The RZ350 Yamaha Sport Plaza (YSP) for JAPAN

It might have produced less than 50bhp . and had a top speed of not much more 'W^ than 100 mph (I6lkm/h). but for many riders Yamaha's brilliantly raw. racy RD350LC was the high-performance bike of the 1980s - or any other decade, come to that. Certainly, few machines can have brought so much fast and furious enjoyment to so many people, so cheaply, as the liquid-cooled two-stroke twin that Yamaha unleashed in 1981.

The LC's pedigree was impeccable, as it was a descendant of the string of outstanding air-cooled strokers with which Yamaha had established an unmatched reputation for middleweight performance. Models such as the YR5. RD350 and RD400 had kept the tuning-fork logo to the fore through the 1970s, while on the racetrack Yamaha's all-conquering air-cooled twins had been superseded by the liquid-cooled TZ250 and 350. with equally spectacular results.

For all the Race Developed nature of this latest in the RD series, the LC's 347cc engine owed more to that of the RD400 roadster than to the TZ350 racer. The water jacket maintained a constant temperature and allowed the engine to be in a higher state of tunc without loss of reliability. Liquid cooling also helped make the 47bhp motor cleaner and quieter than its air-cooled predecessor; important for environmental reasons although not enough to satisfy US emissions regulations.

The LC's other race-developed feature was its cantilever rear suspension system, which featured a single shock unit mounted diagonally under the seat, instead of the RD400"s twin shocks. Chassis layout was otherwise conventional, with a twin-downtube steel frame, non-adjustable front forks, slightly raised handlebars, attractively rounded styling and a twin-disc front brake.

One ride was enough to get most speed-happy motorcyclists addicted to the Yamaha's exuberant performance. Below 6000rpm it was ordinary; starting easily (with a kick), idling reliably and feeling docile. Then the motor came to life with a scream through its twin pipes, and a burst of acceleration that was as thrilling as it was sudden. With its rider's chin on the tank the LC was good for 110ph (177km/h), but it was the fierce way it got there that made this bike so special.

The Yamaha really handled, too. Its forks were slightly soft, particularly when the powerful front brake was used hard, and the front end could feel decidedly twitchy when the bike was accelerating out of a bend. But the frame was strong, the rear suspension worked well and the LC could be flicked around with the ease and precision of a race-bred machine weighing just 3311b (150kg) with fuel.

All in all the RD350LC was a magical motorbike: fast, reliable (at least when standard), agile, reasonably practical, tuneable, raceable, and most of all brilliant fun. Over the years it was updated several times, notably in 1983 to produce the RD350 YPVS, whose exhaust power valve added mid-range power; and three years later with a full fairing to create the RD350F2. All shared the same key assets: irresistible performance and unbeatable value for money.