Dura-Ace 9170 lever/caliper compatibility

[RobJ]

I can't seem to locate the info on the Shimano site or elsewhere. Does anyone know if any of the post mount calipers (like 785) play nicely with the new 9170 Di2 hydro levers?

[John H.]

If you have all the correct parts for the hoses, they should work fine. A buddy runs 9170 with XTR 9000 race post mount.

[thermalattorney]

Yup! I run my 8070 levers with an R785 post mount rear brake. Make sure to buy the road brake hose kit that includes the lever nut. The model is BH90-JK-SSR.

Shimano switched from the BH59 hose in the first-gen (R785) stuff to the BH90 hose for the second-gen (R9170/8050) models. The only difference is the internal diameter, which does change the feel slightly. Not better or worse, just different. Since the OD hasn't changed you can use either hose, *but* the nut you need to attach to the lever only comes in the kit mentioned above.

Good luck, it's a great lever & brake combo!