crank length???

fattyatkinson

the variation in crank length is only 5mm. what difference does it make and will i notice such a small difference in size? what is standard??? thanks

redddraggon

The variation between what cranks?

You can get a way larger difference than 5mm.

I'd say the variation from 170mm to 175mm might be slightly too much. I've got 170 and 172.5 on my bikes and can't really tell a difference between them.

Cajun

http://www.cptips.com/crnklth.htm
http://www.cptips.com/knee.htm

maddog 2

simplistically....

bigger cranks mean more leverage, but a bigger circles for your knees and hips to move in, and thus a slower cadence.

smaller cranks don't produce as much power, but are arguably easier on your knees and enable you to spin faster (which is generally viewed as a good thing). They also give you more ground clearance.

as for whether you can tell....... depends on how sensitive you are. Some can some can't.

The practical differences aren't great - you won't go from a donkey to a stallion - but over time, you should find one you prefer. I run 172.5 on my roadie and 175s on the mtb (although I may change this next time round)

Hudster

What you're used to also makes a big difference. Mountain bikes generally come with 175mm cranks as standard and road bikes 170mm. I've ridden mountain bikes most of the time and therefore always found 170mm cranks to feel wrong when I tried them out. I ended up spec'ing 172.5mm on my first road bike.

However, I have since been using a pair of 170mm cranks and have done a lot of riding with them and I now have to say I prefer these. So I think training has a lot to do with which works for you.

Can certainly tell the difference between them all anyway.

cougie

I cant tell the difference. Wouldnt different pedal/shoe combinations also be a factor too ?

suze

I ride cramks between 165 track bike, 172.5 on my road bike and my mountain bike has 175.

And I have a different pair of shoes for each. This is because I can't standardise my pedals as yet. Though I generally ride Keo's on the track and will be putting these on my road bike as well. As for can I tell the difference, Well sometimes for about 5 min on my mountain bike. Then I forget about it and just enjoy riding a different bike in a different style.