|Manufacturer||Kawasaki Motorcycle & Engine Company|
|Parent company||Kawasaki Heavy Industries|
|Engine||652 cc (39.8 cu in) inline four|
|Bore / stroke||62 mm × 54 mm (2.4 in × 2.1 in)|
|Top speed||115 mph (185 km/h)|
|Power||62 hp (46 kW) @ 8,500 rpm (claimed)|
|Torque||41 lb⋅ft (56 N⋅m) @ 7,000 rpm (claimed)|
|Ignition type||points, then CDI|
|Transmission||5-speed, chain final drive|
|Frame type||double cradle frame|
|Suspension||Front:36 mm telescopic forks |
Rear: twin rear shocks
|Brakes||Front: single or twin 275 mm (10.8 in) discs |
Rear: 180 mm (7.1 in) drum or disc
|Wheelbase||1,420 mm (55.9 in)|
|Weight||465 lb (211 kg)1976-1977(dry)|
493 lb (224 kg)1978-1981 (dry)
485 lb (220 kg) (wet)
|Fuel capacity||16.8 L (3.7 imp gal; 4.4 US gal)|
The Kawasaki Z650 (known as KZ650 in North America) was a 652 cc (39.8 cu in) standard motorcycle made by Kawasaki from 1976 till 1983. They rebooted the model in 2017 and have come out with a new model yearly since then. It had a four-cylinder four-stroke DOHC air-cooled wet sump engine with two valves per cylinder and a five-speed gearbox. Designed as a middleweight sibling to the Kawasaki Z1, it competed in the market against the smaller SOHC Honda CB650. The Z650 was the epitome of the "Universal Japanese Motorcycle", or "UJM".
The Z650's project leader was Ben Inamura, who designed the engine of the 1976 KZ650. In its seven-year history, the Z650 underwent a number of iterations, as follows:
This first Z650 had a single front 275 mm disc brake and a 250 mm rear drum. Although the Z650's engine was based on the 900 cc (55 cu in) there were several differences: the 650 used a plain bearing crankshaft with a HyVo (or "Morse") chain primary drive instead of a gear drive, which necessitated the installation of a third (intermediate) shaft in the transmission to drive the input side of the clutch. Another departure from the Z1 engine design was the use of a shim-under-bucket method of setting valve clearances. (The Z1 engine's shim-over-bucket design caused some mishaps when its camshafts flicked the shims out of position, with consequent damage).
The front brake caliper was resited to the rear of the fork leg and the front master cylinder reservoir shape was changed. A hazard switch was added. Needle roller bearings were fitted to the swingarm instead of the earlier plain bushings. Tuning modifications were made to the carbs to improve low speed operation. The manual operation fuel tap was replaced with an automatic diaphragm unit. A rear disc brake replaced the earlier drum.
This model had a self-adjusting (rather than manually-adjusted) camchain tensioner. For US-only models, an air injection system for emissions reduction was fitted. This model was the first Kawasaki to use all-weather sintered disc pads and drilled brake discs to improve braking in the wet. A derivative version, the KZ650SR had "chopper styling" with a fat 16-inch rear wheel.
CDI ignition (instead of points) was introduced. The front end from the 750E was grafted on meaning a change to the brakes, front wheel and clocks. The kick-starter was removed and a passenger grab rail was fitted. Larger 32mm Mikuni CV carbs were fitted, allowing the redline to be lifted from 9,000 to 9,500 rpm. A new generation of Kawasaki cruisers, the "CSR" was introduced.
Changes included new CV carbs, a clutch upgrade, modified fork internals, new switchgear, tail light, and different rear shocks.
Some minor updates including new pistons with four rings, and changes to the cylinder head and cover. After 1983 the KZ650 is surpassed by the GPZ models.
- Hall, Landon (September–October 2007). "1978-1981 Kawasaki KZ650SR". Motorcycle Classics. Retrieved April 21, 2017.
- "Kawasaki Z650 Road Test". Classic-Motorbike.net. December 1, 2011. Retrieved July 19, 2017.
- Neilson, Cook, ed. (November 1976), "Kawasaki KZ650", Cycle, vol. 27 no. 11, pp. 29–36
- Kawasaki Service Manual Part #99924-1007-03 3rd ed. dtd. September 10, 1981, p. 289