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About Koso North America 4V Head Kit w/ 170cc Big Bore Kit

Koso North America 4V Head Kit w/ 170cc Big Bore Kit

  • Ideal engine part to complete Kosos big bore kit
  • Unique four-valve design increases air flow and performance
  • Provides more power and torque
  • Features a forged piston, stainless steel 24mm intake valves and 20mm exhaust valves.

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