It started out with Shimano engineers just trying to simplify & better integrate their fast-growing XT-level E-8000 STePS e-bike drive setup for mountain biking. While the bulk of the system is the bottom bracket mounted drive motor, a downtube mounted battery, and the electronics that run internally to a bar mounted display/controller, there still has to be the rear wheel speed sensor to keep everything in check at the 25km/hr pedal assist limit. Up to now that has left a speed sensor attached mid-way on the chainstay and a conventional wheel magnet attached to the spokes. Shimano techs realized that all these new e-bikes were getting disc brakes and with a little planning they could tuck a lower profile speed sensor into the dropout and put the magnet on the rotor for a much cleaner solution, better protected from trail hazards. We’ve got a look at Shimano’s simple prototype and now the finished production solution coming soon. Plus they’ve added even more integration opportunities with new light accessory connectivity, new remote switch & more…
The speed sensor integration was a really simple idea, and more than anything just required a new low-profile sensor design that could be mounted close to the dropout and get fully routed inside the frame. This prototype we previewed was literally just a powerful magnet glued onto a standard rotor, but Shimano has taken it a bit further for the production rotors.
Two eMTB specific rotors will be offered, the XT-level EM800 rotor with IceTech sandwiched alloy core construction, and a XTR-level EM900 rotor that adds on Freeza alloy cooling fins and a lighter spider as well. Both versions get a removable magnet that attaches to the backside of the aluminum centerlock carrier.
Both rotors will be available in both 160mm & 180mm diameters.
Then to actually track the rotation of the magnet-equipped rotor, a new low-profile sensor (SM-DUE11) will bolt onto the inside of the non-driveside chainstay and can be routed internally back to the drive motor & controller. The new speed sensor is compatible with both STePS MTB (E8000) and Shimano’s lighter-duty E6000 e-bike systems.
In other e-bike integration, Shimano has a new E6002 drive unit for more urban bike applications that lets you plug compatible front & rear lights directly into the motor’s 2A accessory ports for a simpler installation and be powered by the single battery setup.
The new motor also gets an updated Walk Assist mode that allows rides to push and hold any of the controllers buttons for 3 seconds to help push the bike up steep ramps at a walking pace. Plus E6000 gets lower profile cranks for more shoe clearance and a new more ergonomic switch setup.
All of the new e-bike tech from rotors & sensors to the new E6000 kit will be available in August 2017.