Koso 170cc 61mm Big Bore Kit – Honda Grom & Monkey (2014-2020)

Want to unleash all the power your Honda Grom can handle? Koso’s 170cc Big Bore Kit (MB623002) is the perfect addition for you! The kit includes a ceramic coated cylinder, 61mm forged piston, rings, pin, gasket kit and banjo bolts. Its compression ratio of 11.5 to 1 will allow you to still use premium pump gas and keep the reliability of a stock motor. Made from the best components available on the market, Koso’s 170cc big bore kit will amaze you! Also compatible with the Honda Monkey 125cc. Fits model years 2014 to 2020.

***Please Note: You may need to modify your engine case to accommodate the larger cylinder***

*Please note: Compatible with 2014-2021 Honda Grom

• Cylinder Displacement: 169.2cc
• Cylinder Material: Aluminum/Ceramic CoatedCylinder Overall Height: 90.5mm
• Piston Diameter: 61mm
• Piston Type: Forged
• Compression Ratio: 11.5 to 1

Honda Grom 125, Honda Monkey 125

This product is not intended for use on public roads or land.