Motorcycle trials are the ultimate test of pure skill and fine control, and riders generally hop on rocks, power up near vertical hills or roll over narrow logs on lightweight two-stroke bikes, but powerful electric drivetrains are making a quiet bid for recognition.
Yamaha has now followed the launch of the TY-E electric trials bike in 2018 with a second generation prototype, which the company says has been designed to offer riders more fun than they can have on the two-stroke machines typically seen – and heard – in trials events, by tapping into appealing characteristics of electric drivetrains like powerful torque and fast acceleration.
The TY-E 2.0 is built around a new monocoque frame design with a X-shaped rib that makes use of composite laminates to keep things light and rigid, with the bike tipping the scales at somewhere slightly north of 70 kg (~154 lb).
Engineers have revised the layout of the electric power unit and battery for a lower center of gravity than seen on the 2018 model, and that Li-ion battery is reported to have 2.5x more capacity than before with only a 20 percent increase in weight.
As before, the setup runs a flywheel and a mechanical wet, multi-plate clutch but the power unit has been tweaked for better response and improved traction.
The only other key detail that Yamaha has shared at this point is a minimum ground clearance of 340 mm (13.4 in), though more information will likely be available when the TY-E 2.0 is displayed at the company booth at the 49th Tokyo Motorcycle Show from March 25. After that, the electric trials bike will be entered in select rounds of the 2022 Fédération Internationale de Motocyclisme Trial World Championship from June.
Source: Yamaha
A trials bike powered by an electric motor would pose huge problems of controllability, with the instant torque available. A clutch is essential.
At the Blackpool (UK) motorcycle show electrical component supplier Joseph Lucas (AKA "The Prince of Darkness" because of their somewhat unreliable lamps) had a stand with two trials bikes, a Greeves Scottish and a BSA C15T, fitted with car batteries and electric motors and a small trials section.
Control was basic, the twistgrip was connected to an on/off switch.
Things have come on quite a bit since then!