OS Max OSM13646

This is the O.S. Max 21VG (P) ES Electric Start, Rear Exhaust Monster Truck and Buggy Engine with the 21F Slide Valve Carburetor. Excellent mid-range power for 1/8 scale buggies and trucks to compete in ROAR sanctioned events. Preinstalled E.S. Starter backplate is designed to use the Duratrax Kwik-Pit Super Start for the HPI Savage or the HPI Roto Starter System (HPIP8711) Advanced Bi-Metallic Liner (ABL) cylinder liner construction This process uses a double layer of plating material rather than one thick layer. This helps the metal bond to the cylinder and is more durable. Also, the plating process is more consistent, resulting in a more precise fit between piston and sleeve for better compression and longer life. Machined aluminum piston, 3-port cylinder liner and double bushed knife edge connecting rod 21F two needle slide valve carburetor with insulated sleeve to prevent fuel vaporization SG (pilot) type one-piece crankshaft Two year limited warranty through manufacturer O.S. Max 21VG (P) ES Electric Start Monster and Buggy Truck Engine, 21F carb, illustrated manual, exhaust manifold seal, #8 glow plug, and preinstalled E.S. Starter backplate Duratrax Kwik-Pit Super Start System or the HPI Savage Roto Starter System (HPIP8711) Car blend nitromethane fuel with 10-30% nitromethane content, 16% nitro content recommended as starting point Most of the fuels we carry meet or exceed the lubricant content required for optimum performance and maximum engine life. In the past, the conventional lubricant content used in fuel was 18%. But with new advanced technologies, fuels like Red Alert and O'Donnell for example, have a better quality of lubricants even though the percentages of lubricant content are lower. These high-tech lubricants provide exceptional cooling and protection. Displacement: 0.211 cu in (3.46cc) Bore: 0.654" (16.6mm) Stroke: 0.63" (16.0mm) Practical RPM: 3,000-36,000 Power Output: 2.0 ps/30,000 RPM Weight: 15.27oz (433g) Crankshaft Size: 1/4-28 Factory Needle Valve Setting: 2.5 turns open from closed position Mixture Control Valve Setting: Adjust so that carb is approximately 1mm open at idle Metering Needle Valve Setting: Flush with the ball link body Distance Between Mounting Holes Same Side: 21mm (.83") Distance Between Mounting Holes Opposite Side: 37mm (1.5") Height Bottom of Mounting Tabs to Top of Cylinder Head: 87.4mm (3.4") Width of Mounting Tabs: 45mm (1.8") Width of Crankcase Below Mounting Ears: 30.8mm (1.2") Distance from Front Bearing to end of Crankshaft: 29.5mm (1.2") Distance from Center of Engine to Front Bearing: 44mm (1.7") Distance from Center of Engine to Backplate: 21.3mm (.84") Some notes on Slide Valve and Rotary Carburetors: Rotary Carbs offer a larger response in the middle of the power band. This works well for off-road applications when throttle response must be varied. Slide Valve Carbs provide greater response at the beginning and end of the power band. This works well for on-road and racing applications for fast take-offs and high speed. jxs 8/05/09 ir/jxs &