BikingBrian said:Well, my French is a little rusty, but I gathered that basically it's a system to get through the dead spots faster/with less effort....so the same concept as ovalized chainrings, etc. This "dead spot" thing is beating a dead horse - it's been shown that pro cyclists produce power only in the phase where you are pushing, ie forward, and more importantly, DOWN. The study I read about found no sizable power application in the "pulling" phase, iow they use their quads almost exclusively, as very little power is produced by the hamstrings. SO....getting through the "dead spot" faster, or trying to produce more power in that phase of the pedal stroke appears to be meaningless. This product does nothing new, it just reinforces old myths.
I think you are mistaken here, as the path of the pedals is circular and of standard radius (175mm, ill have to check), I believe as the crank arms get longer their centre of axis moves away from the bb such that the pedal path is circular and app 175mm diamater.ScienceIsCool said:I forgot something. You also need to compare the results against normal cranks of different crank lengths. The max extension on these is something like 187 mm. How do the results compare to fixed length cranks of 180, 185, and 190 mm? It could be that the test subject(s) were fitted on the bike such that their optimal biomechanical efficiency is at ~185 mm.
Bigbananabike said:Ok, but Rotocranks(I think that's what they're called) that are independent of each other help to produce more power in the hamstrings which(reading riders write up) seems to help riders go faster.
Actually rotorcranks let your quads directly help your hamsrings, which are not in an optimal position biomechanically to produce much force. Recruitment of the hamstrings and the demands on them are lessened by Rotor cranks and Q rings.