valdlaw wrote:
Tom if you plan to use them for TT's and round rings for the road bike won't you constantly be working against the muscular adaptation developed on the Osymetric rings? It took me a couple of weeks to feel completely comfortable "adapted" to the Osymetric rings on my TT bike. Consequently I switched to Osymetric rings on the road bike as well to keep from "readapting" to round rings.
In a word...no. I actually found when riding the Osymetric big ring combined with a round small ring that it only took a minute or two of riding to "get used" to the different feel when going from one ring to the other...the funny thing being that it didn't matter if I was going round -> non-round, or non-round -> to round, after the transition my pedaling felt "jerky". That shows me that (at least for me) any "adaptation" occurs fairly quickly.
BTW, after talking a bit about this subject with a guy much smarter than me (Hi Jim!) there's something about that "adaptation" thing which would tend to imply that non-round rings won't really "work". Here's why: the use of non-round rings is built on the assumption that one can change the joint angle velocities (and thus muscle shortening speeds) in the upper portions of the leg (i.e. the hip and knee joints) as compared to when the legs are attached to a crank with round rings. The "problem" is though, that there are redundant degrees of freedom in the leg structure (i.e. the ankle joint..and even foot flexure) that may prevent this. Here's the kicker though...one can potentially vary those joint angle velocities around the pedal stroke by a much greater margin than any non-round ring could accomplish, just by changing ankle flexure.
The body is an amazing thing...and typically "left to it's own devices" will find the preferred joint angular velocities and muscle shortening speeds. So, what may actually be happening during those "adaptation" phases is your body re-learning how to pedal so that your preferred joint velocities are accomplished. Make sense? This is most likely the reason why, despite some analytical findings to the contrary, little to no power change between round and non-round rings is found through the vast majority of the scientific literature.
So...to get back to your question...I'm not that worried about having different rings on the road bike and TT bike, since my only reason for thinking they may "feel" better for me on the TT bike is probably more of a fit question, and something that I may be able to accomplish anyway with some shorter cranks I have coming my soon ;-)
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