thehammerdog

Question for you. I have two road bikes my new fancy carbon 10 speed with 175's and an old school 5 speed 1980'2 steel with 165's......road both this weekend and was wondering is there any injury issues with going from one to the other. I ride them both hard and was simply curious if a change that large could be a problem. No issues yet.

thanks

bitingduck

Probably not. I've always ridden 165s on the track, 170-172.5 on the road, and 175 mtb. I've had long periods where I was probably spending half my time on the track and the other half road, with occasional mtb. There have even been days when I've ridden all three. It's pretty transparent, though the first few minutes trying to spin fast with long cranks can feel odd.

iab

Doc, it hurts when I do this.

Stop doing that.

Why worry about something that hasn't happened? But seriously, 165s on a road bike? 165 road cranks were generally special request back in the day. Those have to be somewhat rare.

rishardh

Make sure your saddle height is set according to the crank arm length. ie A bit higher on the bike with the shorter cranks so your legs will be extended the same amount. 10mm is a big gap if you are pushing hard and putting up a lot of miles. An ounce of prevention is better than a pound of cure.

Closed Office

I have bikes with different lengths and don't even notice the difference when pedaling. I do when I have to replace one and have to match the size to the other side. I can't remember what the lengths are, and if they are as different as yours.

hybridbkrdr

I think it may depend if you have chondromalacia in your knees or not. I read one message saying that longer crank lengths could cause knee pain. I don't know why I was "ignorant" enough to buy some 175mm cranks myself with chondromalacia in my knees. I ended up deciding I'll use them anyway to complete a touring build because I bought a whole bunch of bike parts more than once when I kept changing my ideas about what I wanted. So maybe I'll find out later if it was a mistake or not. I mean I intend to put all the "unwanted" bike parts on a "Frankenstein build", sell it once I've tried it for several months to make sure what I want with the next project then use the money to complete the other project.