KOSO Performance 170cc 4V Big Bore Kit (MB623003)
Fits ’13-’20 Honda GROM / GROM SF – PREMIUM GAS
‘MUST Use with Premium Gas
Requires a Fuel Controller & A/F Monitor (sold Separately) for Proper fueling.
Its Highly recommended to run a 16t or 17t Front Sprocket with this BBK
To keep the revs in the Power Band
• 170cc ceramic coated cylinder
• forged piston
• performance camshaft
• camshaft bearing
• rocker arms
• 4 valve cylinder head
• intake manifold & gaskets
Requires a Fuel Controller & A/F Monitor (sold Separately) for Proper fueling see also Below Recommended Parts
- NGK ER9EH
- PCX150 Injector
- KOSO 34mm Throttle Body
- ARacer RCmini 5 Engine Management ECU Honda Grom Monkey 125cc (All Years )
- ARacer AF1 for Auto Tune
- ARacer 1 to 2 Splitter or 1 to 4 Cable to add components
- Koso Cam Chain Tensioner
- Koso High Flow Oil Pump
- NCY Decompression Tube
** This BBK uses a smaller 8mm Spark Plug, we highly recommend adding to your order.
** Kit should be installed by a certified mechanic to ensure proper function. Improper installation could result in catastrophic engine failure.
** Highly Recommended To install Temp. Gauge and A/F Monitor to ensure proper running Temperatures and Add Longevity to the Motor.
The product that you are purchasing is designed and intended for closed course competition use only and is labeled as such, i.e. Yoshimura “RACE SERIES.” Yoshimura RACE SERIES , Carburetors, Intakes, Exhaust, or any other performance products are neither designed nor intended for use on PUBLIC ROADS or LAND. Such use is prohibited by Federal and State regulations. By Placing order and agreeing to the Terms and Conditions at CHECK OUT you acknowledge that the item being purchased is for racing only and this vehicle will never be used on public roads or land.