I found the following topic on FGF - http://www.fixedgearfever.com/modules.p ... sc&start=0
Gentlemen....just to add to the myth, if you can cast your minds back to the 2000 Sydney Olympic Games, and remember that the German Teams Pursuit were the first team to ever break 4 minutes. Then it was told that they all used 180mm cranks, and so we all tried to change. Subsequent revelations will suggest that it was something other than long cranks that won them the gold and set that time.
To add to this comical scenario, in the early 2000s NZ employed one of the most succesful endurance track coaches the world had seen, a man who took Australia to many many world and Olympic titles through the early 90s. When he came to NZ he would make the riders all train on the track with a certain length crank, and then on race day increase the crank length. This without any changes to position... well hello..if you have set the rider up in their optimal position...and then change something...its not optimal anymore!!!!!!!!!! Unfortunately when I inherited the NZ Team, there were still a couple of guys that would still do this...and they still do. When I asked why this was done to the respective coach...he couldnt give me a categoric answer.
With our Pursuiters, we have some big guys...and we tried all sorts of crank lengths from 170-180mm, and I have to tell you that most went better on 172.5mm.
But to add a little fuel to this firey debate... consider this..if your car gets a flat and you have to change the wheel..you get the jack out to lift the car...if you hold the handle close to the jack..its difficult to lift and push...but if you hold the handle right at the end where you have more leverage...it is far easier to use.
That is where the theory of a longer lever is easier.
So...this is my opinion for what it is worth...power is measured through the bottom bracket, or rear wheel and as such it doesnt measure the actual force on the pedals. It measures power output, but not specific power through the pedal. Even though the crank is longer and at the pedal is easier to turn at slow rates, the cadence doesnt alter irrespective of what crank length you use...but....your pedal speed does increase as the crank is lengthened... because it has further to travel through 1 rpm.
Therefore a longer crank should assist with acceleration to a given cadence, but then the reverse occurs..the faster the cadence the less efficient your pedalling becomes because of biomechanics, and of course he fact that with the longer crank the pedal speed is increased.
Maybe Im right..maybe Im wrong...
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