XC 29er cranks length??

I recently got the KH 29er for riding crosscountry. the cranks on it have 2 different pedal positions 165mmm and 137mm. which length do you pefer for XC/mountain riding? the long or short?

Depends on the terrain, of course. The point of having multi-hole cranks is to be able to easily change length, so be sure to bring a wrench!

I currently ride 140mm cranks on my 29er so close to your 137mm hole. I find these great a great length for me, but the terrain around here is quite flat.

This has been discussed a little bit before, have a little search about.

I don’t know why anyone would want cranks that long. The standard cranks with that unicycle are 125/150mm drilled, 125 for fast XC or road riding or 150 for big offroad hills. If you change crank lengths you will probably need to change seat height as well- and unfortunately the KH 29" has a super-short seat tube with the end blocked, so you have very little tolerance for error when cutting your seatpost, and no room for shorter riders. I don’t know why they don’t use even a standard length seat tube- maybe they are targetting the Ken Looi’s of the world with shorter than standard legs. This old thread might be of interest to you if you want to hear opinions about 29er crank lengths, although it seems to predate the double drilled cranks, and some people may have evolved their opinions since then.

I leave mine at 125 for mostly flat trail riding, and 150 when it’s more rolling or technical. But I do carry a pedal wrench so I can swap if needed. Just carry a wrench, and try the different lengths as you ride. There’s not a right or wrong, just what you like and feel successful riding!