Shimano is rolling out a new disc brake standard specifically tailored to disc-equipped road bikes.
The new standard, known as Flat Mount, was developed in conjunction with leading road bike brands as a dedicated road-specific disc brake mounting system.
Claimed benefits of Flat Mount over the current 74mm post/direct mount and 51mm ISO mounting standards include a cleaner, integrated design, with no visible mounting bolts; a direct interface with the frame and fork for better alignment; and improved tool access to the rear brake caliper for brakes tucked between the seat- and chainstays.
Shimano states that the system is backwards compatible with post-mount brake calipers with an adapter.
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Details on the new standard are limited to two grainy CAD images
No word on which companies will be adopting this new brake mount. Stay tuned for more information.