YX 140 / 160 Pit Bike Race Gearbox 13/34, 17/29, 17/23, 19/21

This is a new set. Longer 1st & 2nd gear. Makes 1st nd 2nd more useable with higher gearing. Ratio is: 1st: 13/34 2nd: 17/29 3rd: 17/23 4th: 19/21 Will fit in all YX140, YX160 and DETROIT 170. Will NOT fit Z155 or Lifan models.