With all the crank length discussions revived again recently, I decided to try some shorter ones for myself and see how I get on. I’ve had my Nimbus 2 26x3 for about a year now, and have always used the 165mm cranks that came with it. I think they suit me quite well, but now I’ve put some 152s on it to see for myself what all the hype is about
I put the new cranks on yesterday (and raised the saddle a bit) and went out for a test ride on some easy forest tracks to see how they feel. I have just done a few more miles of riding today, so in total I’ve probably done about 30 miles on them, not enough to prove anything but enough to get a first impression.
So, what I think so far:
General feel, mounting etc - exactly the same as the 165s. I honestly can’t feel any difference in mounting or “smoothness”.
Top speed - I tried a couple of sprints today on a smooth track and couldn’t go as fast as I could with the 165s (about 2mph slower). Probably not a fair test until I’ve had a bit more time to get used to the new cranks, but the wheel seems to wobble a lot more than it used to at high speed… the new cranks have a bit more Q than the old ones, so perhaps that is a factor.
Foot position - As I said, a bit more Q, so no problems with heel strikes, especially when feet get bounced about on bumpy descents. I like that, but is the extra Q affecting the high-speed stability?
Lack of torque - This is far more noticeable than I expected with such a small change in crank length. It seems more tiring to ride on rough surfaces or up hills, with far more chance of stalling unless speed is kept up.
Ground clearance - A useful extra half inch leeway in single-track and swerving round rocky bits.
Overall, it feels similar to forcing myself to ride a bike in a higher gear than normal - good for developing muscle strength but not very efficient.
Don’t get the wrong idea - I’m not giving up yet! It’s just that the negative aspects of the shorter cranks (mainly the surprising drop in torque) seem much more noticable than the positive ones (no heel strikes with my big boots, less likely to smack a pedal on a rock, oh and they look nice!) at this early stage. I’ll see how it goes after a few more weeks - will I be a convert or will I go back to the 165s?