

DROWsports
DROWsports Honda Grom/Monkey 198cc 4 Valve Performance Cylinder Kit
DROWsports Honda Grom/Monkey 198cc 4 Valve Performance Cylinder Kit
1860 Obispo Avenue
1860 Obispo Avenue
C
Signal Hill CA 90755
United States
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NEW!! DROWsports LS 198cc 4v Head Big Bore Cylinder Complete Kit was designed for the Honda Grom and Monkey. We wanted to develop an affordable larger displacement cylinder and piston kit for KOSO 4 Valve Head. The design we've come up with utilizes that and has similar features to the 170cc piston and cylinder but offering more attention to detail. The KOSO 170 is great and we've loved pushing that kit to its limits, but we wanted a little more displacement and a few key features.
Cylinder & Piston
DROWsports LS 4v 198cc Big Bore Cylinder & Piston is an upgrade to the 170cc cylinder and piston kit. This utilizes our very own 63mm 4 valve forged piston. Although forged and machined, these pistons are lightweight and our 181cc piston weighs only a couple of grams more than the 170cc piston. These are all CNC machined for tight tolerances and include a special frictionless coating. This helps it push 11.5:1 compression ratio for great performance! The machined radius edges and special accumulator groove are some of the extra detailed features we were looking for. We wanted to stick with the 4 valve design because of the performance capabilities and options that it is capable of making.
Cylinder Head
The KOSO 4 Valve Cylinder Head was a perfect pick to work with. The head already comes pre-assembled with a cam, valves, rockers, and seals installed. It head uses 24 mm intake valves and 21 mm exhaust valves allowing it to breathe much better. This is exactly what we needed for our 198cc because having a 68mm piston it is definitely needed.
Engine Building
As enthusiasts, we pride ourselves on building high-performance engines that are designed reliable and consistent. We offer our experience of engine building as an option to assemble the motor. This includes all the options that we do to our personal bikes like WPC treatment, race porting and polish and crankshaft balancing. WPC treatment to engine components offers reduced surface friction making it ideal for piston treatment.
Main Kit Includes
- DROWsports 198cc Ceramic Cylinder
- DROWsports 66mm 4 Valve Forged Piston
- KOSO 4 Valve Cylinder Head Assembly
- KOSO Camshaft
- KOSO Intake Manifold
- Iridium Spark Plug
- Performance Break-In Oil