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TB Parts

TB Race Head, 88cc Bore & 20mm Carb Kit - Z50 K1-81 Models TBW0939

  • Sale
  • $ 394.95


Race Head, 88cc Big Bore kit, and 20mm Carburetor Performance Kit:
Z50 K1-81 Models

This Race Head has been updated for even more performance!  It now has 25/22mm valves with better porting/flow.  We also kept the combustion chamber the same size and changed the angle of the valves slightly. This will really wake up your stock engine and is comparable in power to the much larger Chinese 124cc engines!!!

Includes the following:
NEW! - Main jet kit is now included for FREE! 
Lightweight aluminum cylinder with steel sleeve
- Cast in mounts on cylinder for aftermarket skid plates
- Oversized cooling fins on cylinder for efficient heat dissipation
- 52mm high compression piston with rings, pin, & clips
- Head gasket kit
- High performance race camshaft and Honda cam sprocket
- Race Head – Larger valves (now 25/22mm) and better flow for increased performance. Also has bigger cooling fins. Includes all necessary parts and comes assembled!
- The exhaust valve has been upgraded to stainless steel (21-4N material).
- 20mm Performance carb assembly. Includes: 20mm carb, intake, heat-stop, gaskets, mounting hardware/wrench, long adjustable throttle cable, and a air filter. (Cable does not work with older slide style throttles. You must use a newer CR style throttle which we sell in our store.

We recommend purchasing a high volume oil pump kit, and installing it while installing the bore kit (requires cylinder removal).