IET Integrated Electric Transmission Motorcycle from SMRE Engineering

IET Integrated Electric Transmission motorcycle

Look at any electric motorcycle these days, whether TTXGP competitor or one of the first general purpose commuters and you'll notice one thing is missing, the shift lever. Electric motors have all of this torque available so you just twist the electric throttle and pour the electrons to the motor. Want to go faster? Spin the motor faster.

IET Integrated Electric Transmission motorcycle

SMRE Engineering of Italy, figured this was an inefficient way to do things, but also, the lack of transmission and shifting took some of the enjoyment out of the ride, so they built the IET System, an electric motor with a six speed mechanical transmission and clutch, a mechatronic motorcycle. Software can map the motor's performance characteristics for whatever you might need or want while allowing a smaller motor and battery pack than necessary without the transmission since multiple gears keeps the motor in the most efficient range. The smaller battery pack makes up for the additional weight of the transmission.

Software mapping can also simulate the deceleration of a standard engine during which the motor acting as a generator can recharge the batteries. Plans are to start with a pit bike and then advance to a Supermotard.

Those more familiar than I am with the design and engineering of electric motorcycles can comment on whether their reasoning is sound, but the fact that they've built it and are running the system successfully is a strong argument that it works. Even if it didn't add to the efficiency, the idea of shifting is so ingrained in many of us, that alone might make the whole thing worthwhile. I think it's a great idea.

source : http://thekneeslider.com/archives/2010/11/04/iet-integrated-electric-transmission-motorcycle-from-smre-engineering/