?? Complete Rear Clutch For GY6 50cc 4-Stroke 139QMB Engines ?? 22 Splines Inside The Clutch Drum/Bell ?? Outer Diameter of drum: 115mm ?? Inner Diameter of drum: 106mm ?? Pulley Diameter: 118mm
  Outer Diameter (pulley): 118mm Outer Diameter (clutch bell): 115mm Inner Diameter (clutch bell): 107mm Inner Diameter (clutch): 12mm Outer Diameter (shoes): 104mm Clutch Bell Inner Diameter (splines peak to peak): 11mm Number of Splines (clutch bell): 22