DHM High Compression Stock Bore Piston for 2022+ Honda Grom/ Monkey (PRE ORDER)

DH Motoring Stock Bore Racing Piston (2022+ Grom / Monkey) We've now produced the first high compression stock bore piston for the new 2022 Grom/Monkey. We took our development experience from the previous generation Grom and CRF110 and applied it to the all new Grom engine and have come up with a lightweight, high compression piston that still utilizes the OEM 12mm pin size.

• ~13:1 compression 50mm stock bore piston
• Larger ring and skirt oiling holes than other pistons on the market
• Larger oil spring to increase oil volume between the oiling rings
• OEM sized skirt area to maintain reliability
• Racing piston ring kit with pins and circlips
• Valve reliefs that clear valves up to 27/22 cylinder head valves
• Includes a new base gasket and head gasket
• Includes a NGK CR9E spark plug that is required
• Requires at least 91 octane fuel
• Requires ECU Flash or other Engine Management.

Increasing the compression ratio on the stock bore significantly increases the throttle response and overall power of the engine. In comparison to the stock piston, you can expect more low, mid and top end power while maintaining the use of your stock cylinder. We've designed this piston to be as close to the stock weight as possible without sacrificing any structural integrity. It can clear big valve head with 27/22 valve diameters and it will drop right in to your OEM cylinder. You will need either an ECU flash or some sort of fuel controller for this to run properly.