At the end of the 1970s, BMW Motorrad faced the technological challenges imposed by the new and stringent emissions regulations in the United States. Rather than viewing this challenge as a threat, BMW Motorrad saw it as an opportunity to develop an entirely new range of high-tech motorcycles.
Innovation in Engine Design
Although the traditional BMW Motorrad two-cylinder boxer engine, which is distinctive to the brand, continued to be a hallmark, BMW leveraged its expertise in engineering and manufacturing four-cylinder car engines to create an innovative solution for its motorcycles. The BMW K100 would feature a 987 cubic centimeter inline four-cylinder engine, installed longitudinally in the chassis of a new generation of motorcycles.
This engine was positioned horizontally, with the engine head to the left of the motorcycle and the crankshaft to the right. This configuration allowed the use of a single set of bevel gears to transmit power to the rear wheel, rather than the two sets of gears typically required for vertical engines, resulting in reduced power loss, weight, and complexity. Additionally, this layout helped maintain a low center of gravity, improving dynamic performance.
First BMW Motorcycle with Electronic Injection
The engine of the BMW K100 was the first in BMW Motorrad (and one of the first worldwide) to feature an electronic fuel injection system, similar to that used in the second-generation BMW 3 Series (E30). Thanks to the electronic fuel injection, combined with an electronic ignition system, it was possible to use a catalytic converter, thereby meeting the strictest emission regulations of the time.
Innovation in Braking Systems
BMW Motorrad, always in search of technological solutions to improve safety, developed and installed an anti-lock braking system (ABS) for motorcycles for the first time on the K100. This technology was highly valued by customers, since at that time most serious motorcycle accidents were related to braking maneuvers when cornering. Existing BMW Motorrad customers enjoy new generations of this technology, tailored to specific types of motorcycles and with features such as ABS deactivation for dual-purpose motorcycles on gravel or dirt surfaces.
Commercial Success and Variants
Motorcyclists quickly recognized the numerous advantages of the BMW K100, leading to the development of additional variants such as the K100 C, K100 RS, K100 RT, and K100 LT, which included aerodynamic covers and configurations for longer trips. In addition to private users, BMW also prepared the K100 TIC for police forces, fire departments, medical services, and military applications.
The Three Cylinder Variant: K75
To maximize the potential of this new motorcycle platform, BMW developed a three-cylinder variant called the K75. The BMW K75 featured a balance shaft system that eliminated the inherent vibrations of the three-cylinder engine, resulting in even smoother operation than the K100, which already had an excellent vibration isolation system.
BMW K1 Aerodynamics
The BMW K1 made its debut at the IFMA Motorcycle Show in Cologne, Germany, in 1988, standing out for its futuristic and aerodynamic design, as well as its new 1,000 cc four-cylinder engine with four valves per cylinder, capable of developing 100 horsepower and accelerating from zero to 100 km/h in under four seconds. The BMW K1 arose from BMW Motorrad’s need to present an alternative and sportier proposal, with a powerful liquid-cooled engine that would shift public perception. Despite the success of the boxer engine, the BMW K1 of 1983, led by Josef Fritzenwenger and Stegan Pachnernegg, represented a radical plan.
Starting from the prototype, BMW engineers added a fairing that offered an aerodynamic drag coefficient (Cd) of 0.34, the lowest for motorcycles at the time, and made multiple improvements to maximize performance, launching the production model in the late 80s. Although only 6,921 units of the BMW K1 were produced, it achieved its goal of changing the industry’s perception of BMW Motorrad, demonstrating that the brand could produce modern motorcycles with a high degree of technological innovation. This capability has been confirmed with BMW Motorrad’s current lineup.