Discontinued product, for reference only.

*Does not fit 2022+ models

This complete top‑kit is the perfect add‑on for all horsepower enthusiast looking for performance ! It includes : a 170cc ceramic coated cylinder, forged piston, performance camshaft, bearing, rocker arms, 4 valve cylinder head, intake manifold, gaskets, and more. All parts are made from High‑quality components for reliability and durability that allow you to put your mind at ease and ride with confidence!

WARNING

THIS IS AN AFTERMARKET PART BUILT FOR RACING PURPOSES ONLY. KOSO IS NOT RESPONSIBLE FOR ANY DAMAGES CAUSED TO THE PARTS, VEHICLE, OR TO YOURSELF AND OTHERS. ENGINE PARTS ARE NOT UNDER WARRANTY NOR IS COLLATERAL DAMAGE OR COST OF LABOR, IN CASES OF MALFUNCTION.

https://www.youtube.com/watch?v=pcVJlqdgays

 Specifications

For more important tips, notes, list of parts and other modification required,  see Honda GROM® FAQ page or download our Honda GROM® Caution PDF.

Instructions

  Download PDF
When using 170cc big bore kit and 4 valves head, customer must change or add the following parts:
Parts
Description
Mandatory
Suggested
Mini 3 - Air/Fuel ratio meter | Honda GROM
X
Mini 3 - Cylinder head temperature | Honda GROM
X
High flow injector | Honda GROM
X
Injector adaptor kit | Honda GROM
X
Hurricane racing air filter fits GROM only
X
Hurricane racing air filter fits MONKEY only
X
Connecting tube | fits GROM only
X
Intake tube | fits GROM only
X
34mm Throttle body | Honda GROM
X
Clutch kit (discs + springs) | Honda GROM
X
Enhanced lifter plate black | Honda GROM
X
Ignition coil | GROM
X
High flow oil pump | Honda GROM
X
Chain tensioner | Honda GROM
X
NGK Spark plug | Honda GROM
X
ECU Modification
X
Addition of a fuel control box
X
Proper exhaust system must be used to prevent re-flow pressure and heat
X
Other

Instructions

  Download PDF
When using 170cc big bore kit and 4 valves head, customer must change or add the following parts:
* M = Mandatory | S= Suggested
Parts
Description
Mini 3 - Air/Fuel ratio meter | Honda GROM
S
Mini 3 - Cylinder head temperature | Honda GROM
S
High flow injector | Honda GROM
M
Injector adaptor kit | Honda GROM
M
Hurricane racing air filter fits GROM only
M
Hurricane racing air filter fits MONKEY only
M
Connecting tube | fits GROM only
M
Intake tube | fits GROM only
M
34mm Throttle body | Honda GROM
M
Clutch kit (discs + springs) | Honda GROM
S
Enhanced lifter plate black | Honda GROM
S
Ignition coil | GROM
S
High flow oil pump | Honda GROM
M
Chain tensioner | Honda GROM
S
NGK Spark plug | Honda GROM
M
ECU Modification
M
Addition of a fuel control box
M
Proper exhaust system must be used to prevent re-flow pressure and heat
M
Other
 

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SKU MB623003
Brand Koso
Product Specifications