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TBparts - Roller Rocker Race Head V2 88cc Big Bore Kit
Z50 CRF50 XR50 & Pit bikes w/ Mikuni VM26 Carb

Vital Information
On Sale $619.65
Part No TBW9115
Stock Level Check Stock
This item my be sold out. Click the Yellow Check Stock button above to send us email and we'll try to let you know when it become available.

We are all out of the standard aluminum head covers
We can offer you:
RED Billet covers Part No:TBW0852
Black Billet covers Part No:TBW0853

TB Roller Rocker Race Head V2 (52mm) Big bore kit.

Highest Performance Race head on the market with full parts support in stock.

Key Features:

  • Roller Rocker Arms exactly like the V2 head for the KLX110
  • 28.5mm intake Valve
  • 23.5mm Exhaust Valve
  • 5mm Valve Stem
  • 23mm Exhaust port
  • Matching High Compression Piston
  • Head kits include all hardware
  • 52mm piston with rings, pin, & clips.
  • 52mm Aluminum Cylinder
  • High performance race camshaft (for the V2 Race Head only)
  • Head gasket kit.
  • Mikuni VM26 Carb kit
We Recommend using premium fuel

  • 2 Size clutch tool - WHS-2274
  • High volume oil pump - TBW0226-12V (TBW0225-6V for 1981 or before models)
  • High speed 2mm drill bit - TRC-5526
  • TBparts oil cooler for V2 heads - TBW9187
  • Sta-bil fuel stabilizer - W-57-1109


  • Z50 - 1988-present
  • CRF50 - 1988-present
  • XR50 - 1988-present

 Kit Includes:

  • TBW0750 - V2 Race head
  • TBW0755 - V2 Head bolt kit
  • TBW0752 - Camshaft V2
  • TBW0754 - V2 Head cover set
  • TBW0753 - Piston
  • TBW0859 - Gasket Set
  • TBW0156 - Cylinder
  • TBW0301 - Cable
  • TBW0433 - Intake Kit
  • TBW0399 - Carburetor
  • TBW0413 - Air filter

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).

See the Performance Info section for additional information on our performance parts.

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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.


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