1962/2017 Matchless G50 496cc
Type: Air-cooled sohc single Capacity: 496cc Bore x stroke: 90 x 78mm Compression ratio: 11:1 (variable) Valve sizes: 2in (51mm) inlet, 15 /8in (41mm) exhaust Valve clearances: 0.08in inlet, 0.012in exhaust Valve timing*: Inlet opens 55° BTDC, closes 68° ABDC; exhaust opens 78° BBDC, closes 45° ATDC Carburation: 1½in Amal Grand Prix Ignition: electronic magneto Spark timing*: 34° before TDC Primary drive: chain Lubrication: dry sump Final drive: chain Weight: 37.5kg (82½lb) Power output: 51bhp at 7200rpm *Engine builders may not use these factory recommended figures