BMW K75C

BMW K75C
Manufacturer	BMW
Also called	K 75 C
Production	1985 - 1995
Class	Naked
Engine	liquid-cooled, four-stroke, longitudinal three cylinder, DOHC, 2 valves per cylinder
Bore / Stroke	66.0mm x 66.0mm
Compression ratio	11.0:1
Top Speed	124 mph (200 km/h)
Horsepower	74.96 HP (55.9 KW) @ 8500RPM
Torque	50.16 ft/lbs (68.0 Nm) @ 6750RPM
Spark Plug	NGK D8EA '86-88
Battery	YUASA 51814 '86-88
Transmission	Gear box: 5-speed, manual Final Drive: shaft Clutch: dry, single plate
Final Drive	Shaft
Suspension	Front: telescopic fork with hydraulic shock absorber Rear: Monolever swinging arm
Brakes	Front: dual 285mm discs, 2-piston calipers Rear: single 285mm disc
Front Tire	100/90-18 56H
Rear Tire	120/90-18 56H
Wheelbase	59.69 inches (1516 mm)
Length	87.4 inches (2220 mm)
Width	35.39 inches (899 mm)
Seat Height	31.89 inches (810 mm)
Weight	236.0 kg (wet)
Oil Filter	K&N KN-163
Fuel Capacity	5.55 Gallon (21.00 Liters)
Related	BMW K75 BMW K75C
Manuals	Service Manual

The BMW K75 was a was a liquid-cooled, four-stroke, longitudinal three cylinder, DOHC, 2 valves per cylinder standard motorcycle produced by BMW from 1985 to 1995. At the time of its introduction, the K75 was BMW's cheapest motorcycle. It offers a claimed acceleration of 0–60 mph in 4.6 seconds and a top speed of 120 mph (193 km/h). Max torque was 50.16 ft/lbs (68.0 Nm) @ 6750 RPM. Claimed horsepower was 74.96 HP (55.9 KW) @ 8500 RPM.

Engine

The engine was a liquid cooled liquid-cooled, four-stroke, longitudinal three cylinder, DOHC, 2 valves per cylinder. A 66.0mm bore x 66.0mm stroke result in a displacement of just 740.0 cubic centimeters. Fuel was supplied via a double overhead cams/twin cam (dohc).

Drive

The bike has a 5-speed, manual transmission. Power was moderated via the dry, single plate.

Chassis

It came with a 100/90-18 56H front tire and a 120/90-18 56H rear tire. Stopping was achieved via dual 285mm discs, 2-piston calipers in the front and a single 285mm disc in the rear. The front suspension was a telescopic fork with hydraulic shock absorber while the rear was equipped with a Monolever swinging arm. The K 75 C was fitted with a 5.55 Gallon (21.00 Liters) fuel tank. The wheelbase was 59.69 inches (1516 mm) long.

Model designations

Black BMW K75S with topbox and panniers, parked on grass

Various models of the K75 were produced.

• K75, with no fairing
• K75T, US only model with a windscreen, touring bags, engine crash bars, and rear top case
• K75C, with a small handlebar mounted 'cockpit' fairing
• K75S, with sports fixed fairing and lower bars
• K75RT, with full fairing for 'road touring'

S and RT versions have a rear disc brake and 17 inch rear wheels whereas the others have a single leading shoe drum brake and 18 inch rear wheels. A stiffer, "anti-dive" front suspension was added to the S and RT model. Later RT version has a windshield that can be raised or lowered. Some taller riders complain of wind buffeting with the smaller S model stock windscreen.

Engine and transmission

All K75 models share the same drivetrain. They are powered by a 740 cc liquid-cooled inline three-cylinder engine with Bosch fuel injection. The US EPA specific engine produce 68 hp while all others produce 75 hp. It utilizes a five-speed transmission with a dry clutch and a shaft-driven final drive. The engine is rotated 90 degrees – designed to be less vulnerable to damage should the cycle fall over.

Background to K75 launch and design

Black BMW K75T with topbox and panniers, parked on a driveway in front of a house and metal gates

The K-series lineup, including the K75 and K100, were not just new models; these designs were radical departures from almost every aspect of previous ones. The K-bikes introduced new technology and refinement for a premium brand. At the time, BMW and Harley-Davidson were the only major manufactures that did not offer liquid-cooled engines. Competing brands, notably of Japanese manufacture, were touting the superiority of their liquid-cooled engines and had introduced low maintenance shaft-drive technology into a growing number of their models.

The K-series offered refinements like computer-controlled fuel injection, all stainless steel exhaust, rust-free aluminum fuel tank, anti-lock brakes or ABS, mono-lever in the rear and single shock absorber, adjustable headlight, high capacity 460 watt alternator, cigarette lighter accessory plug-in, self canceling signal lights. It would take more than two decades for other manufacturers to catch-up. The engine design had excellent vibration isolation. Two different forks manufactures were used: Showa with an outer upper tube diameter of 1.612" and Fichtel and Sachs measuring 1.627".

1985 BMW K 75 C

The 1985 MY BMW K 75C is a middle-class naked machine that comes standard with features such as a suspension package composed of a telescopic fork with a hydraulic shock absorber and a Monolever unit in the rear, cast-aluminum wheels, a nose-fairing with a windscreen, a dual seat, passenger grab rails, a rear luggage rack, mid-mounted foot controls and an analogue instrument cluster.

In the tech/engine department, it sports a liquid-cooled, four-stroke, 740cc, in-line three cylinder powerplant mated to a five-speed manual transmission that can reach a maximum power output of 75 horsepower and 68 Nm of torque.

1986 BMW K 75 C

The 1986 MY BMW K 75C can reach a maximum power output of 75 horsepower and 68 Nm of torque from its liquid-cooled, four-stroke, 740cc, in-line three cylinder powerplant mated to a five-speed manual transmission. It also boasts features such as a telescopic fork with a hydraulic shock absorber and a Monolever unit in the rear, cast-aluminum wheels, a nose-fairing with a windscreen, a dual seat, passenger grab rails, a rear luggage rack, mid-mounted foot controls and an analogue instrument cluster.

1987 BMW K 75 C

The 1987 MY BMW K 75C comes with a telescopic fork with a hydraulic shock absorber and a Monolever unit in the rear, cast-aluminum wheels, a nose-fairing with a windscreen, a dual seat, passenger grab rails, a rear luggage rack, mid-mounted foot controls and an analogue instrument cluster.

In the tech/engine department, it sports a four-stroke, liquid-cooled, 740cc, longitudinal three cylinder powerhouse paired to a five-speed manual transmission, and can reach a maximum power output of 75 horsepower and 68 Nm of torque.

1988 BMW K 75 C

The 1988 MY BMW K 75C sports a four-stroke, liquid-cooled, 740cc, longitudinal three cylinder powerplant mated to a five-speed manual transmission, and can produce a claimed 75 horsepower and 68 Nm of torque. Also, it boasts a hydraulic shock absorber and a Monolever unit in the rear, cast-aluminum wheels, a nose-fairing with a windscreen, a dual seat, passenger grab rails, a rear luggage rack, mid-mounted foot controls and an analogue instrument cluster.

1989 BMW K 75 C

The 1989 MY BMW K 75C is a naked, middle-class two-wheeler that is sure to fit the taste for a wide category of riders. At its heart lies a liquid-cooled, four-stroke, 740cc, longitudinal three cylinder powerhouse paired to a five-speed manual transmission, that produces a claimed 75 horsepower and 68 Nm of torque.

The key features for this machine would be the telescopic front fork with a hydraulic shock absorber, a Monolever suspension in the rear, cast-aluminum wheels, a nose-fairing with a windscreen, a dual seat, passenger grab rails, a rear luggage rack, mid-mounted foot controls and an analogue instrument cluster.

1990 BMW K 75 C

The 1990 MY BMW K 75C boasts a telescopic front fork with a hydraulic shock absorber, a Monolever suspension in the rear, cast-aluminum wheels, a nose-fairing with a windscreen, a dual seat, passenger grab rails, a rear luggage rack, mid-mounted foot controls and an analogue instrument cluster.

In the tech/engine department, this naked sports a liquid-cooled, four-stroke, 740cc, in-line three cylinder powerplant mated to a five-speed manual transmission, and can reach a maximum power output of 75 horsepower and 68 Nm of torque.

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