BMW's New Single

The G 310 R is BMW’s world bike. It is designed to run on most available fuel qualities, get great fuel economy, and meet all emission standards and local requirements while establishing a beachhead for BMW in the sub-500 cc. class.
Powered by a new 313 cc. single-cylinder engine, the 349 lb. G 310 R produces 34 hp at 9,500 rpm and 21 lb.-ft. of torque at 7,500. The liquid-cooled, twin cam engine has a bore of 80 mm., stroke of 62.1 mm., and a relatively moderate 10.6:1 compression ratio. The single cylinder is laid back 180 degrees with the intake tract positioned at the front and facing the direction of travel. This leaves a lot of room for a generous intake silencer that is positioned directly behind the steering head and fuel tank. The valve gear is similar to that found on the S 1000 RR, and features friction minimizing Diamond Like Carbon-coated engine components and a Nikasil cylinder liner. DLC coating also is used on the piston pin to eliminate the need for a bearing in this area. To reduce vibration, there is a counterrotating balance chart located directly in front of the crankshaft, while engine-out emissions are handled by a closed-loop catalytic converter and secondary air system. The engine mates to a six-speed gearbox that drives the rear wheel through an O-ring chain.