The Siba company produced starter generators based on DC motors under the designation DynaStarter from 1935; in 1959, Siba was taken over by Bosch and thus so was DynaStarter. The name Dynastarter is derived from the words ‘dynamo’ and ‘starter’. Their unique feature was – or rather still is – that they are directly mounted on the crankshaft with no other gearing. The starter generators were first used by DKW Mobile and then later by BMW in the Isetta, NSU Prinz, Goggomobil and many other vehicles.
One advantage of the generator was that it saved having a reverse gear in small cars with two-stroke motors, and the reason for this was very simple: two-stroke motors can run backwards if they are started in the opposite direction and this could be achieved simply by reversing the polarity of the starter motor. The DynaStarter is thus an interesting little piece of history that should be preserved.