Technical questions?

If you need information about batteries you can find a document called bases of the battery technology in the download section of our website. 

What choice, 24V, 36V or 48V?

After some time going up the hill a motor 36V, the controller and the batteries do not warm up much. At least 50% less than with a 24V motor. With a 48V version even cables do not warm up.

Less warming = less energy loss

Example, a battery of 12AH:

24Vx12A = 288 WH

36Vx12A = 432 WH

48Vx12A = 576 WH 

More tension    

  • More reserve and more power
  • Up to 120% more autonomy
  • Less wear batteries and components.

For the full engine power (250W at 36V) power from the battery must be in compliance.

250W: 24 V = 10.41 A

250W: 36 V = 6.94 A

250W: 48 V = 5.20 A

Less energy for the same power!

For a discharge current of 15A cables must be at least 2.5 mm in diameter. Connections must be good. The most common reason for failure of components is an overload of heat.  

Engine in the front or rear wheel?

Basically, the engine type and the modes of action are the same if they are incorporated in the front or rear wheel. The different positions of the engine, however, have advantages and disadvantages. The hub motor as a front-wheel drive offers many advantages:

  • It is ideally suited for converting a bicycle. The conversion of an existing bike to an electric bike is easy. The main work is to replace the front wheel.  
  • Weight distribution on both wheels is better balanced than in other arrangements.
  • No handicap when changing tires. The front wheel can be changed as usual. The cable connection is usually via contact form.
  • If the bike is used as Pedelec it becomes an all-wheel drive. The front motor acting consistently (if not a torque control) reduces the fluctuations of the saddle and allows a relatively balanced handling.
  • The load on the front wheel (even with the engine) is lower than on the rear. Slippage of the front wheel is more important than on the rear wheel. This means that the propulsion power is lower than an engine in the rear wheel.
  • Motor on the front wheel is not suitable for strong gradients. Even if the engine has more torque. This only increases the slip of the front wheel, especially on unpaved roads.
  • Gears of the cycle (in the hub or derailleur), everything can be reused. Especially the elderly are used to a coaster brake. This system can remain. 

 The motor on the rear wheel also has its advantages. Often there is a direct drive: 

  • Suitable for mountainous terrain. At a steep climb the load increases on the rear wheel (the front wheel is relieved) and reduces the risk of slipping. The traction performance is better if the engine on the front wheel.
  • As the battery is usually located behind, there are shorter power cables.
  • The distribution of the weight is on the back wheel. This does not improve the behaviour of the bike.
  • Only shifting via chain and derailleur is possible.
  • Coaster brake is not possible.
  • The change of the rear wheel is more difficult than of the front wheel.  

Central motor  



The concentration of components in the centre of the bike is ideal in terms of weight distribution. The very low centre of gravity is improving the behaviour of the bike. The existing chainline of the cycle must be deviated over the pinion of the motor. This avoids an additional chain as with our system. As the chain must be deviated there is a strong deformation of the chain. The chain will wear faster and the lifetime is only about half of a normal bicycle where the deviation of the chain is only in one direction. The wiring is extremely short. The weight of the unit without battery is about 4 kg (more than a modern hub engine). The use of a coaster brake is not possible and would be difficult to achieve. However, all types of gear, except a front derailleur can be used (rear derailleur and gears in the hub). The front and rear wheels remain unchanged. The engine can only be used with a specially designed. A kit for converting a bicycle is not available. 

Engine weight: approx. 4 kg

Rated Power: 250W or 350W 



More or less the same. No additional deflection of the chain.

Engine weight: approx. 4 kg 

Rated Power: 250W or 350W


Sources: E-Bike-Technik Teja and Eberhard Müller (available in our shop, but only in German)

Photos: Bosch et Panasonic