[epicaz]

I'm in the of installing some XT's disc brake levers and calipers.
The fork is FOX F100, the rotor is a AVID 160mm.

I noticed the Avid caliper had 2 sets of spacers on the IS bolt for mounting. The Avid bolts are longer than the supplied XT's one.

Do I need the special shimano adpater or will the one that I was using for the Avids work?

The XT's won't mount up directly to the IS post, the caliper body hits the mount.

I can use a spacer with the Avid mount but how much caliper needs to grab the disc, the more spacers I use, I imagine the less disc I'm grabbing.

 

[Hardtails Are Better]

IS and post mount are different things. F100s have been both at different points. Which do you have?


Either way, you should be able to just bolt the Shimano caliper to whatever it was that you were using for the Avid, without any of the CPS washers, and the shorter bolts Shimano supplied.

 

[epicaz]

It's IS mount, it needs the adapter to work.
I'll try w/o the any of the spacers, but it seems the body hits the adapter. I'll take a pic.

 

[reptilezs]

use the macro feature on your camera and remove the washer that is in the way or use a smaller one

 

[epicaz]

use the macro feature on your camera and remove the washer that is in the way or use a smaller one

I'll try for better pix, but it's not hitting the washer in the fore ground. The XT caliper has curve in the body and that hits the IS adapter.

 

[bdundee]

I can't really tell by you pics, but you don't use the washer stack from the Avid brakes. Sometimes you run into clearance issues between the caliper and the IS adapter and all you need to do is file the adapter down for clearance. I'm running a avid 160mm IS adapter with Xt's and they work fine. Though mine had already been filed to be used with Hayes strokers so I can't tell ya if there where clearance issues to begin with.

 

[epicaz]

I can't really tell by you pics, but you don't use the washer stack from the Avid brakes. Sometimes you run into clearance issues between the caliper and the IS adapter and all you need to do is file the adapter down for clearance. I'm running a avid 160mm IS adapter with Xt's and they work fine. Though mine had already been filed to be used with Hayes strokers so I can't tell ya if there where clearance issues to begin with.

That makes sense. Sorry about the pics, I'll take my dremel to the adapter.

 

[hatake]

Invest $10 into something like this:
http://www.jensonusa.com/store/product/BR407Z47-Shimano+Fork+Disc+Brake+Adapters.aspx

Doubt if the adapter breaks, but you never know how the metal cracks and fatigues, together with extra spacers going in there would affect the overall integrity of the brake system. Better than a trip to emergency room.

 

[bdundee]

Invest $10 into something like this:
http://www.jensonusa.com/store/product/BR407Z47-Shimano+Fork+Disc+Brake+Adapters.aspx

Doubt if the adapter breaks, but you never know how the metal cracks and fatigues, together with extra spacers going in there would affect the overall integrity of the brake system. Better than a trip to emergency room.

No extra spacers needed and no the adapter won't break. Heck some people cut the center out of them to save weight. Sometimes you just need to use your imagination. Building your own bike sometimes involves a little imagination.