DHM Gen 2 149cc Big Bore Cylinder kit for 2022+ Honda GROM

DHM Gen 2 149cc Big Bore Cylinder kit for 2022+ Honda GROM

 

The Gen 2 big bore 149cc kit is ready to go!

Kit includes:

• 55mm Forged Piston with RK Ring kit
• 55mm Sleeved cylinder
• Base and head gasket set
• NGK Spark Plug

This kit provides a significant horsepower and torque increase across the entire rev range. Expect gains of 30% in the midrange over a bike with intake, exhaust and cam, and double the horsepower of a stock bike at 8500rpm. We recommend running it with our S1 camshaft along with an aRacer MiniX and AF2 combo for tuning. Or PV3 with Auto tune.

Install Notes:

• Two base gaskets included. Use both copper and paper gaskets for pump fuel, use only the copper gasket if you are running race fuel.
• An NGK CR9E spark plug must be used
• Ring gaps must be set during install, we recommend .011″ on the upper ring and .013″ on the lower ring
• 91 octane is the bare minimum, and 93 is preferred.
• Set aRacer spark advance timing to -6 across the entire table when using pump fuel. Spark angle can be adjusted during dyno tuning.
• Honda injector 16450-KZY-701 is the recommended injector for this kit.