Heinzmann are a German motor manufacturer who make a range of very reliable motor systems – I’ve been using them for over 15 years. There’s two basic types, the Classic (below) with brushed motor and a twist throttle, and the DirectDrive brushless motors (above) with a handlebar LCD display unit. The kits can be e-bike (throttle only) or Pedelec (with pedal sensor too). Both motor types come in front or rear wheel versions, so can be fitted to almost any bike or trike. Classic motors have more torque, especially at low speed, the DirectDrive motors are effectively silent.
All the kits use LiIon batteries, in a few different sizes. The DirectDrive battery slides into a custom rack which holds the controller, the battery is removable in seconds for charging.
The DirectDrive’s handlebar LCD unit controls power, and also allows regeneration – down a big hill, the motor can turn into a generator to put some power back into the battery.
The Classic kits have a battery that fits in a pannier on the side of the rear rack. This means you can, if you want, carry two batteries to double the range.
The Classic kits also have a motorbike-style twist throttle on the handlebars – this throttle gives you direct control of the motor speed. It’s also possible to get the Classic kits with a pedal sensor – these kits still have a throttle, but the throttle isn’t enabled unless you are pedalling.
I can build the hub into a wheel for you, just tell me what size you need.