Flat Mount disc Adapter- Help!

Hey internet,

Sorry to sound like a complete idiot, but I’ve just bought a frame with what I think are IS mounts and have flat mount SRAM hydro Rival calipers- I was wondering if anyone can let me know exactly the adapter I need? I’ve attached a couple of photos of the frame I have and the adapter in the photo is what I think I’m after.

I’m currently running 160mm rotors front and back, but can change this if necessary.

Any help would be appreciated!

2 Attachments

Correct if wrong, but I have not seen any IS frame/fork to flat mount brake adapters, only post brake to flat frame/fork?

I think the same. You cant put flat mount calipers on a post mount frame.

As others have said, can't be done with stock parts. If you used huge 230mm discs it might be physically possible to make an adaptor to fit FM calipers but you'd have to have them custom made. Can you switch to post mount calipers instead? That would work.

Pricey...

https://www.assolutions.ca/shop/adapters/flat-mount-adapter-for-is-frame/ ![]

I'd say quite reasonable price actually for a problem solver like this ! Smart conception...

Interesting, I wasn't aware anyone had productionised an ISO>FM adaptor. Adjusting the position of the caliper laterally looks like it'd be a total PITA though with those adaptors.

Yep, way more faff than conventional adapters and won’t work with all IS mounts (hence the cut-out clearance template).

I’m guessing you’d position it with shims on the IS mounts (as per an old IS caliper)?

I’m guessing you’d position it with shims on the IS mounts (then shouting at it before throwing the IS shims in a fit of rage, finally storming out to the pub - as per an old IS caliper)?

I'm using this adapter from 10 months and it works perfectly. It comes with shims, even if I needed none of them on my bike.

I had some Hopes like that.

You’d take the wheel out, even just for a second, and need to reshim the caliper when you put it back in.