hankrivers

what are the benefits/drawbacks of different legnth cranks on your bike?
i think my stock cranks are 170mm, but the ones i want (shimano XT) come in 175 and 180mm legnths.
what diffrence would it make for me?
i am 6'1" tall and wiegh 215lbs. if it matters.

ljbike

There was another thread about this just a couple days ago. There was also a reference made to an article giving the answers to your questions. You might want to look it up.

Generally speaking a 175 crank would be about right for your height. It will give you a little more leverage than a 170.

(The reference is in the Road Cycling Forum: 172.5 vs 175 cranks)

adaze

personal preferance really, your only looking at 5mm, so its not going to change your life. shorter ones are slightly stronger, obviously, but if you get good quality ones like the xt, (i think they are made of duraluminium (sp?)) you wont have probs unless you suddenly take a liking to 10ft drops.

a2psyklnut

Shorter cranks are better where clearance through turns is an issue. Downhiller and duel slalom riders use 160 - 165 mm. A lot of North Shore Freeriders use them as well.

Longer cranks will give you more leverage and torque. Many single speed bikes have longer cranks to help during tough climbs. I've seen a guy using 185mm on his 1-speed.

If you've got a long inseam, they will also suit you better. If you're doing a lot of XC riding, you should go with either the 175 or the 180 mm.

For a mtn bike, most come standard with 175mm and so you'll find that size more readily available in shops and on-line.

L8R