Rear calliper spacer/alignment

alexm77

Happy Christmas everyone! After a bit of reassurance please. Bought myself a present of a first gen Cotic Soul frame, and switching bits over from my old inbred. Found a bit of an issue with the alignment of the rear calliper (SLX M666, 160mm rotor). If you see the below pic, I've needed to add about 2mm of spacers/washers to the IS adapter to get the callipers aligned horizontally over the disc.



None of my previous bikes have ever needed this, so hope I don't have a bent frame - all looks fine afaict. Wanting to check if what I've done is safe and the correct solution? It does mean the bolts are 2mm short of going all the way into the IS adapter. I have 20mm bolts. The only longer ones I can find need to be ordered from china and are 30mm, so would need cutting down, which could be a tricky job if they're some kind of hardened steel.

Thanks.

cobba

Did you loosen the bolts attaching the caliper to the adapter when you moved the brake to the new frame?

What you've done with washers is fine.

You could also pack a rotor out with shims.
https://www.syntace.com/en_GB/products/wheels/accessories-spare-parts/1154/disc-shim
https://novemberbicycles.com/products/centerlock-hub-rotor-shim-pack-of-4

alexm77

Yep, completely detached the adapter from calliper to clean. Glad it's ok then, but think I will try to source some longer bolts. Just a bit surprised a frame can have such high tolerances. Would assume they'd build it a mm or two over, then face it to get it bang on - was quite a posh frame in its day.

david7m

You can get 5mm increment cap head bolts on the bay. I'd also source smaller diameter washers, thicker so you only need one, in black