BMW R100RS Motorsport Special Edition (1978)

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The BMW R 100RS Motorsport Special Edition motorcycle is a four stroke, two cylinder horizontally opposed Boxer engine bike with a capacity of 980 cc. It has a compression ratio of 9.5:1 and is air-cooled with a wet sump lubrication system. The bike has 2 constant depression carburetors that use battery ignition and a Bosch 12V/240 W alternator, with an electric start. The engine can produce up to 51 kW / 70 hp of power at 7000 rpm and 76 Nm / 7.75 kgf-m / 56 ft-lb of torque at 6000 rpm. The clutch is a dry single plate with a diaphragm spring, and the transmission is a 5-speed with a gear ratio of 1st 4.40 / 2nd 2.86 / 3rd 2.07 / 4th 1.67 / 5th 1.50:1. The bike has a sport version gear ratio of 1st 3.38 / 2nd 2.43 / 3rd 1.93 / 4th 1.67 / 5th 1.50. The rear wheel ratio is 1:2.91 or 1:3.00, with a bevel/crown wheel of 11/32 teeth or 10/32 teeth, and a final drive shaft. The bike’s frame is double-sown tubs, dual cradle, and the front suspension is telescopic fork with hydraulic shock absorber, while the rear suspension is a long swinging arm with an adjustable strut. The brakes consist of two 260mm discs with 2 piston calipers on the front and a Simplex 200mm drum on the rear. The bike has a wet weight of 230 kg / 506 lbs and a fuel capacity of 24 litres / 6.3 US gal, with an average fuel consumption of 4.8 L/100 km / 20.8 km/l / 49 US mpg. The standing 1/4 mile takes 13.9 sec / 157 km/h / 97.3 mph, and the top speed is 196 km/h / 121.5 mph.

Technical specifications:

Make Model: BMW R 100RS Motorsport Special Edition

Year: 1978


Engine: Four stroke, two cylinder horizontally opposed Boxer, 2 valves per cylinder
Capacity: 980 cc / 59.8 cub in.
Bore x Stroke: 94 x 70.6 mm
Cooling System: Air cooled
Compression Ratio: 9.5:1
Lubrication: Wet sump
Induction: 2 x Constant depression carburettors, Bing 94/40/105 – 94/40/106
Ignition: Battery ignition
Alternator: Bosch 12V/240 W
Starting: Electric
Max Power: 51 kW / 70 hp / @ 7000 rpm
Max Torque: 76 Nm / 7.75 kgf-m / 56 ft-lb @ 6000 rpm
Clutch: Dry single plate, with diaphragm spring
Transmission: 5 Speed
Gear Ratio: 1st 4.40 / 2nd 2.86 / 3rd 2.07 / 4th 1.67 / 5th 1.50:1

Gear Ratio Sport Version: 1st 3.38 / 2nd 2.43 / 3rd 1.93 / 4th 1.67 / 5th 1.50
Rear Wheel Ratio: 1:2.91 or 1:3.00
Bevel / Crown wheel: 11/32 teeth or 10/32 teeth
Final Drive: Shaft
Frame: Double sown tubs, dual cradle
Front Suspension: Telescopic fork with hydraulic shock absorber.
Front Wheel Travel: 200 mm / 7.8 in
Rear Suspension: Long swinging arm with adjustable strut.
Rear Wheel Travel: 125 mm / 4.9 in
Front Brakes: 2 x 260mm discs, 2 piston calipers
Rear Brakes: Simplex 200 mm drum
Front Wheel: 2.15 – B19
Rear Wheel: 2.50 – B18
Front Tyre: 3.25 – H19
Rear Tyre: 4.00 – H18
Dimensions: Length 2130 mm / 83.8 in Width 746 mm / 29.37 in Height 1300 mm / 51.8 in
Wheelbase: 1465 mm / 57.67 in
Seat Height: 820 mm / 32.3 in
Ground Clearance: 165 mm / 6.49 in
Wet Weight: 230 kg / 506 lbs

Fuel Capacity: 24 Litres / 6.3 US gal
Consumption Average: 4.8 L/100 km / 20.8 km/l / 49 US mpg
Standing 1/4 Mile: 13.9 sec / 157 km/h / 97.3 mph
Top Speed: 196 km/h / 121.5 mph

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