As my kids grow, I'm needing progressively longer cranks, but unfortunately, my tallest kid is still too short for commonly available 170mm cranks. At the moment, a set of 160mm cranks would be perfect. For shorter cranks, I have simply taken 175mm cranks and shortened them. However, for crank shortening, the process takes at least 20mm off the length of the original crank arm, so 175mm cranks end up at 155mm or less. This means, using readily available (and cheap) 175mm cranks I can't make a set of 160mm cranks.
As a result, I've been looking for 165mm cranks off-the-shelf, but have ran into a few issues:
- 165mm cranks exist, but most are 110BCD which limits the single ring size to 34t;
- some DH and AM cranks come in 165mm but they are way too heavy, expensive and generally unsuitable (eg 83mm BB width etc.)
So far, these are the options I've been able to come up with:
Of course, if money is no object:
- Shimano FC-M980 XTR Trail Crankset
- Shimano FC-M785 XT Crankset
- Canfield Bros AM cranks - these are available in 155, 160 and 165mm (and longer), they are fairly lightweight and come in a 68/73mm BB version. If you're after a 160mm 4-bolt crank then these are one of the few options available.