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Koso 4 Valve Cylinder Head Honda Grom / Monkey 2014-2020

$749.95
Fast Lane
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This product is legal in California only for racing vehicles which may never be used, registered or licensed for use upon a highway.

Koso 4 Valve Cylinder Head Honda Grom / Monkey

Complete the finishing touches of Koso's Big Bore Kit with this 4 Valve Cylinder Head. The unique four-valve design increases air flow and performance, providing your mini bike with more power and torque. 

Features:

  • 4 Valve head
  • Increased airflow and performance
  • Stainless steel 24mm intake valves
  • Stainless steel 20mm exhaust valves

Specifications:

  • Cylinder height: 64.2mm
  • Upper gasket thickness: 0.25mm
  • Bottom gasket thickness: 0.5mm
  • Volume: 169.21cc
  • Squish: 1mm
  • Cylinder head titration: 13.4cc
  • Compression ratio: 12.3:1
  • Valve/tappet clearance: IN: 0.10mm EX: 0.17mm

Note: Requires use of iridium spark plugs. This is an aftermarket part built for racing purposes only. Koso is not responsible for any damages caused to the parts, vehicle or to yourself and others. Engine parts are not under warranty nor is collateral damage or cost of labor in cases of malfunction.

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Please review this product's fitment notes & exceptions prior to purchase: Add to Cart

This product is vehicle specific. Click here to select your vehicle to ensure fitment.

Fitment Notes & Exceptions

Note: This is an aftermarket part built for racing purposes only. Koso is not responsible for any damages caused to the parts, vehicle or to yourself and others. Engine parts are not under warranty nor is collateral damage or cost of labor in cases of malfunction.

This Product Fits:


Honda
Grom MSX125 2014-2020
Grom MSX125 ABS 2019, 2020
Monkey 2019, 2020
Monkey ABS 2019, 2020
Product Style Item # Store SKU Manufacturer Product # Availability
Product Style Koso 4 Valve Cylinder Head Honda Grom / Monkey 2014-2020 Item # 1246455 Store SKU Manufacturer Product # MC623000 Availability Available: Ships in 1-2 business days
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