Koso 4V Cylinder Head Kit - Honda Grom & Monkey (128-16)

The Koso 4V Cylinder Head kit for the Honda Grom and Honda Monkey is the ideal engine part to complete the Koso Big Bore kit. Because of its unique 4 valve design, the air flow and performance are increased. This newly designed head is the perfect addition for those who desire more power and torque. The 4 Valve Cylinder Head Kit features a forged piston, stainless steel 24mm intake valves and 20mm exhaust valves. Feel the speed!


*Please note: Compatible with 2014-2021 Honda Grom

• Vendor Part Number: MC623000
• Cylinder Head Height: 14.2mm
• Upper Gasket Thickness: 0.25mm
• Piston Height: 19.5mm
• Cylinder Displacement: 169.21cc
• Squish: 1mm
• Cylinder Head Titration: 13.4cc
• Valve Clearance IN : 10mm, EX : 10mm
• Spark Plug Type NGK-5869ER9EH
• Camshaft Angle: 260
• Torque (max): 1.71
• Horsepower (max): 26.26