Quote:
Originally Posted by nmrt
1) pre-stretching: should I pre-stretch the tires?
2) how long to pre-stretch the tires?
3) how many glue coats on the rim?
4) do I need to glue coat the tires as well?
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Keep in mind that when dealing with tight tires it's the tire that's tight. Carbon rims are generally similar in diameter, at least from one batch to another, because molds don't have a wide range of error. Tubular tires have a wider range of variability due to it being a tube that is cut and joined. A tight tubular is usually because of the tire. An extruded aluminum rim has a much wider range of tolerance (length of metal cut and joined), clincher tires have a very narrow range of variability (molded and wire beads are pretty precise), so generally a tight clincher is because of the rim.
1. Pre-stretch - as mentioned above Vittorias don't need pre-stretch. Neither do Bontragers. These are the only two brands I've used in the last 7 or 8 years. I did have some Contis before that (generally prefer the Vittorias) and I don't remember anything about mounting them other than I can never get them straight and Vittorias and Bontragers go on straight without effort. If it's me then I'm just unable to mount tubulars properly but I suspect that Contis (Sprinter, Competition) aren't made straight or their casing is such that they twist easily.
2. No pre-stretch necessary. My fastest glue job on a brand new tire was when I got a call that the Missus was being induced. It was a Thursday, I needed to replace a tire, and I had a race on Sunday (that I was promoting as well as racing so basically I had to be there; only if there was a serious problem with the Missus/baby would I call the race). I ran down into the basement, grabbed a random Vittoria tire (I had maybe 10-15 tires), a tube of glue, and proceeded to glue the tire. It took maybe 10 minutes tops. I'd previously removed the old tire, else it would have taken me much much longer. Somehow I managed to not get glue anywhere, I went to the hospital, and after a day and change no baby. He arrived next week, Sat AM (and yes I left that afternoon to do course prep and Sunday race promotion). Glue job was fine, tire straight, etc.
3. Rim - I usually do a very light coat as a primer, a second coat where I try to cover everything including the narrow bits around the spoke holes, and if I missed anything or I let it sit too long I do a third thin coat, primer thickness. The last coat is partially to introduce some solvent to the glue, esp if I let it sit a while and glue is too dry feeling. If glue is too dry then impossible to adjust tire.
4. Tire - Two coats, light primer kind of coat, then a slightly heavier one. I do a lighter coat again if the tire is too dry.
My take on mounting tubulars in a bit more detail:
http://sprinterdellacasa.blogspot.co...e-tubular.html