Mountain Biking - Road crank on MTB

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August Spies
07-08-04, 08:13 AM
I've got a Specialized Hardrock...nothing fancy but does the job damn fine for someone who isn't a regular mountain rider, it's a few years old but still in great condition except for the drive train. Problem is that the crank is way too ****ing small for my uses. Since I use it for the road fairly often, I've been thinking about putting a triple road crank on, which ought to pump up the speed a little. The question is, how much would I have to replace to do it? I'm fully willing to get new shifters (the old Aceras are getting sticky), but are there any in particular I should get? Would a road shifter or a MTB shifter be better for the steep change? I've got no trouble spinning a 52 tooth, especially with SPDs (which currently skip the chain like a mother).

Any advice?

Dannihilator
07-08-04, 08:44 AM
Don't do it. Just get a mtb crankset in which the crank arms are longer and just get a new set of Aceras or go up to LX. Road shifters do not work on mtb's. And the chain skipping is a sign that the chain and cogset and chainrings are worn out. Have you changed them since 2000?
roadfix
07-08-04, 12:35 PM
You may encounter chainstay/crank clearance problems by installing road cranks on a Mtb frame. It'll be a lot more practical to simply replace with a larger mtb chainring.

a2psyklnut
07-08-04, 02:11 PM
This can become a somewhat troublesome modification.

First, going from a 44 tooth outer ring to a 52 (and consequently the other two) may have clearence issues with the drive side chain stay. To overcome this you could possibly go to a wider bottom bracket. This might however really mess up your chain-line. Also, chances are that you'll have to also use a road front derailleur.

Not saying it can't be done, it just may get more and more complicated as one fix may lead to two more issues.

You could always just replace your cassette from a mtn cassette (prob a 12-32) to a road cassette to an 11-28. this won't have too dramatic affect on your top speed, but will keep you on your "high side" of gearing.

Doing this and maybe switching to a 46 big ring may provide you with enough gear to keep you happy without going crazy swapping parts.

L8R