From: sgg5e@galen.med.Virginia.EDU (Stephen G. Graber)
Subject: Re: Questions on Sew-ups
Organization: University of Virginia
Date: Wed, 29 Jul 1992 16:44:13 GMT

>I am looking for more in the way of tips on
>how to get the best performance from the tire/rim combination. Any information
>will be greatly appreciated, my knees will also thank you. 

Thought I'd toss my 2 cents worth your way as well!  I've been hooked
on tubulars for years,IMHO there biggest advantage is by way of
comfort- they have more ability to deform (since they don't bulge out
into the sides of the rim) than clinchers and hence really soften the
road by comparison.  In terms of rolling resistance they may not
perform any better than good clinchers unless you buy good tubulars
and glue them on carefully.  In that regard I've found that the better
tubulars are worth the extra $ in terms of longevity and performance.
I use the Vittoria CG and CX tires- they last 2-3 times longer than
the cheaper ones, ie. Vittoria Mondiales, Wolber NeoPro SP1s etc.  I
haven't used any Continentals but have heard good things about them.
I had one set of Wolber Criterium Setas- marvelous.  Now I stick to a
CX on the front and either a CG Pave (training) or CG (performing!) on
the rear.  Since switching to these "good" tires flats have ceased to
be a problem and they seem to last 5000+ miles.

Gluing is the down side though not as bad as trying to patch the damn
things!  All the available cements seem to work well, I used to use
Wolber but now use 3M "Fast-Tack" (available at automotive stores,
intended for gluing carpeting to metal).  It holds better than the
cements, cleans off the rim more easily and dries faster.  I disagree
with the poster on the net who said he learned not to glue his tires
"too tightly".  If you roll your tire off the rim in a hard corner
you're going down and will probably hurt yourself and others.  It is
hard to remove a well glued tire but not impossible.  If you use
quality tires and inspect them frequently flats shouldn't lose too
many races for you.

I like to stretch a new tire on a rim before gluing- actually I try to
buy my tires 6-12 months ahead and leave them on old rims (not glued
and not inflated).  This allows the latex sidewall coatings to cure
and toughen.  I inflate the tire 24 hrs before I glue it so its well
stretched out.  I score a new rim before gluing, put a moderate coat
of Fast-Tack on the rim and a thin coat on the tire.  I don't let them
set up for more than 5-10 minutes.  BTW, an old toothbrush is a great
way to spread the glue around.  To get the tire on the rim I use my
bare feet!  Start with the valve, being sure its in straight, then
work your way around on both sides of the valve so that when the final
pull comes, you'll be pulling on the tire directly opposite the valve.
When doing the final pull, I hook my toes around the rim to hold it on
the ground and by pulling hard on the tire you can "drop" it onto the
rim without too much mess.  I'd advise practicing putting a tubular
without any glue onto your rims a few times before you go for it.
As soon as the tires on the rim I inflate it to 80-100 psi, rotate it
slowly to see how its centered- it usually doesn't need any
adjustment- and then I roll it around on a cement floor by pushing
down hard on the axle ends.  This helps seat the tire, and if you hold
the thing straight, helps perfect the tires alignment.  If its grossly
out of alignment you should see it by watching the center bead as you
slowly rotate the wheel.  Then I leave the tire inflated overnight
before putting it on the bike.  I deflate my tubulars after every ride.

Good luck!  I'll bet you'll be riding tubulars exclusively before long!

-Steve

--
Stephen G. Graber                  sgg5e@Virginia.EDU
Department of Pharmacology         
University of Virginia             work: (804) 924-9977
Charlottesville, VA 22908          home  (804) 973-1283
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