The ROK VLR is the perfect engine for the entry-level driver, the ROK VLR not only offers superior performance over its rivals with lower maintenance, but it also offers some great features like electric start. All at a cost racers can afford.The new ROK VLR engine was designed solely with club racers in mind, whether it’s a new racer getting into karting, or for those looking to move up from a four-cycle powerplant. Great for the racer that wants to update their current 100cc to a state-of-the-art engine package. The new ROK VLR engine comes complete ready to race minus the engine mount.The ROK VLR engine can be utilized in Junior VLR (ages 12-15), Senior VLR (ages 15+) and Masters VLR (ages 32+). TECHNICAL INFORMATION Measurement Tolerances Volume of cylinder: 98.53 cc 100cc MAX Original bore: 48.20 mm ±0.2 Theoretical maximum bore: 48.53 mm MAX Stroke: 54.00 mm ± 0.2 mm Cooling system: AIR-COOLED Number of carburation systems: 1 Number of transfer ports/ducts,cylinder/sump: 3 Number of exhaust ports/ducts: 1+2 (1 elliptical port plus 2 boosters) Shape of combustion chamber: Spherical with squish Length between axes of the Connecting rod: 102 mm ± 0.2 mm Minimum weight of connecting rod: 115 g MIN Volume of combustion chamber: 9.2 cc MIN Type of bearings and size Conrod big end bearing: 20x26x15, Conrod small end bearing: 14x18x17, Crankshaft bearings: 25x52x15OPENING ANGLES (all mesurement done with 0.20mm feeler gauge)Tolerances: Inlet 126° ± 2°, Exhaust 164° ± 2° LIST OF ACCESSORIES INCLUDED Carburetor Butterfly valve/24 mm Generator for battery Charging: On board Electric starter: On board Exhaust with flex: Exhaust with silencer MATERIAL Cylinder AL – SI ALLOY Connecting rod NI – CR – MO STEEL Crankshaft NI – CR – MO STEEL Head AL – SI ALLOY Liner IRON Crankcase AL – SI ALLOY Piston AL – SI ALLOY Piston Ring STEEL OR IRON
