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Tips for
Attaching Tubular Tires
by David Teall
Twenty years ago tubular tires were the unquestioned performance choice. Today
manufacturers have developed and effectively marketed a clincher tire for everyone, and
tubular, or sew-up tires, have been relegated to a small niche in the consumer market.
Woefully this is so. What has caused this diehard traditionalist to build clincher wheels
is the quality of todays low-cost tubular and the cost of todays quality
tubular. Youve probably heard one or more pneumatic purists curse about some lump,
hump, or bump in his tubular. I too have felt the thump. Even so, there is a certain feel
that one can only find astride a pair of good tubular tires. But lets put the pros
and cons aside. This exposition considers the art of attaching tubular tires on the rim.
Before you open that tube of rim cement, inspect the tires
base tape. The base tape is that strip of fabric that is bonded (I use this word, in
reference to cheap tubulars, loosely) to the tubular directly over the stitching. It
protects the stitching and the casing, and it is the surface where cement and rim to the
tire connect. A poorly bonded tubular base tape is as dangerous as an improperly fastened
tire. If you can peel at a base tape with your fingernail and separate it from the casing,
dont by it, not at any price. If youre stuck with such a lemon, you can either
remove the base tape completely and apply cement directly to the casingstitching and
all, or remove and re-cement the tape. If you choose the latter, use Fast Tack (more about this
stuff later).
The next step is to stretch the tubular
by fitting it on a CLEAN rim. If youve been cycling for twenty-some years, then you
have a collection of trashed Fiamme Red Labels on which to stretch your "green"
tubulars. But you must clean off those layers of old cement, otherwise youll have
crusty specks of it stuck to your new tubular, and thatll compromise the bond when
you go to permanently mount it. Start by fixing the valve stem in the rim stem hole. Fit
the tubular on the rim, working equally on each side of the stem. Stretching the final
quarter of the tubular over the rim will probably be tight. Sit down on a bench, hold the
rim with the tip of your toes on either side of the valve, and pull the rest of the
tubular over the rim. It might be too tight to stretch over the rim, in which case
youll need to pre-stretch the tubular. I saw Roger Young do this once to a 50-dollar
track tire. He hooked the inside with one foot and pulled up with both hands. Then he slid
the tire around about one quarter of its circumference and repeated this all the way
around. Then the tire was ready for the rim.
Once you have the tire stretched on the rim,
carefully align it. Make certain that the valve stem is straight and that the tread
pattern runs centered around the rim. Then inflate the tire to its recommended maximum.
Inspect for obvious defects. The bike shop is less likely to accept a return on a tubular
thats been glued. If you have the time, leave your new tire stretched and inflated
overnight. The ideal situation is to store your tubular stretched on a rim and slightly
inflated (30-40 psi) until its ready for use. Some say that slightly aged tubular
tires are best; theyre more supple. In the old days, wed buy a seasons
supply in advance and have them all stretched, ready, and waiting on old rims. Gary
Dauer,
after a roller race in his garage, once showed us what looked like a coat closet. There
were, however, no coats insidenothing but tubularsthe bare rims skewered by
the closet rod. It smelledlike tubularsa tubular humidor. Mark Tyson pulled a
Clement Strata 66 to his nose and inhaled slowly. He closed his eyes, hesitant to exhale.
He finally did again breathe, then he slowly opened his eyes and said, "Nice."
Now that your tubular is stretched
and ready, its time to give some attention to your wheel. If your rim is brand new,
youll need to remove any excess oil from the manufacturing process. Use what ever
solvent the manufacture of the glue you plan to use recommends for surface prep. If the
surface of the rim is smooth, I like to score it up with an awl. Some think Im crazy
for tatooing texture into the concave of a brand new rim. They believe that the glue will
adhere to a factory smooth surface just as well as my gnarled. But Skiver showed me this
trick back when he and I were getting wheels together for a season on the board track, and
Ive stuck with it since. In any event, whether you scar or go smooth, you must put
an initial coat of glue on a virgin rim.
Which glue to use? That all depends. If
youre just starting out, use a natural base product like Tubasti or Clement, or a
synthetic with similar properties like Panaracer. These products require more time to set,
but they will allow you time to properly adjust the fit of your tire before it
sets. You can also remove without damage and reuse a tire once it has been mounted. Some
natural base products, like Tubasti, require mixing. You must really shake, knead, shake,
knead, and shake a tube of Tubasti well, otherwise youll get runny clear stuff
coming out at first and snotty off-white stuff coming out at the end of the tube. The
longer the Tubasti tube sits, the longer youll have to mix it up. If youve
mixed it and it still comes out runny, stick a clean bamboo skewer inside the tube and
stir, pull that really viscous stuff up from the bottom and work it all in. Clement red
and Panaracer (if you can find em) do not require mixing. 3M Fast Tack Trim, a product
primarily used for attaching automotive trim fabric to painted or bare metal, is strong,
clear, and you can race on it in an hour, but you better line the tread up perfectly the
first time. And dont plan to remove that tire and reuse iteven as a spare.
To avoid contamination, you should use the same adhesive
throughout the life of your rim, so availability has to be a consideration. You can get
Fast Tack Trim at most
automotive superstores, but the availability of traditional rim cements seems to ebb and
flow. Talk to your bike shop manager about the availability of the rim cement he carries
or stock up.
The initial coat of cement must be
thin and even. If it pools up in the center of the rim, its too thick. With
practice, you can apply such a coat right out of the tube. Have a plastic sandwich bag
handy. If you add too much to a spot you can stick your finger in the corner of the bag
and smooth it out. You dont want to get this stuff anywhere other than the contact
surfaceespecially not on the braking surface of the rim. Once you have applied the
initial coat, let it dry, an hour if youre using Fast Tack, overnight youre
using a rim cement.
Now that the initial coat of
cement is on your rim, you can remove your tubular from its stretcher rim and apply a very
thin coat of cement to its base tape. Inflate the tire to 60 or so psi. The tire will tend
to curl inside out; this is good. Apply an extremely thin coat of cement on the base tape
slightly wider than the approximate width of the rim on which youll later mount the
tire, 22mm or so. Have another plastic bag or two handy in case you need to smooth it out.
Start on one side of the valve and work your way around. You can hold on to the valve stem
while applying the last stretch of cement to the base tape. Then set the curled up tire on
a peg somewhere out of the way to dry, again, overnight if youre using rim cement,
an hour for Fast Tack.
With the initial coats of cement set on
the rim and tire, its time for the final coat and the mounting of the tubular. This
coat should be applied to the rim slightly thicker that the initial coat. Experience will
best show you exactly how much. When you later stress the mounted tire and see globules of
cement squeeze out, youll know you put on too much. If you dont see any excess
cement, youll have to wonder whether youve used enough. Set the wheel down
somewhere it will lie without resting on the rim. I like to have a large coffee can handy
and set the hub inside the can so the wheel rests on its spokes. A bucket will do. Now
grab that tire off the peg and release the pressure until it just holds its shape. Hold
the rubber of the tire at the valve in one hand and the wheel by its hub in the other and
fit the stem in the valve-stem hole. Now it gets tricky. You have to be careful not to
touch the cemented surfaces nor allow the cemented surfaces to touch anything else. Fit
what you can of the tire on each side of the stem. Then sit down on a bench, stick your
feet in the wheel (barefoots best), grab hold of the rubber with each hand on
opposite sides of the wheel, and alternately fit each side of the tire with both hands.
Its going to be real hard to keep the cemented surfaces away from other surfaces
when you get toward the end, but if you have properly stretched the tubular, have a good
grip with your toes, and you firmly hold the tire by its rubber with both hands up and
away from the side of the rim, you can do it. Once you have the tire cemented on the
wheel, starting on either side of the stem, grab the casing by the rubber and lift if away
from the rim, twist it slightly back and forth, and set it back in place. Repeat this
every four or five inches all the way around. This step assures a proper bond and lets you
see where there is adequate cement.
Now you can align the tire tread. For this I like to use a wheel
stand. Inflate the tire to 50 or so psi. Then slowly spin the wheel while sighting along
the rolling tread. Grab the spot where any whoop-de-do occurs and straighten it out.
Quality tubular tires will have a base tape that is centered and parallel to the tread,
and you can use the distance between the base tape and the edge of the rim to align the
tire. If youre using Fast Tack youll have to align your tire with the base
tape and the rim because your tire is pretty much stuck on contact.
The final step is to stress the wheel. Take the wheel
out of the stand (be careful not to touch the edge of the rim where cement has slightly
run over or oozed out) and inflate to the recommended pressure. Then set the tire on the
floor and straddle over it with your feet shoulder length apart. Place both palms on the
rubber (again, watch out for cement), and balance as much of your weight over the tire as
you can manage for two or three seconds. Repeat this for every four or five inches around
the circumference of the wheel. Leave the tire fully inflated for 24 hours if youre
using rim cement or one hour if youre using Fast Tack. Now youre
ready to take that last corner at Scotch Ridge without touching your brakes, or unleash a
vicious attack going into turn three at O.O.I.P., or dive down the banking in turn two of
the new velodrome at full speed, or any other such rush-producing activity. And no Mike
Walden incarnate will ever roll your tires off with his bare, bear hands.
Authors note
If I sound adroit, it is because I stand on the shoulders of many. Ive already
mentioned wheelmen Tyson, Dauer, and Skiver, and cycling legends Roger Young and Mike
Walden, all of whom imparted some bit of knowledge to me. Here I would like to acknowledge
the author of the seminal DD article on cementing tubulars, Mark
Loudenslagel. I
read and reread Marks article over and again when I was a novice. It showed
me the basics, all of which I have tried to regurgitate above. Thanks Mark.
Next
12/28/09
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