80cc qmb139 transmission gears 8% increase

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  • $93.00
  • Regular price $105.00

Jasil Top Racing 17/51 Gear Set for 50cc QMB139 GY50 4-Stroke Engines. +8% Gear Ratio for increased top speed. It is recommended this gear set be used after installing a big bore cylinder kit. A stock engine will not have enough power to make use of a taller gear set.

Made in Portugal! No press required like common tall gear sets, drop in and go!