29er cranks

What’s the best length cranks for road riding (not to many hills) on a Nimbus 29 with big road tyre?

If you’re reasonably good at riding start with 125s, and maybe move shorter if it’s ok for the hills and you hae a suitable level of control.

125 is a nice hybrid length, but shorter is better for longer distances.

I’ve got a 29 qu-ax cross 100% standard, and the crank length i’ve got on it is PERFECT for me at least. it’s a 140 mm

I’ve recently changed from 152mm to 140mm cranks. I like to ride off-road really but have ended up doing more road riding recently. Am tempted to go down to 125’s again but changing cranks on a square taper hub and keeping them on tight has been fairly troublesome in the past.

It takes a bit of getting used to, but try some 100mm cranks. That’s what I use although on the flat I would try some 65mm or 89mm cranks. It’s hard to get those in ISIS at the moment, but I understand that Quax are bringing out some 89’s.

The 29’er with 100mm cranks is very smooth and not too bad for climbing either (because it’s so light compared to a Coker). I average about 22-23km/hr, which is only slightly slower than my Coker average speed. Max cruising speed for a couple of km’s was about 28km/hr, according to Nathan Hoover’s GPS. I did most of Uninam on a 29’er with 100mm cranks (www.uninam.net). It’s my main touring unicycle now, because it’s so much easier to transport compared to a Coker.

How to install cranks

Spray a little wd40 on the crank and hub, then wipe it off , so the parts are real clean. Put on a little grease on the parts interface. Then beat the crank on tight with a few whacks with a soft hammer. Or a steel hammer but use some wood to protect the crank.

This will distort the parts into closer conformity, while at the same time getting the crank on much tighter then you can with the bolt.

This is standard practice when installing tapered fly wheels on motorcycles and other devices. Otherwise, a tiny bur can hold the parts apart slightly.

For 29 cranks, I am using 150 now, but 125 or smaller I will try soon. I would say start with 150 for muni or 125 for the street. Ya gotta love how cheap the cranks are though.

Thanks for the replies I am using 125mm for couple of weeks and then going to try 100mm for more speed.:slight_smile:

I have a 28" rather than a 29", but there is only minimal difference in wheel size. I ride with 114mm at the moment, but only because that is the shortest size available in the cranks I like. I used to ride 110s. 125s are a bit on the long side unless you’re doing hills or very rough ground.

Funny thing is, on bigger wheels, you can often get away with shorter cranks. There is no obvious logic to this, but it seems to work for me.

This is my most disappointing post from you ever :frowning:

I saw the subject line, and I there was a Mikefule reply. So, I eagerly clicked it, expecting all the science and maths behind the various relationship between crank length and wheel size. But no. It’s a ‘this works for me’ answer. Anyone on here could say that, but I was depending on you for a more definitive and reasoned reply.

/tongue in cheek

FWIW 114s worked well for me commuting on my 29er


29er cranks

I have now tried 100s they were that short i had trouble free mounting. Now fitted 114s they seem smoother and a little faster than the 125s.