Blue Line

Blue Line 4T Big Bore w/ Head (72cc, 69mm Valves): QMB139

SKU 1100-1515
Shipping calculated at checkout.

Complete 72cc Iron cylinder & head kit!!! This works with Chinese 50cc 4-stroke 139QMB engines with 69mm valves like Znen, Kymco, Wolf, Scoot Star, and some newer Tao Taos.

Pump up that weak engine to a respectable 72cc displacement, on a budget. This kit is not indended to make your scoot a screaming race-machine. It is intended to get you that extra power you need. (Most Chinese 50cc's only put down around 1.5hp to the ground.)

Increase the reliability & power of your scoot today!



Remove your valve from your scooter's head and meaure the full length of the valve stem. If your scooter has 64mm valves, you'll need the following 64mm big bore kit.

This product is not intended for use on public roads or land.

  • Same day shipping for orders placed before 2PM (CST) M-F
  • 30-day return period
  • Flat-rate shipping for orders shipped to the 48 Contiguous United States.
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