yonderboy

I'm looking for some new cranks to replace my FSA Gossamers that keep getting loose. The only question is my crank length.

I currently run 172.5s for extra cornering clearance. On sprints I feel like I could use the extra leverage from 175s, but most of the courses I ride are 90 to 180 degree flat corners. Pedaling through the corners is very important. On my track bike, I run 170s without issue, even on Alpenrose's 43° corners and flat crit courses.

A lot of ground can be made up in the corners, but I'm wondering if I'm shorting myself by not having the extra leverage longer cranks can afford me. I'm 6'3", so I could put that extra 2.5mm to good use.

merlinextraligh

175mm cranks and speedplay pedals.

assuming your legs and torso are relatively normally prooprtioned, most calcualtors would say at least 175. Then speedplays to get a very good lean angle.

dl613

+1-I'm 6'2" and use 175's with Shimano pedals and have enough ground clearance through fast corners so the Speedplays would be even better. Good luck.

nitropowered

175's

Dubbayoo

I would think at the end of a sprint you'd rather have the higher cadence than more leverage in a crit.

DrPete 

Just use the crank that fits and make sure you train in the corners with the same setup. Then you'll develop your timing as far as pedaling into/out of the turn.

fujiacerider

I run 180s without any problems. I don't think I can remember a single time my 180s held me back. If it's that much of an issue for you, try braking less. I highly doubt you're at the limit of your tires anyway. If you're worried you won't be able to start pedaling soon enough, think about what you're saying. So you're leaned in too steeply to pedal. Once you're straightening up, you'll lose probably less than a tenth of a second of pedaling before the guy with the 170s, and that's assuming you're both at the precise limit. Face it, neither one of you are.
Those split seconds add up in auto racing, but when you're in a pack of 30 other guys with varying levels of ability, it matters not at all. And if you're off the front in a break of three? 2.5mm will not be the reason you can't keep up. Do what's comfortable.
If you're that worried, get a Chris King rear hub while you're at it. The extra-quick engagment of the racheting mechanism will more than make up for that 2.5mm of crank length.

ed073

at 6 foot 3, I reckon you should be on 175s for all road events.

Even longer if you have a TT set up.

your comment about "pedalling through corners being very important" is a bit of a worry, though.

DrPete 

Well said. In lower-cat crits, just staying off the brakes in the corner will give you a much bigger advantage than that split-second from having shorter cranks.

yonderboy

I'm talking about producing more torque than RPMs, but I see what the general consensus is.
It sounds to me like I should just go for the longer crank and either hang off in the corners or coast. Really, I'm more worried about clipping a pedal through a long, flat corner than being able to hang onto the wheel in front of me.

YMCA

I have run every size from 170 through 180. I found no difference in ability or technique from using any particular size. I'm 74" and use 170's now, because I like to stay on top of the gear as often as possible, in order to respond in a snap to jumps, etc. It is more a mental thing for me to have the shorter cranks. They make me feel better about spinning up quickly and having a little extra room in the corners.

urbanknight

I think the OP wants to pedal COMPLETELY around the corners, as I used to do in many flat crits. In that case, clearance is needed because if you're not pedalling at all and the others are, you're losing ground. That being said, I still had no problems with my 175s and Look pedals. You have to learn to control how much you lean, then lean the body to gain the balance. Thinking geometrically, even 10mm is not that big of a difference.