What Crank Arm Length Do You Use

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Hello,

I have been out of riding for the last 4 + years. I burn't my self out training and doing the California Triple Crown in 2000. Now it is time to get back in shape. I still have my old faithful Klein Pulse converted into a single speed and am using 180mm crank arms with a 34-16 gearing. I ride in a hilly area and this setup worked great for me 4 years ago. Now I just purchased a Specialized Langster singlespeed with 170 cranks and I wondered what crank arm length would work best in the hills? By the way, I will turn 48 next week and I wonder about my knees. The stock 48-16 gearing has been changed to a 48-18 but more torque/leverage would be welcome. Would going to a 172.5 or 175mm crank help my needs?

Thanks,
Mike

I'd say go to 175 for hills. I don't know how tall you are, but the longer the better. I ride a Mercks EX pro single speed and am considering going to 180 mm to east the pain of hills. I also have it at 39-16 which I am changing to 39-18 first. Just the ratio change will save me alot of knee and back pain. Then we'' see if I need to expend the cash for the crank arms.

Hello,

I have been out of riding for the last 4 + years. I burn't my self out training and doing the California Triple Crown in 2000. Now it is time to get back in shape. I still have my old faithful Klein Pulse converted into a single speed and am using 180mm crank arms with a 34-16 gearing. I ride in a hilly area and this setup worked great for me 4 years ago. Now I just purchased a Specialized Langster singlespeed with 170 cranks and I wondered what crank arm length would work best in the hills? By the way, I will turn 48 next week and I wonder about my knees. The stock 48-16 gearing has been changed to a 48-18 but more torque/leverage would be welcome. Would going to a 172.5 or 175mm crank help my needs?

Thanks,
Mike

I have a langster too and change gears often, not the cranks as of yet. I have found that a 42x16 seems to be a good gear where you are spinning nicely and doing a decent clip. I'd play with the gears a little more before getting cranks. I am getting a 17 for the fixed side and think 42x17 will be a lot of fun. Good luck.

I ride a fixed-wheel on the road with 165 cranks. It feels like riding a bloody circus bike and is hard going on the hills, but I love it. With my bottom bracket height, I could probably go to 175's quite happily, but I don't want to spend any money on it (and there isn't a lot to select from when it comes to track bike parts here in Malaysian Borneo).

I wonder about my knees.
Obviously, this doesn't apply to everyone:
The smaller circles you cover with the shorter cranks are better for your knees, given any gear. Remember that 180mm cranks put your knees 20 mm further up than 170mm*, which combined with the faster angular velocity puts a lot of bad news in a little package.



*yes, my maths are just fine here.