As the 1970s came to an end, BMW faced three problems from developing its flat-twin boxer engine further: In combination, this meant that BMW's marketing to users of a superior bike, allowing them to price at a premium, was being quickly lost, resulting in a loss of sales and market share.

At the time, BMW, Moto Guzzi, and Harley-Davidson were the only major "high end" manufacturers 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 in a growing number of their models.

While a flat-four engine would have been suited to their boxer tradition and experience, it would also give the appearance that they were copying Honda's GL1000 Gold Wing.

Fritzenwenger's concept was developed by a team led by Stefan Pachernegg[3] based on criteria set out by R. P. Michel and K. V. Gevert.

[2] As an automobile manufacturer, BMW had about twenty years of experience with liquid-cooled overhead camshaft inline engines.

This was carried over to the K100 engine, which used a Bosch LE-Jetronic fuel injection similar to that being introduced on their second generation 3 Series cars.

[16] The K-series has additional refinements including aluminium fuel tanks,[14] adjustable headlights, high capacity 460 watt alternators, Hella accessory plug-in, and self-cancelling turn signal lights.

The K100 was a relative sales success, stemming the losses to the Japanese and changing the media and public perception of BMW.

The four-cylinder engine suffered from secondary vibration, but the three-cylinder K75, with its balance shaft, was far smoother.