Originally Posted by
gregf83
+1. I climb a 3 min hill on the way to work at anywhere from 55 to 100RPM. If I'm transitioning from the flats to a hill I'll often start in the big ring and just wait until my cadence drops to about 70 and then switch from the 50 to the 34 up front. No need for complicated shift patterns just a little variation in cadence. Studies have shown there isn't much change in efficiency over a broad range of cadence.
That's got to be true... which is why the 175mm crank arm paradigm really is nothing more than a rule that has been accepted based only on unquestioning adhereance to prior practices. The conventional thinking that has grown up around what, as it turns out, is just an arbitrary length is that going to a shorter crank reduces leverage and consequently would have a negative impact on performance. However, when tested objectively, actual experiences even for longer legged riders has shown that crank lengths even less than 165 (which is about as low as is readily obtainable in the mass market) may actually help riders produce more power on the road, allowing riders to increase gear inches with no greater increase in perceived effort.