So a pound on a rotating part is the equivalent of having 3 pounds of a non-rotating part? Obviously this would help you while spinning... but once the tires are already up to speed, seems like that kinetic energy could help too. Does anybody race XC with heavier tires? I switched my Maxxis 2.35's out to some 2" tires, saved a pound and a half overall, but it feels so much more unstable like on rocks and turns. Obvioiusly the extra air would help, but they had much more traction, more stability, etc. I'm just wondering what most people thought a good trade-off was between light and stable. Seems like I would go faster if I had more confidence, but then again, I just lost a race due to a couple of really long boring slight uphill sections. I originally wanted the Maxxis High-Roller semi-slick, but they're 1,050 grams. I'm wondering if the single ply version of the same tire would be a good compromise, since they're only 655 grams. Or, even the Bling-Bling duals... they're 700 grams. Looks like I'd have at least 150 grams more on each tire... not sure if that's a big deal or not. Since I'm not high-caliber or anything, I'm guessing not.