torque spring Polini +15% for Yamaha, MBK 125

These Polini counterpressure springs increase pressure by 15%, making them ideal for light tuning. When the level of tune increases, so too should the strength of the springs. Variator must be calibrated if springs are changed. Original Spring Loading: 45/31.5mm/kg Polini Spring Loading: 45/37mm/kg Spring Thickness: 4.1mm Spring Length: 115mm Inside Diameter: 53mm Number of Turns: 5