HDTenEightyP/NetNews huggingface dataset:
From: seligman@CS.Stanford.EDU (Scott Seligman)
Subject: Re: Another annoying lighting question
Organization: Stanford University
	<168956B4C.MEDELMA@cms.cc.wayne.edu> <Bx7CpL.759@watserv1.uwaterloo.ca>
	<1992Nov7.015556.18503@inmet.camb.inmet.com>
Date: Sat, 7 Nov 1992 22:23:59 GMT

In article <1992Nov7.015556.18503@inmet.camb.inmet.com> lenny@inmet.camb.inmet.com (Len Goodman) writes:
> 
> Does anyone understand the relationship between the different ways to 
> measure light output from a bulb: watts, lux, lumens, candlepower, candela,
> plus any others you can think of.


The energy used to power a light is usually measured in watts.  It's 
the product of the voltage and current used to run the bulb, both of
which are more-or-less fixed for a given bulb.

Luminousity is the amount of energy emitted by a light.  It is usually
measured in lumens rather than watts.  All else being equal, if you
put more watts in, you get more lumens out.

If the output of a light is focused in a narrow spotlight that you
shine in your face, it will appear brighter than another light with
the same luminousity that is more spread out.  A candela (also called
a candle) is a measure of this brightness.  Two identical bulbs with
different reflectors will consume the same energy (watts) and have the
same luminousity (lumens), but the one with the narrower beam will 
hurt your eyes more (candelas) if you stare directly into the beam.


Scott Seligman

Internet:  seligman@CS.Stanford.EDU
UUCP:      {uunet,decwrl,sun}!cs.stanford.edu!seligman
Packet:    kc6ock @ n0ary.#nocal.ca.usa.na
Newsgroups: rec.bicycles.tech
From: jimu@orthanc.cs.su.oz.au (James Uther)
Subject: Gear racks for MTB?
Reply-To: jimu@orthanc.cs.su.oz.au (James Uther)
Organization: sydney university
Date: Sun, 8 Nov 1992 23:30:15 GMT


I'm looking around for a rear panier rack for my mtb. It'll be used mainly
for gutter-jumping around the city with a moderate load, and sometimes for
longish tours miles from anywhere with heavy load. Does anyone out there
have any sage advice they could offer me? Blackburn seems to be the best
bet, probably the rack1. Anyone had bad/good experiance with this rack?
	thanks heaps and paghty
	james
Newsgroups: rec.bicycles.tech
From: richard@pegasus.com (Richard Foulk)
Subject: Re: Glasses mounted rear-view
Organization: Pegasus,  Honolulu
Date: Wed, 11 Nov 92 16:45:05 GMT

>HE>A few years ago I saw an ad for a cyclist's rear view
>HE>mirror which clipped to a glasses frame. I didn't
>HE>follow it up at the time, but now some my ride to work
>HE>is in heavy traffic and would like to try one. Does
>HE>anyone
>
>HE>1. Have any experience with these?
>
>I got such a device a year or so back, and used it for perhaps a week.
>Don't know if my experiences were typical.
>
>Problems:  you get a _very_ limited view of the road behind you, and
>what you see depends on the angle of your head -- most of the time you
>can see nothing in particular.

I got one from Nashbar a couple days ago ($6.95).  I've used it for
a couple of hours and don't intend to use it any more.  What a pain.
You have to re-aim the mirror by turning your head to just the right
angle each time you want a view of what's behind you.


-- 
Richard Foulk		richard@pegasus.com
Newsgroups: rec.bicycles.tech
From: fike@chezp.enet.dec.com 
Subject: Re: Trailer with infant and toddler
Organization: Digital Equipment Corporation
Date: Wed, 11 Nov 1992 15:56:18 GMT


In article <1992Nov11.134521.12093@waikato.ac.nz>, waldrond@waikato.ac.nz writes...
>Has anyone successfully hauled 2 children in a Burley trailer when the
>younger one is only 3 months old?   We have a 3 month old and a 2 year old
>and I'm looking for a way to put them in there, so that they'll both
>be comfortable. When we had only one 3 month old, we just put her in the
>car safety seat and strapped the car safety seat inside the trailer. 
>There isn't enough room for the car safety seat and the 2 year old in the
>trailer. The 3 month old can't sit up by herself, so she needs some
>support.  What's the solution?
> 
>Thanks,
>Dan
>waldrond@ruakura.cri.nz


	Leave her with a sitter. Seriously, there's little or no suspension
or shock absorbing capability in a trailer and a baby that young doesn't have
the muscle needed to hold their head/neck properly to absorb minor road impact,
so unless you're talking about a slooowwww easy ride around the block, Leave
the child home until she's at least toddling age (1yr +). A mind is a terrible
thing to waste (or knock the hell out of!).

Newsgroups: rec.bicycles.tech
From: tan@lynx.msc.cornell.edu.UUCP (David Tan,Box 219 Baker Lab,54810,2720402)
Subject: Re:  Suspension on *road* bikes
Originator: tan@msc2.msc.cornell.edu
Organization: Cornell-Materials-Science-Center
Date: Thu, 5 Nov 1992 16:35:03 GMT

From article <Bx85GL.E7K@news.iastate.edu>, by twjm8@isuvax.iastate.edu:
> 
> Also, how do the suspended stems provide damping? 

I think the Girvin uses elastomer bumpers, don't know about the Allsop stem.
The [inelastic] material and design of the Allsop beam are chosen to provide
springing and damping.

[stuff about spring oscillations]
> 
> These oscillations occur if the rider provides no damping.  You forget that
> most of the damping (suspension or no suspension) comes from the rider.

This may be true, but if the suspension has more than trivial travel (such
as fork or chainstay flex in a non-suspended bike) the rider has to work
quite hard to damp out (dissipate the energy from) the oscillations, hence
the statement that these oscillations are bad for bike control, and hence
the prevalence of extremely inelastic materials and designs (squishy bumpers,
air/oil shocks, etc) in suspension systems to do as much of the work as
possible for the rider.
 
>
[ ... ]
> 
> One other point.  About the comment on the suspension distributing the shock
> over a longer period of time.  I was not talking about a long period of time
> (i.e. 30 seconds) but a change from, say, 0.1 seconds to 0.5 seconds. If one
> uses a simple rectangular approximation to calculate the energy due to the
> impact (by integrating the power over time ), one can see that the maximum
> power coming from an impact of 0.5 seconds is much less than an impact of the
> same energy with a duration of 0.1 seconds (5 times less).   That would result
> in a great reduction of fatigue if many bumps such as this were encountered on
> a ride. 
> 
> This example is, of course, contrived.  But the basic principles are true.  The

Point taken, but I don't know how great this effect is.  Certainly this would
be the principal (read "only") effect in an undamped oscillator, but most 
suspension systems try to dissipate the energy before the spring can give it
back (in however distributed a fashion.)  I realize that some of the initial
impact will be transmitted to the rider, and you're right about the reduced
power, but remember that much of the energy from the shock (not absorbed by 
the tires, anyway) will be stored in the spring, and it has to go somewhere.

> reason it takes less effort to absorb a bump over a longer period of time  is
> that the muscles are inherently nonlinear; try bench pressing 100 lbs 10 times
> then try pressing 200 lbs 5 times.  I guarantee the 100 x 10 set will be much
> easier.
> 
Agreed.

> I hope this clears a few things up.  Otherwise, you'll just have to come to
> Penn State and study acoustics and vibration with me.
> 
> Dave


Dave
From: cs92mjd@cen.ex.ac.uk (M.J.Davis)
Newsgroups: rec.bicycles.tech
Subject: Re: Suspension on *road* bikes
Date: 6 Nov 92 16:32:32 GMT
Organization: Computer Unit. - University of Exeter. UK

In article <1992Nov5.163503.19538@msc.cornell.edu> tan@lynx.msc.cornell.edu.UUCP (David Tan,Box 219 Baker Lab,54810,2720402) writes:

>   I think the Girvin uses elastomer bumpers, don't know about the Allsop stem.
>   The [inelastic] material and design of the Allsop beam are chosen to provide
>   springing and damping.

The Girvin uses an elastomer bumper. Damping comes mainly from friction in the
pivot, although there's a _tiny_ bit from the hysteresis of the bumper. The
Allsop stem uses a simple steel coil spring. All the damping comes from 
friction in the pivots. Plus which it's ugly as hell :-)

Mike.
From: jbrandt@hplred.HPL.HP.COM (Jobst Brandt)
Date: Thu, 12 Nov 1992 21:08:08 GMT
Subject: Re: Winter riding -- garnet tires?
Organization: Hewlett-Packard Laboratories, Palo Alto, CA
Newsgroups: rec.bicycles.tech

Joshua Putnam writes:

> My current idea is to put garnet or Carborundum grit onto a
> moderately-wide slick, say an Avocet Road, using something like Le
> Tour's "New Tread" compound.

Sounds good but I don't believe you can easily make anything adhere to
the tread of your tire to the extent that it won't peel off in use,
especially in wet and cold.  The best approach would be to have the
grit embedded in the vulcanized tread because it won't clog up there.
Rubber has sufficient frictional losses so that it remains thawed in
all but the coldest conditions.  When the tire is no longer thawed,
ice and snow are cold enough to give better traction anyway.  I have
had the opportunity to ride on many miles of frozen lakes and found
that only when it warmed up to near freezing did the ice become
unmanageably slippery.

jobst_brandt@hplabs.hp.com
Newsgroups: rec.bicycles.tech
From: IIRE@joyl.joensuu.fi (IIRE_ANTTI)
Subject: Re: chain skip in snow
Organization: University of Joensuu, Finland
Date: Tue, 10 Nov 1992 13:40:35 GMT
X-News-Reader: VMS NEWS 1.21

In <92Nov09.180229.23300@acs.ucalgary.ca> titus@calvin.phys.ucalgary.ca writes:

> Hi!  I have a Kuwahara Shasta which has, I believe, a hyperglide chain,
> and Shimano Deore (LX or DX I'm not sure) stuff on it.  I am fairly
> new to riding an MTB, and this last week, I had my first opportunity to 
> ride it in icy weather.  Today, however, I got to ride it in farily deep 
> snow.  Soon after snow started getting into the workings of the bike (i.e. 
> the rear derailleur, the front derailleur, the brakes, my boots  (:= )
> the chain started to skip really badly, i.e. on every pedalling cycle it must
> have skipped 3 or 4 times.  As you can imagine, this was not fun.
> 
> My question is:  is this to be expected when riding in snow, or is it as I
> suspect that my bike needs some adjustments?
> 
> Thanks in advance!
> 
I'm afraid that you'll have to expect this to happen all the time
when riding in snow. Especially, when the snow is "warm" (=temperature
is somewhere around 0 degrees Celsius) (I don't know your F:s), it
is sticky, naturally. 

I have been riding in snow for many winters now (actually this is the
first with mtb), and I have learned to deal with the snow. Usually, when
it gets to your rear cogs, the chain will slip couple of times. But after
a second the chain will remove the snow from teeth and chain will stop
slipping.  I must emphasize, that this happens only when chain comes to
cog, which have not been in use for some time. If you use the same
cog for longer time, snow doesn't have the time to hide teeth under it,
because chain "wears" the snow out all the time. Got it?

So my advice is, especially when off road: choose the gear, what you 
expect to be the most needed, in advance, and use it! Avoid changing. 
Now you can't go very fast, but that is impossible anyway if there is 
lot of snow.

Happy riding!

Antti Iire, Univ. of Joensuu, Finland       iire@joyl.joensuu.fi
From: gustilo@pop-server.upenn.edu
Newsgroups: rec.bicycles.tech
Subject: Comments Wanted: Brake Lever Extensions
Date: 6 Nov 92 04:35:32 GMT
Followup-To: rec.bicycles.tech
Organization: University of Pennsylvania

greetings,

I am thinking of getting these thingies and would like to hear comments as
to their general usefulness and which ones work the best.

thanks in advance


Standard Disclaimer:
  I am not responsible for comments that I make after 3:00 AM or after five
cups of coffee, whichever comes first.
Newsgroups: rec.bicycles.tech
From: titus@calvin.phys.ucalgary.ca (Titus Mathews)
Subject: chain skip in snow
Date: Mon, 09 Nov 92 18:02:29 GMT
Organization: Institute for Space Research

Hi!  I have a Kuwahara Shasta which has, I believe, a hyperglide chain,
and Shimano Deore (LX or DX I'm not sure) stuff on it.  I am fairly
new to riding an MTB, and this last week, I had my first opportunity to 
ride it in icy weather.  Today, however, I got to ride it in farily deep 
snow.  Soon after snow started getting into the workings of the bike (i.e. 
the rear derailleur, the front derailleur, the brakes, my boots  (:= )
the chain started to skip really badly, i.e. on every pedalling cycle it must
have skipped 3 or 4 times.  As you can imagine, this was not fun.

My question is:  is this to be expected when riding in snow, or is it as I
suspect that my bike needs some adjustments?

Thanks in advance!


T. =8)
From: mjs@fc.hp.com (Marc Sabatella)
Newsgroups: rec.bicycles.tech
Subject: Re: Self-Healing Tube Progress Report
Date: 5 Nov 92 18:04:46 GMT
Article-I.D.: fc.Bx98w0.4s0
Reply-To: marc@hpmonk.fc.hp.com
Organization: Hewlett-Packard Company
X-Newsreader: TIN [version 1.1.4 PL6]

[ regarding an ordinary tube ]

Wayne Iba (iba@kronos.arc.nasa.gov) wrote:
: Anyway, I pulled out the thorn and heard the
: distinctive hiss and started mentally gearing up for fixing the flat.
: To my astonishment (actually unbelief) the hiss stopped.

Yes, once the air pressure is reduced, it may start coming out more slowly.
Sometime a good strategy is to put the thorn back *in*, which often plugs the
hole nicely.

: it was flat the next morning.

In theory, the self-healing tube would not have been flat even by the next day,
so you haven't convinced me these slime tubes wouldn't be worth it *if* they
actually worked.

--
Amendment 2 - Shame On You, Colorado
--
Marc Sabatella
marc@hpmonk.fc.hp.com
--
a disgusted resident of the first state in history of the union
to enact a constitutional amendment that explicitly legalizes discrimination
against a particular minority
--
All opinions expressed herein are my personal ones
and do not necessarily reflect those of HP or anyone else.
Newsgroups: rec.bicycles.tech
From: shenry@cs.rice.edu (Sam Henry)
Subject: Re: Trailer with infant and toddler
Followup-To: rec.bicycles.misc
Organization: Rice University, Houston
Date: Wed, 11 Nov 1992 16:46:54 GMT

In article <1992Nov11.134521.12093@waikato.ac.nz>
waldrond@waikato.ac.nz is trying to get mobile: 

>Has anyone successfully hauled 2 children in a Burley trailer when the
>younger one is only 3 months old?  ...
>There isn't enough room for the car safety seat and the 2 year old in the
>trailer. The 3 month old can't sit up by herself, so she needs some
>support.  What's the solution?


You may be stuck for another 3 or 4 months.  I wouldn't try this
without the car-seat until the child is definitely stable sitting up
unsupported.  

Alternatively, you might trade the Burley for a Winchester.  They have
very similar designs, but the seating arrangement will more readily
accomodate what you want to do.  The seats are separate and face in
opposite directions.  The harness strap will hold the car-seat in one
trailer-seat, leaving the other entirely unencumbered for the older
child. 

-- 
sam henry <shenry@rice.edu>
Wanna ride?
Newsgroups: rec.bicycles.tech
From: shenry@cs.rice.edu (Sam Henry)
Subject: Re: Gear racks for MTB?
Followup-To: rec.bicycles.marketplace
Organization: Rice University, Houston
Date: Mon, 9 Nov 1992 16:41:19 GMT

In article <1992Nov8.233015.5490@cs.su.oz.au> jimu@orthanc.cs.su.oz.au (James Uther) writes:
>
>I'm looking around for a rear panier rack for my mtb. ... Blackburn
>seems to be the best bet, probably the rack1. Anyone had bad/good
>experiance with this rack? 


I have this on a touring bike and really like it.  I think the next
alternative is a Bruce Gordon mega-buck rack.

By the way, I have moved the followup to rec.bicycles.marketplace.

-- 
sam henry <shenry@rice.edu>
Wanna ride?
Newsgroups: rec.bicycles.tech
From: sjc@borland.com (Steve Correll)
Subject: Summary: rebuilding Look pedals
Originator: sjc@genghis.borland.com
Organization: Borland International
Date: Tue, 10 Nov 1992 18:20:36 GMT

Recently I asked how to disassemble a Look pedal to repack the bearings, and
promised to post a summary. I received no answers except the useful suggestion
that if one shoves enough fresh grease in, the dirty old grease must come out.
I guess that's what I'll do.

Serves me right--if I would replace my old pedals with the latest and greatest
new ones every 9 months like I'm supposed to (Time, Sampson, Shimano SPD, etc),
then I wouldn't have these problems. :-)
Newsgroups: rec.bicycles.tech
From: tomk@netcom.com (Thomas H. Kunich)
Subject: Re: Spoke lub defies laws of physics
Organization: Netcom - Online Communication Services (408 241-9760 guest)
Date: Sat, 14 Nov 1992 02:14:55 GMT

In article <1460011@hplredHPL.HP.COM> jbrandt@hplredHPL.HP.COM (Jobst Brandt) writes:

>About BB cups unscrewing... That's called precession and, if the
>exercise doesn't embarrass you (as it did some who read this
>previously), you can demonstrate it by making a circle with one thumb
>and fore finger while rolling your other index finger around in the
>opening as if it were planetary gear.  The roll will precess in the
>opposite direction from the contact point.  This is also the effect
>that unscrews pedals if not threaded R-R and L-L.  I find it amazing
>that only Swiss and English BB's are properly threaded.  I have always
>used "English" threads for that reason.
>
I agree with this statement. However, I have found that I can't live
without an Italian racing bike and a French racing bike and as we
know, they both use right hand threads.

If your bottom bracket is right hand threaded and the fixed cup comes
loose for any reason it will work it's way out and dump the bearings on
the road. So if you _must_ have Italian or French threads, be sure and use
bearing retainers for the balls.

English threads will also loosen slightly but they will just 'click' at 
you and become annoying until you tighten them up.

Newsgroups: rec.bicycles.tech
From: lavalj@rs6308.ecs.rpi.edu (Jean-Etienne Lavallee)
Subject: Re: Flexstems and suspension
Keywords: 
	I have friend that used the Girvin flexstem with an air/oil shock and 
Reply-To: lavalj@rpi.edu
Organization: Rensselaer Polytechnic Institute, Troy, NY.
Date: Sun, 8 Nov 1992 22:01:38 GMT

wouldn't stop raving about how much he liked it. I think he was using either a 
Trek DS2 or an old RockShox. From what he told me the trick was to adjust his
shocks so that they wern't reacting to every single bump, only the big ones.
The way things worked out, the stem wold take out the little bumps like small
stones and ruts and the combination of the shock and stem would suck up the rough
hits like roots and big rocks. I tried it out once and have a warning. If you
aren't used to the tilt, wiggle of shocks don't go crazy on your first ride with
such a combination since the slight wiggle in the stem tends to amplify the 
effect when attacking tight turns. Other than that I did notice the effect of the
stem and it wasn't all that bad to get used to. 
	I've also seen the combination of this stem/shock idea with Allsop's 
Frankenstem. IMO, any "suspension" stem alone only absorbs the shock felt by 
the rider and doesn't really improve the traction of the bike.(sorry, Team
Richey) But the combining of suspension stems and forks is still a niffty idea
and worth using if you've got the bucks.
					- Jean-Etienne

-- 
lavalj@rpi.edu     | "I'm an unlimited creature in a limited world."
                   |                       - Leveticus
		   | "The glass is neither half empty or half full,
		   |    it contains a liquid and a gas each of 
		   |    which have a volume that is 50% of the
		   |    volume of the glass. So there."
Newsgroups: rec.bicycles.tech
From: shenry@cs.rice.edu (Sam Henry)
Subject: Re: Bar-end Shifters
Organization: Rice University, Houston
Date: Thu, 12 Nov 1992 16:39:25 GMT

In article <1992Nov12.145220.27198@athena.mit.edu>
aviator@athena.mit.edu (Joakim Karlsson) writes: 

>... I'm thinking of buying a Specialized Allez road bike and having
>it assembled with bar-end shifters ... with Shimano RX100
>components.

>I'd like to hear any comments regarding the advantages and disadvantages
>of doing this.  The down tube just doesn't seem like the right place
>for shifters.  

Well, it has been the place for years until just recently.
I have bar-end shifters with SunTour components and they work fine.
Except that I am not particularly enamored that it takes moving two
hands out of the steering position to change gears.  The cable run is
long and until the stretch works out of new cables, it is sometimes
sluggish and requires frequent adjusting.  But that would hold true
for any shifting system on the handlebars.

>... Will they work good (or at all?) on a bike with RX100 components?
>The bicycle dealer says yes, and that they'll install them free of
>charge, except for the difference in cost between the parts.

They should.  If the shifters and drive train are compatible, then I
see no obsticale.

If he is willing to do freebies, how about SunTour Radius or Edge
drivetrain parts and SunTour Command Shifters.  Similar to bar-ends,
but they sit up by the brake-hoods.  More obtrusive than Campy's Ergo
or Shitmano's STI (which is avaiable at the 105 level this year).
More convenient than bar-ends.  They've workded a lot of the bugs out
and it is an option I am considering in place of my bar-ends.

-- 
sam henry <shenry@rice.edu>
Wanna ride?
Newsgroups: rec.bicycles.tech
From: mack@oakhill.sps.mot.com (Gregg Mack ( Sun ))
Subject: Re: Environmentally responsible frame painting
Organization: Motorola Inc., Austin, Texas
Distribution: na
Date: Tue, 10 Nov 1992 22:59:00 GMT

ajackson@ernie.Princeton.EDU (Andrew William Jackson) writes:

>Chemical strippers from the hardware store are ok since they kind of dry
>up and form a thick gooey paste.  Just wrap it all up with some newspapers
>and paper towels, stick it in a plastic bag, and throw it out the window
>of your car on the highway.

Please make sure that this is done ONLY while driving over a bridge that
crosses a stream! :-(

-- 
Gregg Mack    512-891-8704  ---------- __o       __o       __o       __o
gmack@paceline.sps.mot.com  -------- _`\<,_    _`\<,_    _`\<,_    _`\<,_
Motorola RISC uProcessors   ------- (*)/ (*)  (*)/ (*)  (*)/ (*)  (*)/ (*)
Austin, Texas  USA          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
From: truesdel@ics.uci.edu (R. Scott Truesdell)
Subject: Re: Symmetric rear hub
Newsgroups: rec.bicycles.tech
Organization: University of California, Irvine
Date: 13 Nov 92 22:09:03 GMT
Followup-To: rec.bicycles.tech

Back to the original question...

The hand built Manitou mountain bikes have assymetrical rear triangles to
accomodate dishless rear wheels. The dropouts are offet to the right
otherwise the rear wheel wouldn't be in line with the frame and front
wheel.

The special wide hubs are built by Manitou. I think the axle spacing is
150mm or so. Doug also makes a custom front hub as well (around 120mm?).
All in the interest of lateral strength. The wider hub flange spacing is
effective at increasing the lateral spoke angle for all spoking patterns,
unlike increased flange diameter which approaches zero increase in lateral
spoke angle as the spoke pattern approaches tangental.

The Manitous are legandary machines but you are stuck with one and only one
source for hubs. Not that the lucky owners complain...

  --scott
Newsgroups: rec.bicycles.tech