Changing the strength of your contrast spring can be vital to get your tuned engine to hold a consistent RPM keeping your engine on power for longer. Applying more pressure to the torque driver can help to reduce belt slip whilst forcing the engine to feel more responsive and often make more power.
Minarelli engines 3.8mm – PMP001 - £6.10
Piaggio engines 4.0mm – PMP005 - £6.10
