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crank arm length(4 posts)

crank arm lengthnat_ct1
Sep 22, 2002 7:22 AM
im moving to a pretty flat location in the states. if i had to pick a style of rider i would say im a sprinter. currently my crank arms are 170. i am also a pretty heavy guy at 200lbs... would i benfit more from a 172.5 and mash the gears out rather than spinning? i am already running 39/54 chain-ring and am getting ready to put 11/23 casset on my wheels.
What is peoples preoccupation with crank length?PODIUMBOUNDdotCA
Sep 22, 2002 9:31 AM
No offence to you but everyone thinks 2.5 mm will make a huge difference but the thing is at best the difference will be hardly noticeable if at all... if it was a cm then ya maybe but still why??? Unless the person is racing and need that extra edge its not worth the extra money to buy a new set of cranks. Even then unless the person is pro/a high level racer/or sponsored its not worth it to fool around with.

On the track this is a widely debated topic but the thing is people accidentally do PB's on the cranks in "theory" they should not be able to on. And even then its a tenth of a second over a 10 second event so about 1%. If you end up buying a new set of cranks and fluke out by being right is that 1% worth it?

Also as for mashing as opposed to spinning if your on flat ground you don't need the minimal ammount more leverage if you classify yourself as a sprinter. You should be strong enough just to spin the 170.

Cheers,
Nick
PodiumBound.ca
Right on, brother! (nm)Kerry
Sep 22, 2002 5:08 PM
You'll hardly tell the difference, unless it hurts you.Humma Hah
Sep 22, 2002 5:17 PM
I grew up with 170's. I have a set of 175's that nearly crippled me on one gnarly century. I've ridden with 160's and love 'em.

My advice: don't increase crank length expecting any kind of advantage. You won't find it. Decreasing crank length might help ever so slightly for a good spinner, or will improve ground clearance if that's a problem for your riding style (MTB in the rocks, for example).

My own observation is that transitioning to longer cranks produces more knee bending, and all that squishing about of body tissue actually robs more energy. Any slight gearing change will be less than one gear on the rear corncob. Use what you're used to.