|Can anyone recommend sew-up tire?||skippy pinfish|
Nov 28, 2002 4:59 PM
|I dont know anything about sew-ups, are they more durable than a a racing clincher or are they as fragile. Any info would be appreciated. Thanks Skippy|
|no more durable...||C-40|
Nov 29, 2002 6:18 AM
|A good sew-up would have pretty much the same construction as a good clincher. A latex tube (that leaks air quickly) would be generally be used. The total weight of a clincher with a latex tube and a tubular will be very close to the same.
The only thing that is more durable about a tubular is their resistance to pinch flats, which is a function of the shape of the rim and has nothing to do with the tire.
|re: Can anyone recommend sew-up tire?||JimP|
Dec 3, 2002 8:10 AM
|C-40 has stated some of the similarities and differences. There is a difference in the maximum air pressure for the top line tires. A Continental Comp or Sprinter tire is rated up to 170 psi where some of the track tubulars can hold over 200 psi. I ride on Sprinters that I inflate to about 125 psi since I weigh about 190 lbs. Most racing clinchers would be inflated at their max at that pressure and would risk pinch flats if less than that. The biggest difference in weight between the clinchers and tubulars is in the rim. A tubular doesn't need the "hook" or flange on the rim to hold the tire on and can be much lighter. I still have a 15 year old tubular rim that weighs 295 grams and some of the newer rims are lighter than that.
Dec 3, 2002 6:31 PM
|For a given weight the sew-up will be the stronger tire. Figure a really light clincher will weigh 190 grams or so, plus tube at 60grams or so and rim tape as 20-30grams, but the 190 gram tire is paper thin and generally has no additional puncture resistance such as a kevlar or nylon strip in the casing. A good tubular like a Corsa CX weighs about 250-260 and contains a kevlar strip for puncture resistance...
Just as the tire has to have a bead for proper seating, the clincher rim also needs a bead, which if you imagine is a cantilevered beam sticking out from the rim being eternally bent outward under tire inflation pressure. These rims are heavier and more subject to damage under impact, just as clincher tires are subject to pinch flatting.
The other reason for tubulars is that their round shape provides more consistent contact patch as the tire rolls over giving more consistent handling, and with good supple tires, will actually give greater cornering grip due to this. When raining or on rougher roads, the reason most pros ride tubulars is that they run with low rolling resistance at low pressures where the tire has the most grip and do not risk pinch flatting, so in a rainy crit you may only run 90-100psi to get the maximum grip without worrying about rim or tire damage.
Look at Dugast, Veloflex, or Vittoria for the most supple tires (Clements were sweet in their day as well) Continental makes slightly more durable, but stiffer casing tires which are nice as well.