Description
Torque Spring Stage6, Piagggio LEADER / QUASAR 125-300cc 4-stroke, to adjust drive belt tension and shifting characteristics. The springs are made of high carbon high silicon steel and tempered for added strength.
Pressure on the belt is one of the key factors in a transmission. If the spring is too soft, the belt might slip and rub against the side of the pulley, and your engine revs up but does not accelerate properly. If the spring is too hard, the belt will be kept from moving and the engine cannot reach maximum rpm. In both cases, you'll lose power to the rear wheel. The spring should always match your set-up - harder does not necessarily mean better!
Contra spring
The contra spring, or torque spring is part of all scooters and mopeds with CVT transmissions.
function of torque spring
The contra spring is located between the torque driver and the clutch. As soon as you accelerate and the engine revs up, the spring is released by centrifugal force. This causes the torque drive to open, which in turn causes the V-belt to move outward on the CVT front pulley. The transmission ratio changes in favor of higherspeed. When the scooter slows down and the engine speed is reduced, the torque spring is compressed again and the V-belt returns to a lower position on the front pulley.
soft or hard contra spring?
The choice of torque spring depends on different engine components, you need to find the right balance here.
- A spring that is too hard cannot fully expand. Acceleration is improved, but the V-belt cannot move outward to the maxi and top speed will be lowered.
- A spring that is too soft will relax too quickly, affecting the pull of your scooter.
Tip: To determine whether the V-belt can move to its maximum achievable position, you can mark the maximum position with a felt-tip pen on the CVT. If the mark disappears, this indicates that the belt actually moves up to the max position, i.e. the spring is not too hard.