measure roll coef of tyre's

[ada@prorider.or]

if there was a instrument where you could measure roll coeff of tyre
on the road and track and easy to cary with yoy and measure on the surface where you have to ride would you buy such instrument?

i understand that lot people do not care ,just trying to figure out or it would be worth the trouble in making it
since i have done studys and calc on it and found a way of measure it easy
well easy has cost lot of head ace and other testing

[rnhood]

Since rolling resistance is less and less an issue as speed increases (total resistance is more and more dominated by wind friction) and, the difference in RR between race tires in general is very little, I don't think there would be much value in determining the exact figure in-situ. It would seem to me that whatever laboratory method employed by the tire manufactures produces a figure of merit that is adequate for making the decisions that race teams, or riders, need to make.

In other words, I don't think a portable contraption that can measure tire rolling resistance would sell very well, unless perhaps it is very inexpensive and very accurate.

On the other hand, I would think that a device that measures wheel distortion and aerodynamics (the complete wheel) under dynamic conditions would be of value. This would produce a number that makes it possible to compare different wheels. After all, it's the total wheel that makes the difference, not just the tire.

[ada@prorider.or]

[QUOTE=rnhood, I don't think there would be much value in determining the exact figure in-situ. [/QUOTE]
well if you say very liitle how much is liitle for you in watts???

[mflaherty37]

I for one would like to have such an instrument. There is some lab testing out there that shows a 14 watt difference for each wheel at 100lb load and 50kph with a between at EVO CX and a Conti4000 (Conti being slow). The new Conti4000S is a rebutal with a rolling resistance less than some tubulars.

[nm87710]

whatever laboratory method employed by the tire manufactures produces a figure of merit

Where be the manufacturer's Crr figures of merit????? ;)