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TBParts 88cc Big Bore Kit, Race Cam and 20mm Carb Kit
for Z50 CRF50 XR50 88-Present

Vital Information
Part No TBW0930
Stock Level 4 Left

TBParts Race Cam, 88cc Big Bore kit, and 20mm Carburetor Performance Kit

´╗┐Key Features:
  • Lightweight aluminum cylinder with steel sleeve
  • Cast in mounts on cylinder for aftermarket skid plates
  • Oversized cooling fins on cylinder for efficient heat dissipation
  • TBW0190 52mm piston with rings, pin, & clips
  • Head gasket kit
  • Main jet kit
  • High performance race camshaft aggressive lift and duration without sacrificing low end torque
  • 20mm Performance carb assembly. Includes: 20mm carb, intake, heatstop, gaskets, mounting hardware/wrench, air filter throttle cable 

We recommend purchasing a high volume oil pump kit part number TBW0226

Installation Note:
It will save a lot of time and effort if the oil pump is installed while installing the bore kit (requires cylinder removal).
There are no installation instructions, but if you can replace your piston, you can install this kit. If you don't have any experience working on your engine, we highly recommend purchasing the shop manual for your bike available in our store. 
The parts are installed in the same manner as the OEM parts.

Exceeds OEM Standard equipment


  • Honda Z50 1988-1999
  • Honda XR50 All Years
  • Honda CRF50 All Years

Kit Includes:

  • TBW0190 Piston
  • TBW0206 Gasket
  • TBW0156 Cylinder
  • TBW0125 Carb
  • TBW0263 Intake Manifold
  • TBW0301 Throttle cable
  • TBW0398 Air Filter
  • TBW0189 CamShaft
  • TBW0294 Jet kit

A Great Upgrade Kit Stock Head! Not for use with the TB V1 or V2 Race Head.

(1 Reviews)

Since 2004, every purchase from TBolt USA includes access to technical support from our staff of experts and our online Pit Bike Technical Info Database!

We have all necessary support parts on hand.

Most orders ship same, or next business day, unless otherwise noted above.