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.
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 |
