Minarelli clutch springs / Start 3/5 white/black/blue Motoforce Racing

For the perfect adjustment of a tuned engine, a stiffer contrast spring is required.
The contrast spring is located behind the clutch, applying counterpressure to the pulley and therefore to the belt. If the spring is too soft, the belt slips and the bike does not accelerate or does not accelerate properly.
Keep in mind that when installing a stiffer spring, you may also need to change the variator rollers for heavier or lighter ones.
A great advantage of contrast springs is that each spring has its stiffness marked on the surface.

Contrast springs (set of 3) MFR, for 50cc Minarelli / CPI scooters and Derbi Start 3/5 models!