Ron wants to know: What is the proper way to stretch tubular tires? What method do you use to glue them? What do you think of tubular tape?
I’ve never been a fan of tubular tapes. They just don’t offer the same level of security that glue does. There are a few ways to glue tubular tires, but here is how we glued them at the Team Highroad Service Course:
I start by inflating the tubular to around 40 or 50 psi and then mounting it on a bare, unglued rim for stretching. Then I inflate it to about 60psi and leave it overnight. If I were stretching a road tubular I would inflate it to 130psi.
If you don’t have a rim without glue on it to stretch your tubular, just mount it up for five minutes and then remove it. You’ll get nearly all of the stretching done that you need without running the risk of the tire getting stuck to old glue on the rim.
While the tubular is being stretched I lay down the base layers of glue on the rim. Be sure to do this in a well ventilated area. I like to do 2-3 thin coats on a new rim with about an hour or two between coats to let them dry. You want to end up with a nice even coating of glue that completely covers the portion of the rim that the tire will adhere to. If your rim has double eyelets like this Mavic rim, you’ll want the transitions between the eyelets and the bare rim to smooth. Avoid getting glue into the spoke holes, glue in there won’t do anything to help keep the tire on the rim and will only make the wheel heavier.
After the tubular is done stretching, I start applying glue to the base tape. Some tires have coated base tapes while others do not. If your tire does have a coated base tape, two thin layers of glue are all you will need.
If the base tape is uncoated you need to slowly add coats of glue until the base tape is fully saturated. This usually takes 2-3 thin coats. Once that glue has a couple of hours to dry, apply one last thin layer of glue to the tire to prepare it for mounting.
Keep in mind that the goal is to have a layer of glue on the tire that can interface and bond with the glue applied to the rim. All the layers of glue on the tire and rim work together to bond the whole assembly together securely. Any patch of tire or rim that doesn’t have these base layers of glue are a potential place for the tubular to roll off of the rim. Cyclocross tubulars are especially susceptible to rolling, so be sure to take your time and do it right with ‘cross tires.
Now it is time to apply your final wet coat of glue to the rim. Apply a medium thick coat to the rim and let it dry just until the glue barely flashes over and gets tacky. While that is happening, pump up your tubular to about 30psi for ‘cross tires and 60psi for road tires. Now for the moment of truth.
Put a piece of cardboard on the floor and set the rim on the cardboard with the valve hole facing up. Install the tubular valve first while making sure that the tire is centered on the rim. Then aggressively take hold of the tire and stretch it outward and downward as you work the tire onto the rim. At the end you can just grab hold of the final section of tire with your strong hand and lift it up over the edge and drop it down centered on the rim.
Now visually inspect the installation to make sure that the tire is on straight. Spinning the wheel to check for misalignment helps. Because your wet coat of glue is still wet, you should be able to move the tire around a little to get everything aligned correctly. Then press everything into place by rolling the tire on the floor while being careful to not ruin your alignment.
If you got any glue on your rim that needs to be removed, naphtha solvent, a rag, and some elbow grease will do the job. Don’t forget to do this work in a well-ventilated area. Let the glue cure overnight and you are ready to race.
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