OK, it's not a bike, but it is electric... Bubble cars are back!

[MikelBikel]

It's a motorbike, yes, but principle could work for electric trike? Will chain flex enough?

 

[Waspy]

Coming back to three wheelers and reverse gear.
I seem to remember a mate of mine turning up on christmas day (I was about 16) in an old Bond. Starting it meant lifting the bonnet and kick starting the engine, think it was a 250 villiers two stroke single. The engine was actually mounted on the bogey with the front wheel, so the chain drive was straight to the wheel. The engine turned with the wheel and you got reverse by actually turning the whole assembly through 180 degrees.
It was noisy, smelly, cold and slow but we didn't get wet cruising around on christmas day. What a hoot.

It was called a Bond Minicar, a mate of mine had one for a while in the early 1970s.

His had a 250cc twin cylinder Villiers engine, with the kickstart under the bonnet.

These air-cooled engines were developed principally as motorcycle units and therefore had no reverse gear. However, this was a minimal inconvenience, because the engine, gearbox and front wheel were mounted as a single unit and could be turned by the steering wheel up to 90 degrees either side of the straight-ahead position, enabling the car to turn within its own length.

A method of reversing the car was offered on later models via a reversible Dynastart unit. The Dynastart unit, which doubled as both starter motor and dynamo on these models incorporated a built-in reversing solenoid switch. After stopping the engine and operating this switch the Dynastart, and consequently the engine, would rotate in the opposite direction.

They were made in Preston, Lancashire, between 1949 and 1966.