hollowtech
II that moves bearings outboard so that both the bearings and the
spindle can be big. It is an implementation detail that Hollowtech II
uses cartridge bearings but the bearings are large (37x25x7 mm,
source) so
even being half complement is not a disaster, and the most of the cost
of a Hollowtech II bottom bracket is the bearings so changing the
entire threaded parts is not a problem.
Thus, because the only satisfactory bottom bracket is Hollowtech II, because
all cup and cone bottom brackets have the bearings "backward" increasing their
loads, and because Hollowtech II can use big bearings, it is not a problem to
use industrial cartridge bearings instead of cup-and-cone bearings in bottom
brackets, except perhaps in press fit frames where bottom bracket swap requires
expensive tools (such frames are best ignored as they are a disservice to
cyclists).
Headset: cartridge preferable
Early bicycle headsets used cup and cone bearings and they failed with a
failure mode called "indexed steering" where the steering develops a notch in
the straight position so that it takes a bit of force to turn the steering away
from this position. Later, the cause was found to be
vibrations the bearings can't absorb,
and by adding a conical or spherical interface at both contact points of the
bearing solved the issue. This naturally leads to using angular contact
full complement cartridge bearings. Because the bearings are angular contact,
they can be very easily made full complement so the bearings don't suffer
from the typical problem of cartridge bearings that only half complement is
possible.
When compared to for example cartridge bearing hubs where changing bearings
requires an expensive tool, these angular contact bearings are very simple to
change. In fact simpler than changing cup and cone bearings where the cups
required a press fit tool to change.
Because cartridge bearings solved a genuine problem in early cup and cone
headsets, and because cartridge bearings are simpler to change than cup and
cone bearings, in the headset application, cartridge bearings are preferable.
Hubs: cartridge should be avoided
Traditionally, hubs used 3/16" cup and cone bearings in the front and 1/4" cup
and cone bearings in the rear. However, recently, a problem in the quick
release system was found by the adoption of disc brakes: the front quick
release skewer self-loosens gradually on disc brake bicycles, eventually
causing the front fork to jump out of the front wheel during hard braking. As
this is dangerous, manufacturers switched from quick release system to thru
axles on disc brake bicycles. Unfortunately, the desire to use 11-tooth
sprockets in the rear hub mandates a maximum diameter for the bearings, and the
thru axle made the hub axle larger, so not much space is left for the bearings
and thus 5/32" balls are used in today's thru axle cup and cone hubs. Only time
will tell whether they are durable.
A cartridge bearing hub has the same restrictions that a cup and cone hub has in
that the bearings must fit into a confined space, but has many additional
drawbacks: no bearing service is possible without an expensive bearing press,
and the bearing has reduced lifetime due to needing to use the same size balls
that a cup and cone bearing would use
(due to needing to fit to the same confined space), but with no possibility of
having a full complement of balls and needing to have half complement due to
the offset filling used to manufacture the cartridge bearings. Typical
cartridge bearings used in hubs are 28x15x7 mm which is arguably too small
especially as a half complement bearing when compared to e.g. the 37x25x7 mm
used in bottom brackets. The 28mm outside diameter cannot be made larger due to
fixed freehub body dimensions and the 15mm inside diameter cannot be made
smaller due to fixed axle dimensions.
(In theory, it is possible to make a hub
that uses different bearing size between the hub shell and the axle than it
uses between the freehub body and the axle, but that's not much help with today's
ridiculously small chainrings typical of MTBs -- for example a 20 tooth chainring
has 40 millimeter radius as opposed to the 170 millimeter length typical of
cranks, multiplying the weight of the cyclist by a factor of 4.25x so in fact
the freehub body bearings are the most important bearings in a hub due to huge
chain loads.)
It is very important in a hub that bearing service is simple, because unlike in
a bottom bracket, changing the entire hub is not feasible because it takes many
hours to re-spoke the wheel for a new hub. In fact, changing a hub is probably
the second most difficult component in a bicycle to change (with the most
difficult being the frame) so it is of utmost importance that most hub bearings
service can happen without special tools. Cup and cone bearings allow
regreasing after water intrusion without expensive tools, and the balls and
cones can be changed without expensive tools. The rarest failure, cup failure,
requires a press fit tool but that's the only case where a cup and cone hub
requires non-standard tools.
Thus, hubs should ideally use cup-and-cone bearings. The only reason one cannot
find expensive "boutique" hubs with cup-and-cone bearings is that nearly everyone
who can fool unsuspecting cyclists to buy a custom "boutique" hub at a great
price can set up a CNC machining shop to manufacture hub shells and then put in
industrial cartridge bearings bought from bearing manufacturers, but having
capacity to manufacture cup-and-cone bearings is only possible for major
players like Shimano.


Can I use WD-40 on my bike? Is WD-40 really bad to apply on bikes? I was told so but still see people doing that.

Also I saw WD-40 launching their new products of bike lubricant and degreaser. Did anybody try those?

WD-40 is mostly a solvent with a very light lubricant mixed in. It's great for getting stuck parts moving again. When you spray it on, the solvent dislodges whatever gunk may be causing the part to stick and then evaporates, leaving a light lubricant behind. This will allow the previously stuck part to move again.

The reason it is generally not considered a good bicycle lubricant is because it is a light lubricant. It's just fine for household items like door hinges, which aren't exposed to weather and don't get moved a couple hundred times a minute. But the lubricant is not thick enough to adhere to rapidly moving bike parts for any length of time, especially when you add a little bit of road grit and/or rain.

Some people do use it for loosening up shifters in the winter time (they stick when it's cold) or cleaning chains and derailleurs. You will notice in the answers and comments on the aforelinked question, and this one, that whether or not this is good practice is highly debatable. Some people will use WD-40 as a cleaner and degreaser followed by a bicycle-specific lubricant, with or without a cleaning inbetween, depending on personal preferences.

I don't have any experience with their bicycle-specific products, but they're a solid company that's been in the business of cleaning and lubricating mechanical parts for a long time. They also make Lava soap and 3-in-1 Oil, a product that was originally designed as a bicycle lubricant (although they did acquire both of those from other companies). I actually didn't know until I read this question that they were making bicycle-specific lubricants now. Given their history and the number of patents that they have to draw ideas and develop from, I'm certainly willing to give them a shot. The worst case scenario is that I have to clean it off and go back to my previous products.

I like wd40. I usually use this protocol when using it for both degreasing and lubrication.  This only works if wd 40 is being used for both degreasing and lubrication, and there cannot be substitution.

1) Spray chain and cassette and let sit 15-20 minutes

2) Wash chain and cassette in soapy water.

3) Dry completely

4) Lightly spray wd 40 on the chain and cassette.

5) Lightly grip chain with rag and run through about 3-4 times.

Everyone says Wd 40 is a lousy lubricant.  But, when it comes to lubricant less is always more, and wd40 seems to lubricate the right ammount.

Using wd40 leaves my drive chain feeling quick and light.


When to change disk brake pads I was wondering how to tell when your disk brake pads need replacing.  My front seems to be not stopping as quickly as it used to, or as I would like. I know this could be road grime build up, but I am not sure the indicators for replacement time for the pads.

You should just pull the pads out and see how worn down they are - or if they are really dirty. Sometimes it helps to get some rubbing alcohol and clean the pads and rotors.

I never change mine until I hit metal on part of the pad. Hitting metal is probably the only indicator that accurately predicts the true state of wear on the pad. All the other "feelings" that maybe the brakes aren't performing as well as they used to are generally just based on the conditions they've been subjected to over the past few days (as OP noted). I've had pads that worked like complete garbage in the rain, and after I took them on a gentle downhill in the sunshine, worked amazing in all conditions afterwards. Side note - that's also how I get the screaming banshee sound to go away on a loud set of pads.

Basically, if you're noticing a difference in braking quality at the top of the pad vs the bottom, you should be very concerned about the manufacturing process that the pad manufacturer is using. There should be no difference between the top of a sintered pad (I assume the same goes for organic) and the bottom. As long as you have some pad material left over the entire area of the pad, you're good.

And yes, I assume that the OP has replaced pads by now :)


What is the purpose of a braze-on on the underside of seat stay? I have a Jamis Citizen 2 Step through (2013 or 14 maybe) which has a braze-on on the underside of the seat stay near the brake studs.  Just one braze on each side.  I'm curious as to what the intent is and what opportunities they enable.  I already mounted rack and fenders so I'm not talking about the brazes near the seat tube.  In the photo behind the link look closely and see the braze-on just on the inside of the back wheel.

Here is the bike:

http://www.myjamis.com/SSP%20Applications/JamisBikes/MyJamis/consumer/bike.html?year=2014&model=Citizen%202%20Femme&cat_grp=fem_11

Photo:

http://www.myjamis.com/SSP%20Applications/JamisBikes/MyJamis/consumer/images/fancy/14_citizen2step-thru_bl.jpg

Zoomed in photo highlighting the specific braze-on:

I'm not positive, but I believe those are for a frame-mounted wheel lock. These are locks that you mount to the frame in roughly that location that immobilize the rear wheel when locked. Typically they mount via the brake braze-ons or their own straps, but that location looks about right for a direct mount

An example of a fitted lock can be seen in this image:

This type of lock is convenient, but not especially secure, since a thief can always just pick up the bike and carry it off. Some do include a way to plug in a cable or chain in order to lock the bike up to something else, but those aren't especially secure, either.

I believe those are for frame-mount rear racks. While some can attach to the seat post, others can attach to the frame. The link shows an example:

http://www.bikebagshop.com/salsa-alternator-rear-rack-p-3187.html


How to fend off a pack of feral dogs I really enjoy riding. However, today I had a, truly, terrifyng experience. I was chased by three feral dogs. I was able to out pace them, but it it really left rattled.
I understand that if one acts like prey, one gets treated like prey, but I am conviced thise dogs would have have ripped me to shreds.  Acting dominant and standing one's ground when dealing with a domesticated dog makes sense. Standing up to three feral dogs aounds like a death sentence. My question then, is what should I do if I'm confronted with this situation again?
Thank you.

You did exactly the right thing by getting out of there.

When a dog commits to an attack, they make a beeline in the last part of their approach straight at the target.  One technique is to cast and ride easy till the animal commits and accelerates, then pour on the power and accelerate forwards.  Animal will pass behind your rear wheel.  One or Two pedal strokes is all you'll have time for.

Risks are that you suffer a mechanical problem induced by the extra power.  If there's ever a moment you don't want your chain to break, its right then.

Three working as a pack would be extra terrifying.  Smart dogs will herd you, and these sound smart because they're still alive.

The dogs will most of the time go for feet and ankles, shins/thighs, because they're moving and are at the lowest height.  The might aim for a forearm or hand because of the wide stance of a MTB.   Adding barends might act as a shield/barrier for the hands.  Wearing stout leather boots with steel or composite toe caps will help if the dog gets that close.  Leather chaps would make riding hard and hot and uncomfortable.

As for defence, some suggestions with their downsides

Kicking - we all have feet and they're already on the bike with you.  But by kicking you're not powering the bike, which takes away from getting away.
Water balloons in a front basket for easy access - throwing at a small moving target is hard enough when still, from a rolling bike would be much harder.
Water balloons filled with fake skunk - same as above, but you don't want to break one on yourself.  However you might be able to smash these into the ground in front of the dog.
Water bottle squirt - surprisingly effective, if you have enough for a blast.  Again, one had off the bars, and aiming from a moving bike makes it hard.
Stick or baton - a few sticklike things might help, but if you're waving a stick then you have one hand off the bars already, decreasing your overall power.  Plus swinging is likely to change your center of mass and make you wobblier and unstable.    If the dog gets a mouthful of the stick/pump then they can pull you over, and more so if its a nightstick or a baton with a wrist lanyard.
Long lightweight stick - I'm not sure what plants are in your region, but here we have toitoi and flax bushes that produce 1.5-2 metre long lightweight poles.  I imagine bamboo is available worldwide that will fit the ticket.  Downside is carrying it on your bike.  Possibly as a flag pole, or as a load fastened to your top tube with light masking tape for quick removal.  Waving this in the general direction of the dog should help, they are moving fast and sound "whippy", and any contact is going to sting.
Pepper spray / mace - its not legal in my country but may be for you.  This may be enough to deter a dog but you'd have to get it into the dog's eyes and mouth.  Again needs a hand off the bars to apply, so best left till a dog's got its mouth on you before falling back to this defence.
Knives - too short to do anything useful, but again may be good after the dog has bitten down.  Go for the eyes.
Swords - pretty much all the bad stuff from above wrapped up, plus they're just as likely to cut you, and swords are expensive, kinda fragile, and heavy.
Firearms - this seems like a really bad idea IMO.  Again mostly illegal in my country.

As per water balloons, you will struggle to hit a small moving target
The location may not be safe to fire
Having the weapon may make you take on a fight that you should run away from.
A shotgun loaded with shot would be a better weapon, but even then not something to carry on a bike loaded.

If you do wound an animal to the point it can't get away but is still in pain, then "putting it out of its misery" may be a bad idea.  Smart animals can fake it to draw you close, and then lash out.   The dog's companions may use this as a distraction to attack you from the other side.  Your top priority is you.

Feral dogs are not good - long term you need to report this and hand the problem off to those who can legally do something about it.  There's a chance they're domesticated but reverted, and there may be a microchip or a collar ID to identify the proper owner.

And having submitted a report, you have prior proof that something has happened and therefore an excuse for carrying an offensive weapon.

The location is important too.  If you're in a national park there may be restrictions about where you can be and whether you can carry any offensive weapons.

Action camera footage can be beneficial to corroborate your story, and can assist in identifying the animals.  I always ride with a handlebar camera, but you might prefer a shoulder or helmet or wrist-mounted one so you can aim the lens.   If nothing else, it can be good for the youtube upvotes later.

Carry a basic first aid kit and consider adding enough medical supplies to clean and bandage a bite or two.  Better to carry and not need, than to need and not have.

The best thing to do if approached by dog/s is to stay perfectly still.  It takes a lot of nerve, do not look at the dog/s teeth, the dog/s will sniff around probably take a leak then with luck, wonder off.

The reason for this behavior is, I'm informed, that a dogs vision is relative to movement.  What isn't moving does not impact its fight / flee senses.


Am I required as a biker to use the bike lane on the right side of the road? The following is a google maps image of a busy intersection I need to take during my commute:

Traffic mostly comes from 2 sides: the South and the West. At the time I pass this intersection, there is a lot of traffic from both sides. There are bicycle lanes on both sides. Most traffic from the south heads west (about 4 in 5 cars) and most traffic from the west heads east (again 4 in 5).

When I come from the West and need to go via Diepe Roet (that small curvy street to the South), there is a cycling lane up to the intersection. However, I find it hard to judge the traffic situation, because there are usually 4 or 5 cars waiting from either side, and they don't usually use their indicators properly. There's also not enough illumination to completely cover the intersection.

The solution I've found is to head north along Heistraat. If it's not yet dark, I try to cross at the Frans de Cortlaan, which doesn't have nearly as much traffic. However, there's not much light there either, so if it's dark (in the winter), I drive another 50 meters or so further North. There is a school there with clear illumination on both sides, no perpendicular streets, a long speedbump and a zebra crossing. Both crossings are in my opinion far safer to cross, because it's much easier to see oncoming traffic in both ways. After having had an accident in the dark when crossing at the marked intersection, I rarely cross at that street, except during the holidays when there's no school traffic.

However, I need to drive on the left hand side bicycle lane for this, and I'm not quite sure how dangerous or legal this is. I'm not the only cycler who does this on that intersection, and I feel like I got enough justification to do it. However, if I get into an accident, I could get into trouble for not following the normal flow of traffic.

Is driving against the flow of traffic an appropriate maneuver to counteract the danger on that intersection?

Riding against the flow of traffic is dangerous and illegal.

If an intersection or a set of intersections does not permit you to ride safely, walk your bike.

Always keep in mind the true purpose of segregated bicycle facilities. To keep bicycles out of the roads that motorists think belong to them. They are not built for safety. In fact they are usually more dangerous than riding on the road. I always avoid them and ride on the road instead, that is my recommendation.


How can I properly replace the hose on this older Schwinn pump? I have the following Schwinn bike pump. It’s pretty old, perhaps 30 years or more. I like it a lot.

Some years ago, I changed to Presta valves; for this I needed a new head. I got a Topeak SmartHead Bicycle Floor Pump Upgrade Kit, which is a replacement head and hose with a number of different adapters. Unfortunately, none of them fit this pump, so I just hacked off most of the worn-out stock hose and spliced in the Topeak hose (one of the adapters is designed for this).

Every so often, the splice begins to leak because the stock hose cracks a little. This is easily repaired by cutting off another 5mm and re-splicing, but obviously that's not sustainable.

Here are some close-up views of the threads, and also the gauge for ID purposes. That's a AAA battery for scale.

My question is: where can I find something that will screw into the threads in the base of the pump and somehow lead to a modern Presta pump head?

I think that the size of that thread is called, "1/16 pipe thread" Find local places that make custom hydraulic hoses and verify the thread.  Then ask whether they have a fitting that is 1/16 male thread by hose barb.  Then you could eliminate all of the 30-year-old hose.

This looks similar.  You could whack off the head and hopefully the hose inlet to the pump is the right size.
http://www.sears.com/custom-building-products-replacement-pump-hose-20inch/p-SPM6180332701?prdNo=10&blockNo=10&blockType=G10

It is listed as 3/16" hose connector.


My bike tire just started rubbing against the frame. Please help me fix it the problem is the back tire just started rubbing against the frame. this literally happened 30 min ago. please help me fix it!!

I'm going to guess that the wheel slipped in the dropouts (where the wheel's axle enters the frame).

Loosen the nuts that hold the wheel's axle in the frame. Push the wheel back into the dropouts all the way (depending on the frame, you might not do all the way; the wheel should be sufficiently in the dropouts). Check that the wheel is centered. Then, tighten the nuts.

or it just could be that you need to tighten your bearings and you have to take the tire off then the tube and the bearings should be on your rim that's what a bike shop told me to do cause my bike does it also.


Can the brake levers be moved from the side to the top of the handlebar? My bicycle currently looks like this:

Can I move the brake levers from the side to the front, so it looks like this?

How do I go about it, and is it good idea? I'm new to riding this kind of a bicycle and I feel very uncomfortable leaning so far to the front to hit at the brakes!

Not really. The levers in the second picture are commonly called "interrupter" levers, and are usually used in addition to the levers you've already got.

I think you'd find that if you simply tried to relocate your existing levers, they wouldn't fit against the tops of the bars very well, and the way the levers are curved would cause them to bump into the handlebars before you had fully depressed them.

You could replace your current levers with interrupters (at least some interrupters are designed so they can be used alone). I'd advise against that: riding from the "tops" of the handlebars can make handling a little dicey, and this would lock you into braking from a less-controlled position. You can ride on the brake hoods or the "ramps" just above them and still apply a fair amount of leverage to the brake levers while being in a position that's reasonably comfortable and controlled.

If your bike is the one shown in the top picture, you can also raise your stem. I think that if you give the forward position a chance, you'll adapt to it. If not, you can replace your handlebars with flat bars (you'd need new brake levers for that as well).

Yes, you probably can achieve the desired result, though not the way you described. Some bikes come with the standard levers, as shown in your first photo, PLUS additional levers that run parallel to the crossbar of the handlebars, exactly where you want them. Perhaps interrupter lever is another name for them, but extension levers is what I know them as.

Though not always the case, many, if not most, good quality brake systems can be modified by adding the extension levers as an aftermarket modification. Good systems use screws to hold the levers in place, so that they are replaceable. Those are easy to add extensions to.

If yours have rubber hoods on them, as in the photo, the modification includes punching a hole through those, so that the extension can be bolted on. If you bought your bike from a good bike shop, they should be able to do it for you in less than an hour, unless yours are not suitable for modification.

If, for whatever reason, you can't/don't want to do that, you can replace the entire lever system with one that already has the extensions, like this one; https://www.amazon.com/gp/product/B00LIFBEGA/ref=s9_acsd_zwish_hd_bw_bEf0F_c_x_w?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=merchandised-search-11&pf_rd_r=Y4C1DVZ2RBB2KN05YXVY&pf_rd_t=101&pf_rd_p=35be4e2e-4268-5a73-9f8b-dcbcdf18a280&pf_rd_i=3494211


Help with choosing an entry level mountain bike Me and my wife are looking to start cycling in the nearby nature. We aren't expert biker cyclers but are in reasonable shape (we're in our 20s). We're looking for two entry level bikes, each up to the price of 350 USD. The nearby nature includes mostly 4X4 paths, sometime narrower but in general in such a paved manner. Could anyone recommend good bicycles in this price range that will fit our requirements?

First of all, why do you want a mountain bike?:

  The nearby nature includes mostly 4X4 paths, sometime narrower but in general in such a paved manner.

This is definitely not what a mountain bike is for: They are intended for serious trail use, i.e. broken paths with lots of obstacles/debris. Given what you're describing and your beginning riding "style", I'd personally recommend either a lower-end touring or hybrid bike with tires more meant for off-road use: They will be more comfortable to ride for longer periods, will be easier/more enjoyable to ride fast (less rolling resistance) and can be easily used for stuff other than trail riding such as hauling groceries with a rack and panniers. Mountain bikes are a pain to use for anything other than, well, mountains†.

However, in order to get a new bike which you will really enjoy riding and can depend on for a long period of time without it breaking, you'll unfortunately have to spend a lot more than $350 USD (cf. a 2015 ranking of good entry-level mountain bikes, on which most start at around $500). Unfortunately, although bikes at e.g. Walmart may be in that price range, you will regret spending that much when just a few hundred more will get you a very respectable machine.

However, you can find a great deal on a used mid-range bike on sites such as craigslist: By buying used, you save the instant "drive it off the lot" depreciation which comes with a brand-new machine. If you don't know anyone who can help you find a good deal on a used bike, however (it's like buying a used car: be careful and always be ready to pay for repairs after buying it), many reputable LBSs will have a few used bikes for sale or will know someone who does.

† Although this recommendation is biased since this is my absolute favorite type of bike to ride, if you really are into doing mixed light off-road stuff like you describe, consider getting a so-called "adventure bike", which is basically a road bike for people who aren't afraid of getting dirty. These bikes are ridiculously fun to ride on nearly any surface and you can still carry groceries with them when needed.

First of all, mountain bike riding is a great thing for a couple to get into. A great entry level bike for around $350 is a Giant Revel. It is considered an entry level bike because it doesn't have disk brakes and only has front suspension, which is all you will need for your kind of riding. I started out with this bike and had no problems with beginner riding. I later upgraded but I feel like this bike would be the best fit for you guys as of now.


The best way to deal with/prevent punctures on tubular tyres I recently picked up some rather expensive tubular wheels on the back of a lot of advice to do with rolling resistance, comfort etc. However I've recently found I'm quite afraid to use them on long training rides for fear of getting a puncture in the middle of nowhere. I'd like to know what people do to prevent/deal with punctures on tubular tyres.

You could try adding sealant to your tubular tire.

Tufo Tire Sealant, Stans's No-tubes (and other tubeless sealants) can be used to deal with small punctures. Most recommend not using the sealant as a preventative measure, but more so as an after the fact solution to quickly fix punctures on the road.

However, Tufo Standard tire sealant says that it can be used as a preventative measure, but I can't speak for this. I've heard that it could affect ride quality, so it may be best used in a roadside emergency.

Use puncture resistant tire liner like that one:
http://www.flowbikestore.com/band-zefal-puncture-zliner-blue-26


How can you recognize a department store bike? You can obviously avoid department store bikes by buying from reputable local bike shops, but how can you tell whether a used bike is a department store bike? Are there any telltale signs? I have a friend who is looking to buy a used bike, and I would like to tell him what to look out for.

As per @Mikes Answer, but a bit more than fits into a comment.

Only buy a bike with the brand/model of major components able to  be researched.

On a Mountain bike, shocks are a dead giveaway, and if rear suspension, look at the shock, although they sometimes don't have a model, the good ones always have a brand. From there, pictures will get you close enough. Also look at the geometry - if it looks like a light weight motorbike it's rubbish (Unless it's a top end down hill rig)....  keep in mind age makes a big difference here, so search teh internet for parts of similar ages.

Brakes - Disk brakes should have a brand/model than can be researched. Rim brakes usually have something, but it's always a bad sign if not.

Seat / Seat post - worth a look, not a bad sign if no brand.

Drive train components can be tricky, many shops put an expensive rear derailleur on an otherwise cheap bike (That is all many people look at). Look at the cranks, the front derailleur, the shifters etc. These will usually have model information somewhere.  Wheels and hubs - again look at the brand/model - most came out with labels.

One useful guide is overall weight - lighter bikes cost a lot more. BUT make sure you compare like for like. No point comparing a carbon frame to a steel frame and assuming the carbon is better because it's lighter.

For a novice stick to a brand/model that you can get the details off the internet. Look for a bike that has signs of light or no use. Everything should work smoothly and reliably. No groans, squeaks, clattering of any sort. The problem is any of these can be a sign of big money or a 2 minute tweak to fix and it takes expert eye to tell the difference.

91 mm front dropout dimension indicates cheap front hub.


What do you do if you find your stolen bike's frame on ebay? I am 85% certain that I see my bike's frame on eBay. It costs almost 2k with all the components and I see the frame on sale for $400 with seat-post and fork only. All my stickers not in the pictures(3) however the frame is the same size and picture only shows the side with no identifiable mark.

The frame itself is rare, not expensive but the brand is not widely sold. And if its sold used, its almost always a complete bike. The manufacturer doesn't sell frame only.

It was stolen, from a bike rack, in open daylight in downtown in big city, I suspect that I forgot to lock it. Lock was on the frame and so was my helmet. I reported the bike stolen on bike index and did file a police report. And posted the bike on local FB groups for stolen bikes.

It is now on sale on ebay, 5 days after about 100 miles away from where I am. Item says local pickup only?

UPDATE: I am now less certain that it is indeed my bike. More like 40%

To determine if the bike is indeed yours, you could contact the seller and ask for more information about the bike and for more pictures in the hope that you'll get one with a visible identifying mark.

You'll need to be careful. If the seller know's it's stolen asking for more information and pictures could tip them off that you are the rightful owner with the intention of retrieving your property.

You should read the Ebay Stolen Property Policy for what to do if you are convinced the bike is in fact yours.

Buy it.

You'll get your bike frame back quickly.

Once you've identified it, you can choose to make a police report, but the chances of a prosecution are probably very low anyway.


Shimano 11-Speed Freehub onto 10-Speed Hub I have Dura Ace 7801 10-speed wheels.  Can I install a Shimano 11-speed free hub onto the 7801 hub?

No for a whole lot of reasons, the most decisive of which is that the 7801 hubs are among the only (along with WH-6600) ones Shimano's ever made that use a drive ring in the hub shell to engage the pawls, as opposed to the pawls and the ring they engage being all internal to the freehub body. In other words the design is completely different from any of the 11-speed freehub bodies.

The hub design from WH-7801:

An 11-speed FH-9000 Dura Ace, for comparison:

If this is one of the 20-spoke carbon 7801 wheels that take standard nipples, you could just swap in a new hub.

As for the larger discussion of whether this is possible with Shimano hubs:

Among the Shimano hubs that use a standard M10x1 axle, until 11-speed came along there was a frequently re-used, semi-standard 10-spline attachment scheme for the freehub body, so in many cases there is some freehub body interchangeability, at least in a pinch as there are some other considerations involved to make it work well. (The nonstandard/oversize axle hubs, which are numerous at this point, generally all need the exact replacement freehub body, although there may be some exceptions or hack possibilities now or in the future.) However, the 11-speed hubs using standard axles that have so far been released, FH-5800 and FH-CX75, use a version of the same design that has 15 splines on the hub shell instead, meaning no interchangeability with a shell with only 10 splines.

FH-5700, 2nd generation of 10-speed 105. Freehub body attachment representative of many other Shimano hubs:

FH-5800, 1st generation of 11-speed 105:

You absolutely can put a 11S cassette on a 10S hub but you will need a little help.  Dura ace, Ultegra, 105, Force and rival cassettes can be modified to perfectly fit a 10S hub.  The Wheel stays intact, no modification needed on hub  re-dish of the rim.

The back of the cassette needs to be machined by a qualified machinist.
All 11 speeds are 100% functional like they should.

I have been doing this for a year now and I am getting 100% satisfaction from my clients.


Rear derailleur noise in big/big combination Every Google search I've done over the past weeks has landed me on this great forum, so thought I would register.
Basically my son gave me his 1996 Scott Apache adventure mountain bike in a box and I've rebuilt it with new bearing, cables etc.

The problem I have is the chain seems to be rubbing on the side cage of the derailleur,  only when it's on the high front and rear cogs.
The chain is two links shorter that the original which was to badly rusted to re-use.
Old chain = 110
New chain = 108
I did rap the new chain around both large cogs and added two which gave me the 108.
Here's a couple of images:

Drive trains with a front derailleur system are designed with to have overlapping gear ratios ranges for each front chain ring to allow you to spend most of your time riding with the chain not stretched to the extremes of your rear cassette.  Riding in your largest gear on both your front and rear is call Cross Chaining.  Cross Chaining puts unnecessary stress on your drive chain system by forcing your chain to work through extreme angles to propel your bike forward.

Additionally, you'll get a grinding noise when using the most extreme gear combinations as you are forcing your chain to go from front to extreme back.

Best best to avoid that sound is to practice shifting both your front and rear derailleur.  Starting out, it may feel awkward but your bike and ears will thank you ;-).

It is worth spending some money at the mechanic to give it a good inspection to make sure everything is in safe working condition as well.  Nothing is worse than having something break when you are riding.

Sometimes the chain can make contact to the derailleur and so make a noise. Sadly, there are certain gears one should travel. These include everything except the combination of a small cog back with big cog front, small cog front with big cog back. If the derailleur are poorly adjusted, this can be the cause of the chain having some friction with the derailleurs. There are two solutions. Either you do not ride in these gears or you have it properly adjusted.


Is there any advantage to using pedal straps over clipless pedals? Other than not having to buy special biking shoes, is there any clear advantage to using pedal straps over clipless (aka clip-in or step-in) pedals?

The biggest benefit I see is convenience.  You can just hop onto a bike with whatever you're wearing at the time and go.  Not a big deal if you're planning a 15 mile ride, but a real big deal if you're riding around the neighborhood, hopping off to run into a few stores, etc...

It's also possible to pedal on the flip side of the pedal and get moving without the cumbersome and slow start up that is required to get into clipless or straps.  In an emergency you can even stomp on the straps and move the bike out of the way.  It's rare, but occasionally you find yourself standing there and just want to get out of the way, in any direction.

I've now switched almost entirely to riding clipless though.  Between that and riding fixed gear, it makes the bike feel so connected to me.

To compare:
Straps are easier to get into.
Clipless are easier to get out of (really!).
I've never pulled out of my clipless pedals, I have broken a strap (no big deal if you're not in a sprint).

At this point if I'm riding any distance at all, I change shoes.  If I'm just going to the store to pick up groceries, I don't even have straps, just old school pedals.  The middle ground for straps just evaporated for me.

Strapped-pedals are generally frowned upon for some strange, unknown reason. However, I would do away entirely with them, and instead, make sure I'm using correct foot positioning. Correct positioning on the pedals is pretty much all the clipless shoes achieve, aside from slight raise from pedalling too, but this advantage is somewhat negligible.

I went clipless, and loved it, great for pure power riding. Then I went to straps and found it a pain trying to get the straps to the right tension where I could pull my foot out and push it back in with ease.

I then went back to standard metal-teethed pedals and a foot positioning similar to clipless pedals and then wondered why I even bothered with the others....

It's personal opinion really, but I'd say scrap both of them. :)


Shimano 8/9/10 speed freehub conversion to 11 speed does not appear possible due to changed spline pattern After remaining unchanged (with a few exceptions like FH-7801) for nearly 20 years the Shimano freehub body spline mount has changed along with the width.  I had hoped I could refit a 8/9/10 speed rear hub (FH-M756) to work with 11 speed.  But the mounting face on the 11 speed freehub body is totally different compared to the old 8/9/10 design.  I don't see any hope in retrofitting old hubs with new freehub bodies.  Anyone found a solution short of hub / wheel replacement?  The "Zinn" filing down method seems to be the only hack available for standard Shimano brand hubs.

FH-M756 freehub body Y3BD98010 cannot be replaced with FH-6800 body Y3CZ12000 (see photo).

There is no remotely practical way of doing it. It's possible that could change in the future as 11 trickles down more, but probably not likely given that the interface is also different on the standard axle, less expensive 11-speed road hubs they've already made.

Just to be clear though, 11-speed MTB cassettes do not require a new longer freehub, because the large cog overhangs.

My Sram 11 speed PG-1170 fits perfectly on my Shimano FH-6400, the only problem is that the thread on the lock ring is too short and doesn't reach the hub; I think I will get somebody to make me a custom lock ring.
P.S. the Shimano FH-6400 tricolor was the most beautiful hub Shimano ever made!


What is the safest and most courteous way to ride on a two-lane road? There is a one-mile two-lane road close to my home with no bike lane, but with a large sidewalk. I ride this road every day, and it got me curious what I should be doing. The speed limit is 35 and the roads are pretty empty except during rush hour.

Most riders either stay close to the curb like below.

And I have noticed that cars pass them on the left, and it seems very unsafe to me when there is another lane.

Other riders use the sidewalk like the below. But since there is a lot of foot traffic and trees and such you would be very slow.

And I do the below.

I hog the whole lane so no cars pass me on the left. I average around 16-18 mph on this road, and it's only a mile long. Most of the time it's fine, but during traffic I feel like am not courteous.

And once in a while there are cars parked although very rare like the below. Which I really like because the whole lane is for me, and I can go around the cars.

I use the method in your 3rd picture - I take the middle of the lane when there are no bike lanes. I am helped in these cases by the fact that these roads in my city usually specify the right-most lane as a shared car and bike lane.

Besides the speed issue you state when riding on the sidewalk, it is also hazardous for both the cyclist and pedestrians.

I feel that riding far to the right, while still in the lane, just invites cars to pass you even when there isn't enough room.

Taking the middle of the lane is my way of encouraging them to overtake the proper way by fully moving into the left lane.

The most courteous thing to do is to make sure that an old lady crossing the street doesn't have to get her ankles wet, by covering the mud puddle with your jacket.  Of course, that's an extreme courtesy, but it does leave your jacket muddy.

I've heard of people describing Internet connectivity in the 1990s.  People often had a choice between reliable, fast, and cheap.  They were allowed to pick any two.

Reliable and cheap - dial-up over phone lines.  (Not fast.)
Reliable and fast - T1 lines (they were fast in the day).  (Ridiculously expensive; businesses may be able to afford them.  Most homes wouldn't.)
Fast and cheap - Internet provided by the cable TV companies.  (Often went very slow, or even was non-functional, at certain times of the day.)

Those were the widely available options at the time.  None of them offered everything desired.  Sometimes, you just have to make a choice.

In the case you're describing, you have identified possible solutions (safe, or courteous).  Now you're asking for the solution that provides all conceivable benefits.  Sometimes, that might not be an option.  You may need to make a choice.

In your case, you can choose between riding towards the right side of a lane and letting people pass you more easily, by causing them to only swerve over by a partial lane.  Or you can choose to ride down the middle/left of a lane, in which case the car will need to swerve left by 80-90% of a lane, and will probably just decide to do a full lane change.  That is less courteous.  It also makes them far less prone to drive so close that their mirrors touch your handle bars.  If they move over a lane, and then something went awry and your wheel (and handle bars) suddenly turned left unexpectedly, the chances of a collision may be rather low, instead of being almost certain.

Are you willing to be a bit less courteous?  I try to be courteous when it is sensible.  I often open doors for people, at some detriment to myself as I stand outside.  However, I'm more willing to let an old lady risk getting her ankles muddy, than to go through the entire rest of the day with my jacket being dirty-wet just so someone could enjoy using it as a floor mat.

For myself, I've gotten into the habit of taking up more of the lane, because I've decided that my own safety is sufficiently important.  Letting somebody else feel more comfortable with moving over less far is not worth the much higher chance of me becoming permanently injured.


Is cyclocross tire (CX) taller than normal road bike's? According to the specialized website, the 54cm crux 2021 comes with 700x33c cx tires.
https://www.specialized.com/us/en/s-works-crux/p/171342?color=271648-171342&searchText=91420-0046
And, its bb drop is 69mm and its bb height is 283.5mm.

That means its tire height is 41.5mm?
My current 700x25c's tire heigh is 25mm and I also ride a 700x44c and its height is about 40mm.
So, did I make wrong calculation? or CX's tire is taller than normal road bikes?
The calculation is
( ( 283.5 + 69 ) * 2 - 622 ) / 2 = 41.5

BB height is a measurement that depends on too many ill defined parameters to be useful.
A rough approximation for three height of a tyre is to take its nominal width. That leaves us with a discrepancy of about 8 mm. Spezialized seem to have used either a height from the tyre manufacturers data sheet or actually measured themselves.
Tyres deviate from a perfect toroidal shape. For example, a fully inflated tyre on a narrow rim might be much taller. Rim and casing will determine the actual cross section.
There is also a layer of thick rubber to roll on and, in the case of the CX tyre knobs.
Lastly, for a real measurement one has to consider tyre drop* of the tyres. For road riding up to 15% is typical. CX tubular tyres might be depressed by 50% however.
Finally, Spezialized's road section might use different conveniens l conventions than their CC section or MTB section.
Overall there is so much guesswork in interpreting that value that you might only find out that BB height means by asking Spezialized themselves.

Tyre drop is a measure of the reduction of a tyre's extension in radial direction under a radial force oriented towards the hub.

There are several things that may be at play here.
Tires bulge like a balloon out of the rim. Thus, tire height in general is more than tire width because tire is higher than a half circle. So it is untrue that a 25mm wide tire is 25mm high too.
Firstly, most road tire purchasers look at tire weight and make a purchase decision based on the tire weight. Thus, your current 700x25c tires may actually not be 25mm wide but they may be 23mm wide instead. By selling a 23mm tire as a 25mm tire, the manufacturer is able to make it lighter than its competitors. Soon every manufacturer starts to do this to gain the same benefit of light weight, and we have lots of tires sold with incorrectly marked size. This would mean that 23mm tire is 25mm high, i.e. tire is 8.7% higher than it is wide.
If you take this effect into account, 33mm tire should be about 36mm high.
Cyclocross tire manufacturers do not have as large incentive to sell tires with incorrectly marked size, because cyclocross tire purchasers do not make decision on the weight of the tire.
Secondly, cyclocross tires have knobs. They do not contribute to width but contribute to height. If a 33mm wide tire which is 36mm high has 5.5mm high knobs, the tire total height is 41.5mm.


Does the valve have to be straight when replacing a tube? I've just replaced the tube on my bike and when I pumped it the valve wasn't particularly straight as can be seen in the image below.

What I'm wondering is do I need to remove the tube and straighten it before use? I assume it wouldn't be any harm to do so but if there is nothing wrong with the way it is I'll save myself the effort. I'm going to be cycling it in the morning so I said I better ask before I do.

It should be straight out, perpendicular to the rim. Otherwise you risk damaging the tube.

When the valve stem is at an angle the valve isn't free in the hole – it is trapped by the edges of the hole where they bind the stem. The edges of the hole may cut the stem which will be moving a little bit as the tire and tube flex over bumps and the like.

There will also be an area of the tube that isn't supported by the rim (or that is stretched more than the rest of the tube) near the valve stem. That area is likely to be a weak point in the tube.

And one more thing! As pointed out in the comments below, there are conditions – such as the tire moving on the rim – that are likely to further stress the tube as it passes through the valve hole. If the valve is initially straight any angle of the valve is an immediate sign that something is happening.

If you're hardpressed or in a hurry or it's a big job risk it,  buy another tube so that you're ready for when it sooner or later fails, or when you need to replace the tire.


How do you fix a puncture on tubeless tires? I recently got a new bike with a set of tubeless compatible rims. The stock tires are clinchers with tubes. I'm thinking about putting tubeless on there, but I don't have any experience with them. We have some trees here that drop huge thorns, like nails. They're big enough to go through any tire. When I get the eventual flat, how do I fix the tire? Are there patches? Can you just stick a tube in there?

When putting tubeless tyres on I would definitely recommend that you use a sealant such as Stan's if riding somewhere with thorns. This would be your first level of defence. The sealant would seal up a thorn (or other) hole quickly and painlessly.

You can repair a tubeless tyre with a vulcanizing repair kit, but reseating a tubeless on the trail is very difficult. It is virtually impossible to do without 'shop air' (I haven't tried CO2) so carrying a tube is important for any major leaks.

You can simply run a tubless tyre with a tube until you get somewhere to properly fix the tyre.

Like everything else in the mtb world there are two schools of thought on whether you leave the thorn in or remove it, I would remove it. If you leave it in it plugs the hole but then if you ever do need to put a tube in you risk puncturing that also.

None of these work. All are BS.  If you have a punctured tubeless tire. The only fix is a new tire.

Sorry.


Which rotor, Steel or Titanium comes with Avid CODE brakes? I just bought Avid CODE brakes. It comes with a rotor (200mm). I checked the website and manual and I can't find out if the rotor is stainless steel or the titanium version.

How can I tell?

Information printed on the rotor.

200mm HS1
BOLT TORQUE 55in-lbs 6.2N-m
A01 SEP 11

If a magnet sticks, it's steel.

Happy riding.

You know, if you take a 2 inch ball made of lead and a 2 inch ball made of brick and submerge them in water, they will both displace the same amount of water, since neither will float. But Ill bet their weights are worlds apart. You probably meant to say.."Place it in a measuring cup FLOATING in water", then you can figure out how much water they each displace.


Why don't road bikes use v-brakes? In my experience, linear pull brakes (v-brakes) have more stopping power than other types of cantilever brakes (let the flames start ;). Modern road bikes always come fitted with dual pivot brakes. There isn't a massive difference in weight (Similarly priced XTR v-brakes @ 400g (F&R) VS Dura-Ace dual pivots @ 314g (F&R)) so I'm wondering if there is another reason why road bikes don't use linear pull brakes?

Is it to do with 'feel'?
Are my road
brakes rubbish, and most sets are
actually as powerful as v-brakes?
Obviously, current road levers
wouldn't work (well) with v-brakes..
Is it a pure legacy reason that
v-brakes aren't used?

It may be tradition, and it may be aerodynamics.   Note that some roadsters do... Touring bikes have gradually been switching from the traditional cantilevers to V-Brakes.  It's for tire clearance mostly.
"Good" caliper roadster brakes are very powerful; A set of high-end Shimano jobs (105 or above) will lock your wheel and they are routinely used by pro road racers.
They have a minimal aero profile and contribute little drag.  They also look good on a sleek roadster.
Also, you don't have to weld or incorporate lugs onto your snazzy carbon-fiber fork legs and seat-stays, which results in a "cleaner" appearance and less weight as well; high-end roadsters are all about weight, as you likely know.

Any brake design can give all the stopping power you need.  It all comes down to efficiency and mechanical advantage.  There is the issue of predictability.  The thing that doomed the old Campagnolo Delta brakes was their lack of feel and predictability.  Braking into a corner on a road bike you need to be able to decelerate as quickly without locking up.  On mountain bikes we often intentionally skid the rear wheel to get the bike around.  I tend to finess road bike brakes but toggle mountain bike brakes between on and off.  Personally I find modern dual pivots to be harder to modulate than the old single pivots but that is probably because I have many more miles on single pivots.  In any case, rim bikes on bicycles are long outlived their usefulness.  All serious mountain bikes have disk brakes and I'd wager that within a few years all serious road bikes will have disk brakes as well.  Disk brakes are better in every way than rim brakes.  More power, better control, less maintenance (for good ones anyway).


What are the benefits of cycling gloves? So cycling gloves? I don't see how this can change my experience of riding bicycles.

Someone please explain what benefits I get from them. Maybe I would buy some if the benefits are good enough.

All sorts of reasons:

Less damage to your hands when you fall off.
Vibration dampening.
Somewhere to wipe snot/sweat.

In practice, I use them when I am touring (long distances in the saddle - so reason 2 above), and when I am mountain-cycling competitively (reasons 1 and 3), but don't wear them when I am on my daily commute.

So cycling gloves? I don't see how this can change my experience of riding bicycles.

Try riding in temperatures around or below zero degrees Celsius without warm gloves. Then you'll understand how gloves can totally change your experience.
However, not all gloves are warm enough. You'll have the same freezing experience with marginal gloves than you'll have with no gloves.

Someone please explain what benefits I get from them. Maybe I would buy some if the benefits are good enough.

In the winter, they prevent your fingers from freezing.
In the summer, the benefits are much less and you won't be using warm winter gloves in the summer anyway. The ability to wipe away sweat to prevent it from getting to your eyes is useful, however.
Long ago the cycling cap prevented sweat from getting to your eyes, but then somebody decided that cycling is DANGEROUS!!! and shouldn't be done without styrofoam hats that supposedly prevent head injuries. Then we're left with no cycling caps and the only mechanism from preventing sweat to getting to your eyes is regular wiping with cycling gloves.


When to change winter tires for bicycles At work, we discussed when to change to winter tires for bicycles (and cars). We assumed that temperature was the key factor and I used a program (Mathematica) to check the mean temperature in Stockholm (see this question Probability of ice in Stockholm).

My question is: besides the risk of ice, what are key factors for deciding when to change from summer tires to winter tires? E.g. is the rubber of summer tires negatively impacted when it gets colder.

The cost of burning through studded tires can start to add up. I find it more efficient to keep a pair of studded tires installed and ready to go on an older pair of wheels, and I can just throw them on if it looks like it's going to be an icy day.

The first day of Winter (or winter solstice) in the northern hemisphere is usually December 21 or 22 every year. However, depending on the conditions, you may want to change over to Winter tires well before that.

Depending on the year, a slurry of other factors, and your location you may get snow and ice well before then. You should make an earnest attempt to have changed your tires at some point before you begin to see snow and ice material forming in your area.

You may want to have a look here for general tips on winter riding.


former weightlifter turned triathlete repeatedly breaking hanger Every year, it seems I am on a training ride 5-10 miles from home and while torquing up, I snap the hanger throwing the rear derailleur into my spokes and locking up my rear wheel. I am 205lbs and 5'10" and still squat pretty heavy so I am wondering if the combination of my weight and my force is wearing out the hangers quickly causing this and if there is a known way to check this for fatigue before I get on the road. I use a 2012 GTR Series 5 aluminum bike. If I ask at a bike shop, they will just try and sell me a tri bike. I want a tri bike but I don't want one if it wont change anything in my sprint and olympic tri experience.

The way you asked the question, it sounds like you think the following is happening: first, the derailleur hanger wears out/weakens, then it snaps, and this causes the derailleur to go into the spokes.

It is much more likely that the chain of events is the following: the derailleur is mis-adjusted, when you shift to the largest cog on the rear, the derailleur goes into the spokes, and this causes the derailleur hanger to break off.

Possible causes:

the inner limit screw on the rear derailleur is too far out, needs to be tightened a bit, until it reliably keeps the derailleur from moving too close to the spokes
the chain is too short, and when you shift onto the largest rear cog and the largest front chainring (not recommended in general), the chain gets too tight and this rips off the derailleur.

I had this exact experience the first time I tried going up a significant slope.  The bike was fine all the way on the flat, but as soon as the grade increased I was putting a lot more force into the transmission.

I heard the spokes going "tink, tink-tink, tink" as the edge of the deraillereur tapped the spokes.   That was the warning that I did not recognise.

At the steepest bit, I pushed really hard in bottom gear, and the cage of the bottom jockey wheel caught a spoke, and wrapped itself up towards the brake.

After going home, the fix was to put a beefier hanger and derailuer in place, and it did not flex under load as much as the old tinny hanger.

Summary: Hearing tinking noises is a warning, don't ignore it.


How to get a very tight tire back on the rim? I needed to change the tube as a consequence of a flat tire and I am in the situation that it's just impossible to put the tire back on the rim.

In almost ten years of experience with road bikes and MTB, I never experienced this.

I tried to use any possible tips, for example from the question How to get the tyre back on to the rim easily?

Every time I try, I end up pinching the tube and it's just impossible to put the tire in. How can I fix this?

I am hypothesizing crazy things, like: dilatation of the rim, need of industrial tools, ...

Edit (to address Neil's question): the troubles are given by a 700x23c tire on a 700C rim of a fixed gear.

The above video shows how to fit a tight tire / rim combination. Although it shows the Marathon Plus tire, it applies to any tire.

The crucial point he makes on the video is that the tire bead doesn't stretch and is the limiting factor in getting the tire on. Thus you need to push the bead into the well of the rim on the sides opposite to the last bit you're trying to get on. Doing this gives you the room you need to get the last bit on.
The extra room will make it easier and you will be less likely to pinch the tube. You can use straps to hold the tire in place if you need to.

I have the Marathon Plus tires and it used to take me an hour of frustration and sore hands trying to get them on. Using the technique in the video it takes me 5 mins like any other tire.

Assuming that you're talking about clinchers? And that you've either replaced or patched the tube.

Here's what you do.

Put one side of the tire back on the rim.
Insert the tube into the tire.
Now, snap the tire into the rim.

Ok? Now you're left with a section of tire/tube that won't cooperate?

So, here's what you do.

Sit with the wheel assembly between your legs, put your thumbs on the rim and your fingers on the tire, and "pull" until the tire locks onto the rim.

At that point, after inflation, you should be good to go.


How can I prevent my next bike from being stolen? I park my bike in my building's bicycle room, in the parking garage in the basement.

The garage door can only be opened with a remote fob, and the bicycle room is locked as well.

In the garage, I secure my bike using a U-lock, and a chain lock.

This morning, I came to find a hole in the door, and the two locks cut by what looks like an electrical saw.

What can I do to avoid that should I buy a new bike?

That sucks. I'm sorry that your bike was stolen.

If thieves are willing to break into a locked garage, break into a locked and fully enclosed mesh bike parking area then cut two bike locks using power tools: there's not much you can do about it.

If there are lots of bikes in the bike parking area you can make your bike a lower priority target by increasing the number and strength of the locks, and by making the bike itself look less desirable.

Looking at the first picture, it seems the bike parking area door could be easily opened from the inside. The thieves were able to cut a hole in the door and reach the door release - not the most secure setup. Also, it's likely that someone let them into the garage - i.e. one of your neighbors.

Just store your bike in your apartment if you can.

To prevent your bike being stolen, you could encase it in concrete. But I think you mean how do you keep it secure whilst also being able to ride it. If thieves have good power tools and expertise, they can cut through anything unattended, so if you keep your bike under 24-hour manned guard, this opportunity will never arise. Mere CCTV won't be enough. By the time the alarm is raised and someone attends the scene, the bike will be gone, and you'll only have a video of your bike being stolen as a consolation prize. Hiring guards to watch over your bike could well be more expensive than the bike, so you could take in lodgers so your home is never unoccupied; they watch over your stuff, and you watch over theirs. You could also keep your bike watched on campus or at work by taking it into the building and either locking it to a fitting in a staff-only area, or parking it near your desk or in another area frequently only by immediate colleagues.


Disc brakes squeak on Trek mountain bike I have a Trek 3900 mountain bike with disc brakes, and I just took it out of winter storage to start riding it for the season.
Everything works well, except for one very annoying problem: when I stop the disc brakes make an extremely loud obnoxious squealing sound. Any ideas of what is causing this?
Thanks

The easy thing to check is whether the pads have got a little damp while you weren't riding it. The solution there is to ride it a bit. If the noise bothers you try riding with the brake slightly on to heat it up.

Unfortunately that conflicts with the other problem: if there's oil on the rotor you should clean it immediately and avoid using the brake until you can clean it (to avoid getting oil in the pads because they're hard to clean). Wipe the rotor with either disk cleaner or rubbing alcohol and a clean cloth. Keep doing that with new solvent and new cloth until no further dirt comes off the rotor. Then take a quick test ride, using the brake. Ideally pedal hard with the brake on, so you heat the pads and rotor (and also get an idea of whether the brake works). Remember that riding with the brakes on heats up the rotors - be careful touching them immediately afterwards. Wipe the rotor with a clean cloth to remove any pad goop.

If there was no squeal last summer the alignment should be fine. The way to check is to look at the gaps between the pas an rotors. Check from a couple of different angles, the pad should be parallel to the rotor from all angles. If it's not try squeezing the lever - some pads pull slightly off angle when they come off the disk.

If all else fails buy new pads, clean the rotors then install the new pads. Remember that the new pads will need a little running in.

If you do shortish rides 20-40 mins grab a spray bottle and spray the brake rotors very lightly tho. It should stop for that period of time if it doesn't stop then it means your brakes are contaminated.


Sudden tyre deflation with no puncture At the start of my ride yesterday I was passing through town slowly and crossed a section of cobble stones (just a line running across the tarmac). I managed to hit the one cobble sticking out of the ground. I lost a lot of tire pressure (I normally ride 23mm tires with 90-95 psi, it dropped to around 20 psi) and thought I had gotten a pinch flat so turned back home to change tube. When I got home I tested the existing tube (in the bath tub) for holes and found nothing, I've put it back in the wheel now and reinflated, got through a 50 km ride yesterday evening and still inflated this morning...

Any ideas what happened? Is this a common (or at least not entirely unheard of) occurrence for others. The valve was closed and it's not the first time its happened to me either.

Here's the offending piece of cobblework, it's nothing extreme...

Three possibilities that I see

You did not suddenly lose air you just did not notice until you got to the cobble stone
The rubber tube failed and recovered
The valve failed and recovered

No so sure you had a sudden loss of air.  If the tire when from 90 psi to 20 psi in a short period of most likely you would have heard that.

Since the valved is the only mechanical device I going with valve failed and recovered. Either random or by force of the cobble stone the valve unseated and before it lost all air it re-seated.

I am definitely ruling out rubber tube failed and recovered.

If this has happened to you before on that tube then I would replace the valve or tube and valve.  If this has happened to you on more than one tube/valve then wow - it has never happened to me.

I agree with the comment a patch could fail and then recover at a lower pressure but if you were able to air it back up and hold I would rule that out.  My mountain bike was down to 20 psi once and tube only at low pressure could not find a leak but with tire on at 50 psi it did leak (at a patch).

See picture below. The little gasket may have deformed or it has a little slit that is held together with compression.  Another possibility is the the valve itself (not the knob) is not screwed all the way in.  Where you see the flat spot on the the threads screw that in with pliers.  I had a set of tubes that by unscrewing the pump some times the valve would unscrew so I would use a dab of thread lock.  I think that is actually a picture of a presta valve that the core does not remove - so screwing that in would do no good.

Same thing happened to me, but I discovered that someone had let the air out of my tire.