From: dahls@fhydra.dnet.unit.no (Joern Yngve Dahl-Stamnes)
Subject: Re: Questions on Sew-ups
Reply-To: dahls@fhydra.dnet.unit.no (Joern Yngve Dahl-Stamnes)
Organization: University of Trondheim, NORWAY
Date: Wed, 29 Jul 92 12:30:08 EDT

Thus spoke the keyboard of mike@pyrdc.UUCP (Mike Whitman):
>I am about to get a set of wheels with sew-up rims on them. I have always 
>ridden clinchers and want to start using sew-ups on my bike for some events
>I compete in. Time Trials and Crit racing will be the major use for this
>wheelset. I have a question, how do you glue tubulars to the rim? I know
>the basics of spread glue on tire and rim, wait till sticky, apply tire to
>rim, straighten tire, inflate. 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. 

I've been using sew-ups on my road bike since I began biking 3 years ago,
and will not use anything else on my road bike.

When you get a new rim there is no glue on it, so the first thing you
should do is to put a layer of glue on the rim and let it dry well (2 to 3
days).

When you put a new tire on the rim, strech the tire to make it a bit
wider. New tires are a bit too small, and is difficult to get on the rim.
Then put some glue on the tire and some on the rim and wait for about an
hour. Now the glue are almost dry, it won't stick to your fingers. Put the
tire on the rim.

If you want to put an old tire (a tire that already have been glued on the
rim but taken off again later, see below) on the rim, then apply a small
amount of glue (less than when using a new tire), wait and put it on the
rim. Or you could just put the old tire on the rim without putting glue on
the rim nor the tire. If the glue on the tire are very old, then you could
add glue to the rim *after* you have put the old tire on the rim. Just
bend the tire from the rim and put a small drop of glue on the tire.

When I began to bike, I didn't know that the tires was glued to the rim. I
was told that it was very important that the tire was well glued to the
rim, othervise the tire could get off the rim when going fast in a corner.
So I glued it very good - too good.

I participate in many race, and if I got a flat in the race, I must able
to change the tire fast to avoid loosing too much time. First I have to
take of the old tire, which is the operation that take the most of the
time. If it is glued too well to the rim I really have to fight to get it
off. So I quickly learned that I should not use so much glue on new tires.
After all, there is already glue on the rim.

I only put small drops of glue on the tire and use my finger to apply it
out on the tire. I use more glue on new tires than on old one. One drop
between each spoke for new tires and one drop every second spoke on old
tires. And I do *not* use any glue on the tire opposite to the valve. The
tire will be a bit "looser" here, which make it easier to get it off
again.

Remember, always keep and used tire with glue as a spare one when out
riding. If you use a new one, it will take some time before the glue begin
to "work". Used tires can be put on the rim without any glue at all when
out riding (just remember to take it off again when you get home again).

Hope this help.

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* I went back to my mother,           * Joern Yngve Dahl-Stamnes           *
* I said, "I'm crazy ma, help me!"    * University of Trondheim            *
* She said, "I know how it feels son, * The Norwegian Institute of Tech.   *
* 'cause it runs in the family."      * Division of Physical Electronics   *
*       - The Who, Quadrophenia       * e-mail: dahls@fhydra.dnet.unit.no  *
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