Using a MTB Cassette on a Road Bike

[DocZan89]

Was considering putting a MTB cassette on my Road Bike to help me with hills. Has anyone done this? Would really appreciate opinions and advice.

Thanks,

Rosanna

[OakLeaf]

Make sure your rear derailleur will handle the big cog, and the range. Depending on what you're putting on and what you're replacing, you may be able to use your stock RD, but most likely you'll need a mountain RD.

[Crankin]

I have one on my custom Guru. Just make sure you do all the things Oak says.
I've never had an issue. My DH did, and I believe it was the chain not being perfect for the cassette. Actually, he switched his higher level cassette to the one I have and now it's perfect, too.

[eofelis]

Are you using SRAM or Shimano?

Both of my road bikes have mtb cassettes and rear der on them.

My steel Gunnar Sport has 9 sp Ultegra triple with an XT 12-34 and XT RD. I've been riding this set up for about 10 years now. I've done some big Colorado passes with it, 10ft+.

My carbon fiber Spec Ruby has 10 sp Ultegra triple with SRAM 12-36 and XT Shadow RD. Works great!

My bf has set up several bikes for friends like this.

NOTE: to do this with a 10 sp set up and 11-36 you need to use a 9 sp Shadow RD. To use an 11-34 you should be able to use a 9 sp non-Shadow RD. The big thing here is that you have to use the 9 sp RD as the 10 sp RD will not work with the 10 sp shifters, I know that sounds strange, but it's true. I recommend a K-Edge chain watcher as the chains like to jump when you have the huge cassette on there. You'll need a new chain too as you'll need a longer chain than you probably have for all this.