Honda’s new-generation V-Twin engines offer improved fuel efficiency, emissions performance, versatility, and quiet operation. Featuring six models, the engine line consists of the GX630, GX660, GX690, GXV630, GXV660, and GXV690 engines in both horizontal and vertical shaft configurations. Applications include utility vehicles, zero-turn radius mowers, garden tractors, trenchers, stump grinders, chippers/shredders, concrete saws, vibratory rollers, and ride-on cement trowels. The 36-blade, low-noise resin cooling fan improves cooling efficiencies. A hemispherical combustion chamber design, higher compression ratio, increased displacement, and steel connecting rods contribute to the engine’s high efficiency and low noise and vibration. Additionally, integrated cylinder and head eliminate the need for a head gasket, which results in increased cooling and higher levels of reliability. Advanced combustion chamber design and digital capacitive discharge ignition with variable ignition timing, as well as twin barrel inner-vent carburetion, contribute to high fuel efficiency. The engines will meet the 2011 U.S. EPA exhaust emissions regulations without the use of a catalyst.