Looking at braking options for a custom build and am drawn to the simplicity and neatness of using the flat mount standard.

There aren’t a huge number of mountain bikes that I’ve seen using flat mounts but I guess it doesn’t mean it’s not possible.

Probably looking at either 160/160 or 180/160 with the mounts for these spacings being integral to the frame rather than reliant on adapters.

Thoughts. A step too far?

I think Cannondale use flat mount, Peter Verdone makes mounts too.

Flat Mount MTB

Disc brake mounting systems

Are you talking about a custom frame? I’m sure it can be done.

Why not? Think about future proofing tho.

You can get a post-flat adapter which looks pretty neat if you ever wanted a suspension fork anyway.

Might be worth asking Hope if they would do you a custom brakeset? Otherwise IIRC Sram use the same size pistons in their MTB and road levers but you’d either need to find them as spare parts or buy a whole set and cannibalize them.

While not always true the flat mount calipers are v small and often have smaller pad contact patch that off road calipers. This means faster wear and less friction area. I have also had and heard of many seal and piston issues on flat mount shimano road calipers.

Certainly have to watch the wear on my durace and grx calipers quite closely compared to the XT (admittedly 4 pistons so not fair comparison)

Having experience of both i wouldnt choose the flat mount standard for off roading

Might be worth asking Hope if they would do you a custom brakeset?

Or Hope RX4 calipers with Shimano mtb levers? They’re 4 pot, too.