The BMW R 45: a compact, yet potent addition to the BMW family. Its oversquare engine, featuring a fiat-twin configuration with pushrods and rockers, delivers a smooth and efficient ride.
Two stages of tune are available, producing 26bhp for the German market and 35bhp for the rest of the world. The export version boasts a peak power of 7250rpm and maximum torque of 27.51 ft-lbs at 5500rpm.
The R 45’s performance may not be its strongest suit, but it will reach a top speed of approximately 95mph. In contrast, its fuel efficiency is impressive, with an average of 55-60mpg achievable. The bike’s 4.8-gallon fuel tank and five-speed gearbox with shaft drive make it well-suited for touring. Standard features include cast-alloy wheels, audible warnings for the indicators, twin mirrors, electric starter, and a plug for an intercom device. The R 45’s exceptional finish comes at a price, however, with the smallest BMW produced being more expensive than many 750s.
Key Specifications
Engine Type
Four stroke, two cylinder horizontally opposed Boxer, pushrod operated 2 valves per cylinder.
Engine Capacity
453 cc / 27.6 cu in.
Max Power
20 kw / 27 hp
Max Torque
37.5 Nm / 3.82 kgf-m / 27.65 lb-ft @ 5000 rpm
Fuel Tank Capacity
5.8 US gallons / 22.0 L
*n/a – information not provided by manufacturer
All Specifications
Make & Model
Model
BMW R 45
Year
1978 – 79
Engine
Engine Type
Four stroke, two cylinder horizontally opposed Boxer, pushrod operated 2 valves per cylinder.
Displacement
453 cc / 27.6 cu in.
Bore x Stroke
70 x 61.5 mm
Compression Ratio
9.2:1
Max Horsepower
20 kw / 27 hp
Max Torque
37.5 Nm / 3.82 kgf-m / 27.65 lb-ft @ 5000 rpm
Engine Management System
2 x Bing V65 carburetors
Cooling System
Air cooled
Performance
Top Speed
n/a
*n/a – information not provided by manufacturer
Transmission
Gearbox
5 Speed
Final Drive
Shaft
Electrical & Electronics System
Starter
Kick
Chassis & Suspension
Front Suspension
Telescopic hydraulic forks
Front Suspension Travel
175 mm / 6.9″
Rear Suspension
Long swinging arm with adjustable strut
Wheels & Brakes
Front Tire Size
1.85 – B18
Rear Tire Size
2.50 – B18
Front Brakes
2 x 260mm Disc, 2 piston caliper.
Rear Brakes
Single 200mm drum
Dimension & Weights
Fuel Tank Capacity
5.8 US gallons / 22.0 L
Dry Weight
185 kg / 408 lbs
Features
Oversquare engine
26bhp for the German market, 35bhp for the rest of the world
Peak power at 7250rpm, maximum torque at 5500rpm
Fiat-twin configuration engine
Valves operated by pushrods and rockers
5-speed gearbox
Shaft drive
Single cross-drilled disc at the front
Powerful drum at the rear
Cast-alloy wheels
Audible warnings for the indicators
Twin mirrors
Electric starter
Plug for fitting an intercom device
4.8 gallon fuel tank
Excellent fuel consumption, 55-60mpg average
Top speed of approximately 95mph
473cc engine
Hefty 4251b weight
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*We strive to provide the most comprehensive and accurate specifications possible. However, certain details may not be available if the manufacturer did not disclose them or if the information is no longer publicly accessible. If you find any discrepancy with any data on this site, please feel free to let us know at contact@throttlecraze.com
