I am trying to put some Shimano XT disc brakes on a 2001 Canondale hardtail frame. The adaptors on the brakes line up fine with the mounts on the frame but the calipers dont come away from the frame enough to reach the rotor.

I know some brakes use shims but these are out by about 10mm

Any ideas?

Mike

You’ll need an IS to post mount adaptor for whatever size rotor you’re using…i think

I know that some of the xt brakes need xt specific adapters, i had this problem but it sounds to me like you have the worng adapter entirely, are you using a rear adapter on the front maybe?

SCRUB ORIGINAL POSTING

Re-reading your post, are you saying that discs wont go through the slot in the calipers? i.e. they need to move 10mm left or right?
You may need to shim a few mm at the most, not 10mm though.

What fittings are the frame and forks?
Pics might help too?

pics?

Using a front adapter on the rear would put the caliper 10mm too close to the centre of the wheel (ie a 160 front adapter works with a 140 rear disc), so given lack of other information, that seems the most likely issue to me.

That’s how I initially read the post, but on re-reading it sounds like the calipers don’t reach the disc horizontally.
This couldn’t be anything to do with those CODA brakes that Cannondale used to make? i.e. not a std offset?

Yep – the bike did have coda brakes which i have removed and i am trying to fit 2010 xt brakes. Bigyinn is spot on – the caliper is out by about 8-10mm horizontaly!

The coda brakes are pants – the spacing on the hub also seems to be different when compaired to my xt wheel – on the coda hub the rotor is much closer to the end ofnthe axel then on the xt wheel!

Mike

So I assume that the caliper (when looked at from the rear of the bike) needs to move approx 10mm to the left (or nearer to the frame)?
So the frame is IS (of a fashion)?
What hub are you trying to use with the XTs? The coda one?
Might be worth binning the coda hub unless you have enough material on the frame to remove 10mm of mount? (I doubt it and wouldnt want to perform surgery on a frame) or get the hub machined down to remove 10mm of material to put the disc in the right place.

Are you putting the adaptor on the correct side of the IS mount (the mount on the frame)??

DrP

Just pack it out with m6 washers.

If i’ve understood the OP, packing is not the answer….

the calipers dont come away from the frame enough to reach the rotor. I know some brakes use shims but these are out by about 10mm

I read it as the disc mount on the hub is 10mm offset towards the hub centre, to a std modern hub. I’d pack the caliper out with washers so its aligned over the disc. 10mm is a lot though, given the shear force that a big disc could create.