Not to be confused with the motor sprocket, this pinion goes on the secondary drive side of the reduction shaft. It’s a spare part to replace a used sprocket, same size as stock.

The shaft pinion’s role is to transmit torque coming from the the primary transmission to the wheel sprocket. As such, it undergoes huge forces at very high speed. You’d be amazed to see how fast the teeth wear out for high powered Sur Ron Light Bee.

Wear speed depends on so may factors that it’s impossible to indicate a replacement timeframe. Nevertheless, just have a look at it, if its teeth are rubbed, bent or dented, it’s time for a change!

Technical details