Few such striking bikes have ever come from such an unlikely source as the big, bold and colourful K1 with which BMW stunned the mo

torcycling world in 1989. In recent years the German firm has introduced many innovative and eye-catching machines. But until the K1 appeared, the BMW's name was synonymous with efficient but unexciting tourers.

The K1 had been given its big, aerodynamic coat for two main reasons; firstly as a radical two- wheeled statement, and secondly because BMW had decided to restrict its power output to lOObhp, the voluntary German limit, so the bike needed all the help it could get to boost performance. The big front mudguard, all-covering fairing, swoopy seat and built-in panniers helped the K1 to a top speed of I45mph (233km/h), faster than most bikes managed from lOObhp.

Those 100 horses were produced by a 16-valve version of the liquid-cooled 987cc four-cylinder motor from the K100RS sports-tourer. Unlike Japanese fours, the German firm's K-series engines had cylinders lying horizontally and arranged along the line of the bike. The K1 motor gained lObhp through its more sophisticated fuel-injection system, new exhaust and a few other tuning tricks.

Beneath the bold bodywork, the bmw K1 's chassis was conservative. It was based around a steel space-frame that used the powerplant as a stressed member. Suspension was a combination of Marzocchi front forks and BMW's well-proven arrangement of a single rear shock acting on the swingarm/shaft-drive housing. Brakes were from Brembo; cast wheels carried wide, low-profile radial rubber.


High speed cruising


Despite being BMW's most powerful ever roadster, the KI was in a modest state of tune. Its engine was docile at low speeds, pulling cleanly from tickover right to the 8500rpm redline with no real step in its power delivery. The bike cruised effortlessly at high speed, with a burst of acceleration in hand when required. But acceleration was good rather than exceptional, due partly to the bike's 5701b (259kg) of weight, and the motor vibrated noticeably above 5000rpm.
Handling showed much the same characteristics: it was not racer-sharp but fairly laid-back, requiring a reasonable amount of effort at the handlebars. One advantage of that was that the K1 remained reassuringly stable all the way to its top speed, swallowing high-speed curves without a twitch. The forks were excellent, and although the rear suspension was a little harsh the K1 tracked well over bumps.

It was when there were serious distances to be covered that the K1 came into its own. Its big fairing not only boosted performance but diverted wind from everywhere but the rider's helmet, allowing high cruising speeds. Fuel economy and range were excellent, too, and the broad seat added to the comfort. Annoyingly for such a good long­distance machine, the bike's wind-smoothing rear pockets, barely big enough to carry a toothbrush and credit card, made panniers impossible to fit.

The K1 was a success, for all that. It was a fine sports-tourer. And more importantly, it was a unique and striking machine that began BMW's move from one of the most conservative of bike manufacturers to one of the most bold and imaginative.

No comments:

Post a Comment