Yamaha SZR660

Yamaha SZR660 is a sport bike with a 659 cc (40.2 cu in) single-cylinder engine, produced by Yamaha Motor Corporation from 1996 to 2001. It was built in Italy by the Italian Yamaha importer Belgarda. It shares its engine with Yamaha's XTZ660 Ténéré line of dual-purpose on/off-road motorcycles, but employs this engine within a Supermono package.

Yamaha SZR660

Manufacturer	Yamaha
Production	1996–2001
Class	Sport bike
Engine	659 cc (40.2 cu in) four-stroke, SOHC, liquid cooled, 5 valve, single
Dimensions	L: 2,040 mm (80 in) W: 740 mm (29 in) H: 1,140 mm (45 in)
Seat height	770 mm (30 in)
Weight	159 kg (351 lb) (dry)

The 660 engine incorporates a five-valve cylinder-head. There are three intake and two exhaust valves. The theory is that the smaller valves have a larger area at a lower weight than a four valve system and allow maximum intake flow and velocity.

A vacuum operated fuel pump is mounted on the bottom of the fuel tank to lift the contents of the tank to the twin carburetors. The fuel system incorporates one slide carb and one butterfly carb. These are operated sequentially by a manually adjustable system.