Yamaha XJ650 Midnight Maxim (1981)

The Yamaha XJ650 Midnight Maxim is a motorcycle from 1981, powered by a four-stroke, transverse four-cylinder engine with a capacity of 653cc. It has a 9.2:1 compression ratio, 4x 32mm Hitachi carburetors, and transistorized ignition, producing max power at 71hp/51.8kW @ 9400rpm and max torque at 57Nm/42lb-ft @ 7500rpm. The clutch is wet multiplate, and the transmission is 5-speed with a final drive through a shaft. The bike has a tubular steel dual-cradle frame, 26mm air-assisted telescopic forks, and duel Kayaba shocks with a 5-way adjustable spring preload. The front brake is a single 300mm disc, and the rear brake is a drum. The front tyre is 3.25 H19, and the rear is 130/90 H16. The seat height is 744mm/29.3in, and the dry weight is 203kg/450lbs. The fuel capacity is 13 litres/3.4 US gal, and the consumption average is 47mpg. The standing 1/4 mile time is 12.6 sec/107mph, and the top speed is 120mph.

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Technical specifications:

Make Model: Yamaha XJ 650 Midnight Maxim

Year: 1981

Engine: Four stroke, transverse four cylinder, DOHC, 2 valves per cylinder,

Capacity: 653 cc / 39.8 cu-in

Bore x Stroke: 63 52.4 mm

Cooling System: Air-cooled

Compression Ratio: 9.2:1

Induction: 4x 32mm Hitachi carburetors

Ignition: Transistorized

Starting: Electric

Max Power: 71 hp / 51.8 kW @ 9400 rpm

Max Torque: 57 Nm / 42 lb-ft @ 7500 rpm

Clutch: Wet Multiplate; 7 Steel 8 Friction

Transmission: 5 Speed

Final Drive: Shaft

Gear Ratio: 1st 2.187 (35/16) 2nd 1.500 (30/20) 3rd 1.153 (30/26) 4th 0.933 (28/30) 5th 0.812 (26/32)

Frame: Tubular steel dual cradle frame

Front Suspension: 26mm Air assisted telescopic forks

Front Wheel Travel: 142 mm / 5.5 in

Rear Suspension: Duel Kayaba shocks, 5-way adjustable spring preload

Rear Wheel Travel: 97 mm / 3.8 in

Front Brakes: Single 300mm disc

Rear Brakes: Drum

Front Tyre: 3.25 H19

Rear Tyre: 130/90 H16

Seat Height: 744 mm / 29.3 in

Dry Weight: 203 kg / 450 lbs

Fuel Capacity: 13 Litres / 3.4 US gal

Consumption Average: 47 mpg

Standing 1/4 Mile: 12.6 sec / 107 mph

Top Speed: 120 mph