Hey all, I'm looking at replacing my old Juicy 5's with some slightly used Elixir CR's, but the Elixirs came off a bike with post mounts. My fork has IS mounts, so the seller's adapter's won't work. I was hoping to just re-use my adapters, but does anyone know if Juicy's and Elixirs have the same hole spacing?

But then the next issue - the new front rotor is 203mm but mine is 185mm. If I want to use the new rotors then I guess I need to get new adapters regardless. I assume they're fairly cheap and standardized? What's a good source? Would most LBS's stock them?

I'm not entirely sure, but probably, and I don't think this should be much of a problem. With a ruler and a cellphone picture, plus a little googlin', you should have the answer in short order.

Does this look like what you need? I think it might be it.

http://www.bikebling.com/Avid-CPS-Front-Mounting-Bracket-203mm-Rotor-p/avid-00.5315.012.040.htm

If not, there should be one to fit your needs:
http://www.sram.com/avid/products/cps-mounting-brackets

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You can try to use the old adapters, and if they don't fit, then you will have to buy new ones.
Going from 185mm to 203mm rotors, you will have to get new adapters. Bike bling has them for about $12. If you go to other shops, they may have them over $20, just have them price match Bike bling.

The Elixir brakes have two sets of washers below and above the calipers.

Yes you can reuse adapters. Elixirs and Juicys are the same.

New X0 trails no longer use the CPS bolts but you can reuse the adapter.