KTM 125 trumped F1 by running a KERS system on their 125 racer in Valencia last year. Seeing the rider made 13 places in 3 corners you can say it works a fair bit better than the late Brockie's polariser. It adds about 2kW or 3.5HP on the KTM, the system uses no batteries as with the car just some capacitors that can 'dump' stored energy fast. In short a belt is connected to the flywheel and to a electric motor, under braking the motor is driven by the flywheel charging the caps, then under power the motor turns the belt by power from the caps.That would have the KTM at almost 60HP from a 125 a-bloody-mazing