Conference noted::bicycle

    
    If he "pops 15 spokes a year" then his wheels are built wrong. That's
    the only explanation. How well the wheel is built is what determines
    the strength of the wheel, much moreso than the components.
    
    Steel rims have almost disappeared on bikes sporting caliper brakes,
    because they don't stop worth a &^&% when wet or greasy. Alloy rims
    don't have this problem.
    
    Your friend needs to get a decent set of wheels built for his bike.
    If he still pops spokes then a heavier duty wheel is in order, such
    as a 40 spoke.
    
    CdH
    

    This is undoubtedly an oversimplification but wheels that are built
    properly do not break spokes.
    
    If someone breaks a lot of spokes it is usually because the wheels
    were not tensioned right in the first place, though some other factors
    like age and stress can enter the picture.  My rule of thumb is
    that if a wheel has broken a few (3 or 4) spokes, it's time to rebuild
    the wheel, chuck all the old spkes and rebuild.  That has worked
    well.
    
    You can significantly weaken your spokes by shifting the chain into
    the rear wheel, then the [usually] 9 spokes affected will be more
    likely to break.
    
    As for the type of rim (aluminum alloy vs steel), steel might be preferred
    by someone who broke lots of spokes because it will be less out
    of true when a spoke is missing than would an alloy rim just because
    it is more rigid.  It would also be more easier to build a wheel
    with a steel rim without getting the tensions close to even -- and
    therefore break more spokes.
    
    Ask him (?) who builds his wheels.
    
    I haven't used a steel rim in years.
    
    ed

    RE: .2
    
    Steel wheels are NOT more rigid than aluminum alloy wheels; they're
    more elastic.  They absorb shock (by denting) rather than transferring
    it to an opposing spoke, so that if the wheel is improperly built,
    they're less likely to pop a spoke on a sudden impact.
    
    When I used to race motocross, I saw this happen dozens of times.
    (Ever tried hitting a series of 2' high bumps at 40 mph, or jumping
    50' on your bike?  The impact in those cases is an order of magnitude 
    greater than what a bicycle sustains.)
    
    But guess what kind of wheels motocrossers use today?  Aluminum.
    When properly built, they're superior in every way.  They're an
    even bigger advantage on bicycles, with their caliper brakes.
    
    GP4s forever,
    
    MATT

    always did have trouble with those metallurgical terms.
    
    what I meant was that, when missing a spoke a steel rim will
    appear to have suffered less damage (be less out of true) than
    an aluminum rim. And then (because of its greater elasticity?) any
    warps will be easier to remove than would misshapenness in an
    aluminum rim, and therefore the life of the rim might be longer.
    
    But, I think we all agree, a well built, good aluminum rim is the best.

    If your friend went with ultra-light aluminum rims that could also
    be the reason for a problem.
    
    ed

How tight should spokes be? How do you wheel builders set the tension?

bob

    I have to agree with all that has been said about alloy rims, spokes,
    etc. I have used alloy rims for years, and have only had problems
    when I allow broken spokes to go unattended too long. Alloy rims
    don't "tolerate" broken spokes as well; I've actually had chain
    reactions develop where massive numbers of spokes have EXPLODED
    do to the wheel "system's" inability to distribute forces evenly.
    
    Sounds alot like popcorn. Fun to watch---a pain in the glutius
    when it happens to you, however!
    
    I'm curious---from a tensile strength standpoint, how do steel
    and aluminum alloy spokes compare??
    
    John E.
    

Re .5 "How tight should spokes be."    
    
    The spokes should be as tight as possible.  The limiting factor
    isn't usually the strength of the spoke, but the strength of the rim.
    
    You say, "But wait, how do spokes get broken?"
    
    The answer is that it is the loose spokes that break due to fatigue.
    On a wheel where the spokes are at full tension, the spokes do little
    bending, and little breaking.
    
    In Jobst Brandt's book The_Bicycle_Wheel, he recommends the following
    method for bringing wheels up to tension:  go around the rim,
    tightening each spoke one half turn.  After each pass around the
    wheel, squeeze together groups of four spokes, so that they seat
    and so that residual stresses are taken out.  After one of the
    squeezes, the rim will start to fail.  It gets a wavy sort of shape,
    kind of like a Pringle's potato chip  (or in cylindrical coordinates,
    z = k * sine ( 2 theta) ).  At this point go around and loosen all
    of the spokes by a half turn, and true away the wave.
    
    I have used this method on 2 wheels so far, and thay have worked
    wonderfully.  There have been no broken spokes, and in the last
    thousand miles of beeing riden by an eighth ton biker, there has
    been very little change in trueness.                    
    
    -Jeff Bell

    re .5	Try the F# above middle C.
    
    	Reg
    

    
    I tend to tension wheels depending on the use. For an everyday bike,
    I like to make them pretty tight but not to the max. This makes
    the wheel ride more comfortably. For racing or loaded touring wheels
    I tend to crank them almost right to the max, but not all the way.
    This is where I disagree with Brandt, I don't think you should EVER
    tension a wheel such as to make it deform. Make sense?
    
    I've never seen aluminum alloy spokes, and I hope you haven't either.
    They sure wouldn't hold up well. Alloy nipples are supposedly the
    hot thing for time trial wheels, but I never use them. It's just
    not a good place to save weight. Consider the forces on the threads
    of the nipple. Think about it... a steel spoke running in aluminum
    threads... not a great idea. High quality brass nipples like DT
    or Alpina may add a couple ounces to the wheel but at least it'll
    stay together.
    
    CdH
    

    OK, alloy rims are the way to go, and one big reason for this is their
    superior braking.
    Now, I'm considering upgrading my old Schwinn (wheels, gears and shifters).
    I've seen built wheels in Performance and Nashbar.  Performance's cheapest
    use a (Wolber?) "silver finish" rim.  This sounds like an alloy trying to
    look like a steel.  Would this be slippery?
    Also, any comments on buying catalog-shop-built wheels?

     
    "Silver finish" usually refers to the wheel being silver in color
    (as opposed to gray,black,etc.) but the wheel is still alloy and
    therefore retains its superior braking capabilities.
    
    J. Bush
    

    
    I bought a pair of built rims from Nashbar.(Wolber as a matter of
    fact) I road them cross country 2 years ago and they're still going
    strong!
    
    Stew
    

    Last time I flattened my touring wheels, I had them rebuild on Wolber
    rimes.  They seem to build up true and stay true.  My only objection is
    the finish: highly polished.  I guess that's what they mean by
    "silver".  I prefer the satin look.  But I wanted a 40 hole rim, and
    there are not too many about.

    
    Alloy rims are either polished or anodized. Polished rims are bright
    for a while but take polishing (what else) to stay that way. Rims
    can also be anodized clear, which gives the "satin" finish, black,
    or any number of colors depending on the anode used in the process.
    Anodized rims will scratch but they resist pitting and staining
    unlike polished rims, that's why anodized rims are more popular.
    
    CdH
    
    

I got a rim question.  I just bought a new bike, a Trek 520, which has
Matrix Titan Tour rims, 36 spoke, anodized alloy.

Wnen braking, there is a noticeable (sound and feel) pulsation as the "weld" 
(is thats what it is) in the rim passes through the brake pads.  The weld, 
while fairly smooth, isn't EXACTLY smooth and obviously the small mismatch in 
the butting edges is causing a little 'blip' in the braking.  

I'm concerned that this small edge (actually edges, since I can feel it on
both sides of both rims) will scrape and wear away the brake pads prematurely.  
Its not a very large edge, just about enough to slightly catch a fingernail.

Is this too much of an edge?  I'm going to try to look at some other rims,
but I want to hear what the experts here have to say.

Love the bike though!

	thanks, Josh

    
    This is actually a feature (not a bug).  The importance of
    pedalling cadence is widely recognized, but "wheel cadence"
    has been largely ignored.  Cycle computers with wheel-mounted
    pick-ups do measure wheel cadence, but then convert that into 
    "ground speed" on the read-out.  The rim-knick you refer to
    lets you viscerally sense the actual wheel cadence (though
    only when braking), and thus puts you more in touch with the
    cycling experience.
    
    Hope this helps.
    
    -john

    Re last.
    
    That was wicked John.
    
    Chris
    

     ZEN cycling... I like it!
    
    
       Chip

    Yeah, it's a feature, but John's got it all sideways.  The idea is that
    if you squeeze really hard on your brackes and the first 84 inches of
    rim don't stop you, that little low frequency vibration will catch
    the brake pad and danged sure stop you.
    
    I used a pair of them for an emergency stop on Mt Washington.  'Course
    I needed therapy afterwards and my fastball will never be the same but
    now that The Sox have The Rocket, noone cares anyway.
    
    :-)
    
    ed

    Awright, you guys!  Depending on how knowledgeable the person that
    asked the question is, you could this poor guy telling all his friends
    how the rim mismatches and bad welds that are eating brakepads and
    causing that annoying noise are:
    
    A SPECIAL MANUFACTURERS FEATURE NOT AVAILABLE ON ALL BIKES!
    
    No, it isn't normal...  You should NOT be able to feel the weld go
    through the pads.  Take 'em back.  Have the shop check it out.  If you
    don't like the answer call MATRIX.

    I'm sure this topic has been covered here, but I can't find it.
    
    How do I clean brake pad rubber from my rims?  Lemon Pledge was
    recommended to me, but it didn't touch the stuff (smells nice though). 
    What can I use without harming the anodization?
    
    Jamie

     I think if you're getting rubber build-up on the rims you should
    switch to another pad. I've never have this problem.
    
     It's usually the anodizing that get rubbed off (mine Mavics are a
    nice shiney silver now). Sooner or later your's will be too.
    
     I'd try a solvent. Something strong (unless fanatically environmental)
    like lacquer thinner or even a little nail polish remover. It won't
    hurt the rim, but be careful of the tire.
    
     Good Luck... How much build-up is there? Discoloration or outright
    bumpy???
    
     Chip 

    re .-1
    
    Just a couple of streaks from panic stops (I assume).  It may even be
    left over from before I put on new pads.  I wrote a note in here
    somewhere about a brake chattering and squealing problem -- new pads
    took care of that.  I bought a bike that had been hanging out in the
    store for a year and I think the exposure to air and UVs had dried out
    the original pads.
    
    I'll try the thinner.  The pledge didn't take it off but I noticed this
    morning that my braking was much improved.
    
    Jamie

After riding in the rain, I get some build-up on the rims. Not to the point of
being bumpy, but quite dirty looking. I've used citrus de-greaser to clean it
off. Takes some elbow grease.
						-- Tom

    
    Stop at an auto supply stotre and ask for degreasers used by auto
    body shops for cleaning cars prior to painting.  One product is
    Dupont Prep-Sol; Acme makes a similar product but I don't recall
    the trade name.  The bad news is it only is available in gallon
    size. The good news is it is an excellent degreaser that will
    not harm paint, rubber, etc and has a million uses.  I use it
    to clean my "other" bike ( harley davidson ).

    I think I've bought Prep-sol or a similar degreaser by the pint.  A
    pint goes a long way, even if it's cars you're degreasing.  It does a
    good job on road glop.

 Naphtha (lighter fluid or similar cleaner) or acetone (model paints) will
 take off streaking caused by black Shimano brake pads.  And they are
 usually available in small quantities.