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170cc Big Bore V4 Complete Head Kit - For Honda Grom & Monkey

Retail Price: $749.95
You save: $74.99  (10%)
Our Price: $674.96

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  • Model: MC623000
  • Shipping Weight: 10.5lbs
  • 28 Units in Stock
  • Manufactured by: KOSO


For Honda Grom & Monkey

  • Camshaft Torque: 1.71 Hp: 26.26 *measured without air filter & no noise reduction plug
  • Compression ratio: 12.3:1
  • Cylinder head titration: 13.4 cc
  • Cylinder height: 64.2 mm
  • Gasket thickness: Upper: 0.25 mm
    Bottom: 0.5 mm
  • Piston compression: height: 19.5 mm
  • Squish: 1mm
  • Valve / Tappet clearance: IN: 0.10 mm EX: 0.17 mm
  • Volume: 169.21cc

Requires the use of Iradium spark plug: NGK-ER9EHIX (part NGK-ER9EH) or Denso # IY27, IY29 or IY31

  • Unique four-valve design increases air flow and performance
  • Provides more power and torque
  • Ideal engine part to complete Koso's Big Bore kit
  • Features a forged piston, stainless steel 24mm intake valves and 20mm exhaust valves
Our Koso 4V Head Kit is the ideal engine part to complete the Koso Honda Grom Big Bore kit. Because of its unique 4 valve design, the air flow and performance are increased. This new designed head is the perfect addition for those who desire more power and torque. The 4 Valve Head Kit features a forged piston, stainless steel 24 mm intake valves and 20 mm exhaust valves.

This part fits the following

MotorcycleHondaGrom MSX1252014124.901
MotorcycleHondaGrom MSX1252015124.901
MotorcycleHondaGrom MSX1252016124.901
MotorcycleHondaGrom MSX1252017124.901
MotorcycleHondaGrom MSX1252018124.901
MotorcycleHondaGrom MSX1252019124.901
MotorcycleHondaGrom MSX1252020124.901
MotorcycleHondaGrom MSX125 ABS2019124.91
MotorcycleHondaGrom MSX125 ABS2020124.91
MotorcycleHondaMonkey ABS20191251
MotorcycleHondaMonkey ABS20201251

This product was added to our catalog on Friday 18 September, 2020.


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