Originally Posted by
tetonrider
i'm of the opinion that rotating weight, on a bike, makes no difference vs non-rotating weight. there eIS a difference, but it is so incredibly minor as to be inconsequential--for me. not all feel the same.
For me there's a substantial difference in rotating weight, although I can't prove it using numbers. Basically if I have heavier wheels I don't have the same jump and I burn a lot of matches doing my whole tail gunning thing. In 2010, at my peak fitness, I didn't finish any races with my heavier but pretty aero Jet 6/9 set up, and in fact I did better in the same Tues races with the non-aero Bastognes/Ardennes (same tires, same hubs, same spokes). With lighter wheels I can accelerate more quickly. The faster my start speed, the less important rotating weight is, so starting a sprint at 35 mph means I'd want an aero wheel set, starting at 25 mph means a light one. From 25 mph my whole jump is used to get me up to speed. I haven't started a sprint at 35 mph in forever but if I started at that, then applied the jump and stuff, I think I'd be going a bit faster and therefore aero becomes significant. Nowadays it seems that my start speeds are lower therefore rotating weight is more important.
At some point I want to do some experiments regarding rotating weight or have someone who knows math/physics + cycling do some number crunching. Theoretical only gets so far, like the physicist that did some calculations regarding a particular NASCAR race. He figured that based on the curve etc of a particular track the max speed of the cars would be 165 mph. The actual speeds were 163-167 mph so he was pretty close. He also points out that the quickest 0-60 times for cars should be in the high 2 second mark, based on the assumption that it would be hard to get more than 1:1 coefficient of friction between tires and pavement. His assumptions fall short here and there and there's a lot of hoopla on how dumb he is but those making the calls aren't taking his assumptions into consideration (1:1 coefficient of friction, no aero factors involved; once you negate those assumptions then obviously his calculations go out the window, or you have to recalculate to get new values). Anyway theoretical is good but I want to see how weight affects acceleration at high wattages, where 50 or even 100w is not that significant in the scheme of things, meaning it'd be 5-10% of total, not 30% or something. At 1000-1200w 50w is close to the margin of error, i.e. statistically not significant. That's what I want to test.