Morning stw

Can anyone show me a link (preferably crc) to the adaptor I need to allow me to tun a 180mm rear disc. Frames an sb6c if that makes any difference? Currently running 160 and want to try an alp proof the bike.

Cheers

Is the sb6c a post mount frame? Caliper straight onto the post mounts?

I’ve just done this myself and took the mount from the fork.

Yes it’s post mount. Non of the adaptors say “rear” hence my confusion. Want one that comes with longer bolts if possible

Front or rear doesn’t matter, just the numbers of that it is, and what it goes to.

My frame takes a 160mm rotor with no adaptor so I fitted a 160 to 180 post mount to post mount.

Two bolts fix the adaptor to the frame, two more fix the caliper to the mount.

Do some of them just have holes through and longer bolts? In my head this is a better solution.

I’m not sure they could without the use of cup and cone washers. Brake mount standards aren’t radial so it’s not just a case of raising th caliper up, there needs to be rotation to realign it.

I use Hope stuff, I can confirm theirs works and that it needs 4 bolts.

From the Hope stuff, it’s the relatively new “L” mount that you need.

Onzadog, what you say makes complete sense, shimano/bike manufacturer however no, supply the other type (2 bolt) on most of the bikes I see, so are they wrong? I will be checking pad/rotor alignment later this morning on my son’s bikes.

Seems the 4 bolt offset ones are only needed for 200mm+ rotors?

Pictures

Shimano 180 post mounts use longer bolts and a pair of cup and cone washers above the caliper. Sounds like they would be perfect for what you’re after.

Which brakes? And do you have an adaptor on there now?

Shimano, you need one of these in 180 flavour assuming your rear end is 160 post mount: http://www.chainreactioncycles.com/shimano-mount-adaptor-front-post-to-post/rp-prod13747

Guides or avids are a bit trickier – SRAM seem to assume we’re all on 140mm rear discs now so if your rear end is 160 without an adapter you need the bolt kit for a 160mm rear disc. Confusing – but you just need to remember your going up 20mm. http://www.chainreactioncycles.com/avid-disc-brake-spacer-set-hardware/rp-prod108156

I don’t personally like the longer bolts and big spacers but the sram 20mm adapter is oem only, you can’t buy them off the shelf.

Edit: Planet X have the sram/avid ones you need http://www.planetx.co.uk/i/q/BSAVPPBM/avid-post-to-post-brake-adaptor