Shimano has today revealed a 105 groupset revamp, due to land on UK shores in June, as well as new road hydraulic discs that will be compatible with mechanical shifters and land in August.
Revamped and now 11-speed, the 14/15 105 group gains trickled down technology from Ultegra and Dura-Ace. Importantly, the new 105 will be compatible with the manufacturer's hydraulic road discs that are designed for mechanical shifting.
The chainsets inspiration is fairly obvious, with a four-arm Hollowtech 2 design, borrowed from the current Ultegra and Dura-Ace. What's more, the change signals greater stiffness and weight reduction, with bolstered areas around the chainring to further power transfer. Crank lengths will come in 165, 170, 172.5 and 175mm.
50-34t, 52-36t or 53-39t gearing options are to be available. The 11-speed cassette provides small gear steps that optimize rhythm and cadence control and is available in: 12-25, 11-28, 11-32. The chain is treated with Shimano’s SIL-TEC coating to run smoother and wear longer in all conditions.
The shift levers have a compact grip which provides more comfort and control during a ride. The lever can be customized for different hand sizes with a 10mm screw type reach adjust. The front derailleur has a longer link arm combined with a new spring mechanism. Also the rear derailleur has a new spring mechanism and cable pitch, which provides robust adjustability.
ST-RS685 Road Discs
For those wanting to embrace the road disc revolution, but without the electronic assistance of di2, Shimano has announced a version of its hydraulic road discs that will be compatible with mechanical shifters, such as those mentioned above.
Shimano’s engineers were able to include a mineral oil reservoir and brake system all in the compact and ergonomic mechanical lever. Hydraulic disc brakes maintain high consistent braking performance regardless the weather conditions through heat management and brake power that can be tuned to riding conditions, terrain, riders’ size and abilities.
The lever features a 10mm reach adjustment to customize the control for people with smaller or larger hands.
The brake caliper that Shimano introduced last year (BR-R785) has been updated and replaced by a new brake caliper (BR-RS785). This caliper has improved cable routing. Instead from the lever to the outside of the caliper, the cable runs now to the inside of the caliper (straight type).
Shimano equipped its hydraulic disc brakes with Ice technology - a rotor designed for better heat dissipation. The clad rotor blade, which has a three layer-sandwich structure of stainless steel and aluminum, provides a better radiation performance that reduces the temperature faster than has previosuly been possible. There are two FREEZA SM-RT99 rotor size options for customizable braking performance. 140mm as a standard and 160mm as an option for people who require more brake power.
If your customer is after the wheels to match, Shimano also reveals the tubeless WH-RX830. This 11-speed road wheel for hydraulic disc braking is carbon laminated and has a 17c wide rim. This improves stiffness, driving rigidity and matches the trend for wider road tires. Together with Shimano’s disc brake system the wheels provide a powerful combination of stopping power, control and comfort. The wheels have Cup & Cone bearings and a center lock rotor mount for 140mm and 160mm SM-RT99 rotors.