When it comes to an engine that is suitable for use in the motorcycle did the choice fell on a direct current motor (DC). The main reason is because it can run the variable speed, high efficiency and high power/weight ratio. This type of engine also has a very good bottom drag in relation to, for example, brushless motors.
Since Roskva to compete against conventional motorcycles, the motor power be around 40 to 50 hp. To find the engine manufacturer must not only think about power, but also quality. We have therefore been in contact with a number of European manufacturers. The choice fell on Lynch Motor Company in England which has a number of different engines for different applications. The engine we chose to Roskva is a D135RAGS that is a part of the LEM200 series.
In Roskva we have two such engines, which will gives us a total output of 92 horsepower and 80 Nm. This will give Roskva more than enough power to compete with other similar bikes.
The brains of the engine, the controller, must also be selected. It must be able to handle enough voltage and current when the engine is running at full power. Here, the choice fell on Kelly motor controller from China. Each engine will have their own controller which is controlled via a standard twist handle. These speed controllers can handle a voltage of 120 volts and 600 amps at peak.