Shimano unveils hydraulic disc brake system for road bikes

Launched to coincide with the release of Shimano’s electronic 11-speed update to Ultegra is the Japanese company’s first foray into disc brakes for road bikes.

In contrast to previous road race innovations from the company, Shimano has chosen to launch it as an Ultegra option rather than Dura-Ace as it’s not yet ratified for use in road racing. This means that for the time being at least it’ll be constrained to training, commuting and sportive events.

Running the Shimano internal code number of R785 the name belies the interest and potential significance of the new components, if some industry people are to be believed every new bike will be running disc brakes in a few years time – we’re a little more sceptical, all the same, it’s a very interesting development.

Looking a lot like a slimmed-down MTB disc brake, the ST-R785 caliper uses a post mount for attachment and obviously requires specific mounts on the fork and rear of your frame – so you’ll need a dedicated frame to benefit from the disc brake revolution.

The reason Shimano launched the brakes at the same time as the 11spd Ui2 news is that you’ll need to run electronic shifting with Shimano’s hydraulic system.

Whereas on SRAM’s hydro disc brakes, HRD, it’s a mechanical shift system, Shimano has preferred to offer it only with electronic. Presumably this is because the master cylinder is built into the body of the hood just where the mechanical shift mechanism would normally sit.

As standard, Shimano suggest you’ll need a 140mm disc rotor, they will also offer a 160mm version and 180mm should you require the extra stopping power or more correctly heat dissipation of a bigger disc. Also lifted from the MTB side is the Centre Lock mounting system for fixing the disc to the hub. Dubbed ICE technology the Shimano disc includes additional fins to help cool the brake.

Whilst we’re yet to be convinced of need for disc brakes on road bike the undisputed benefit of better braking regardless of weather conditions sounds like a great idea to us.

Shimano Ultegra Di2 11-speed launched >>



STI gear shifters ST-R785 Di2 inc caliper £599.99
Disc brake rotor – single £54.99

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