Adapting XT calipers to 185mm rotors

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G'day

I have just purchased a lovely new Trek Fuel EX9. My problem is with disc brakes. The bike comes with Avid Juicy 7s on mounts to suit 185mm rotors. The fork is a new Fox RL32 with Manitou style post mounts and is fitted with an adapter.

I want to swap off the Avids for some 2008 XT calipers (which I got cheap) and have a problem with what rotor size and/or caliper mounting I need. I need some clarification.

Am I right in saying that if I use the avid mounts I will have to get 180mm rotors? My reasoning is that I guess I would have to use 160s if I mounted the XT straight onto the post mount.

Are there mountings which can adapt the XTs to 185mm?

Cheers

PS they are standard post mount style calipers

G'day

I have just purchased a lovely new Trek Fuel EX9. My problem is with disc brakes. The bike comes with Avid Juicy 7s on mounts to suit 185mm rotors. The fork is a new Fox RL32 with Manitou style post mounts and is fitted with an adapter.

I want to swap off the Avids for some 2008 XT calipers (which I got cheap) and have a problem with what rotor size and/or caliper mounting I need. I need some clarification.

Am I right in saying that if I use the avid mounts I will have to get 180mm rotors? My reasoning is that I guess I would have to use 160s if I mounted the XT straight onto the post mount.

Are there mountings which can adapt the XTs to 185mm?

Cheers

PS they are standard post mount style calipers

If you use the XT calipers straight onto the fork mount you will need a 160mm rotor.

If you want to sue your existing rotor you will need a 160mm-185mm mount which can be gotten fairly cheap. have a look at http://www.chainreactioncycles.com/Models.aspx?ModelID=13717 Be careful as avid use 185mm rotors whereas most others use 180.

Thanks
I know I would need 160s without adapters but what about with the avid adapters for 185mm?

I decided to go with 160mm with the XT calipers bolted straight onto the fork posts. 185 would be a bit of overkill anyway.