Yamaha’s RD350LC: Of a generation

It’s the noise and acceleration above 6000rpm that is still so addictive; the sudden burst of activity every time the throttle is wound back in anger and the 347cc two-stroke motor comes alive.

You might think the thrill would have worn off after all these years, especially now so many bikes produce far more performance than this elderly machine from the early Eighties.

But if the RD350LC can no longer deliver the giant-killing speed on which its mighty reputation is based, the little Yamaha still puts a broad smile on its rider’s face with every ride. So much so that, if you were to make a list of the most popular motorcycles of all time, it should surely feature prominently. In fact when a certain weekly paper recently held a vote to decide just that, the ‘Elsie’ came out on top – ahead of the FireBlade, R1200GS and all the rest.

That’s quite an achievement for a humble Japanese twin that produced less than 50bhp and had a top speed of not much more than a ton, but for many riders Yamaha’s raw, racy LC was the high-performance bike of its day. Certainly, few machines can have brought so much fast and furious enjoyment to so many as the liquid-cooled two-stroke twin that Yamaha unleashed in 1981.

In many ways the LC had the lot: speed, excitement and handling – plus reasonable practicality, reliability and economy. Although it had an appetite for fuel and two-stroke oil, it was relatively cheap to buy and to run. And it looked great too, with a restrained style that contrasted with its outrageous personality. No wonder it was such a success.

The RD350LC was a descendant of the string of outstanding air-cooled two-strokes with which Yamaha had established an unmatched reputation for middleweight performance. The line had begun with the YR1 model in 1967. And throughout the Seventies, models such as the 350cc YR5, RD350 and RD400 had kept the tuning-fork logo to the fore. The ‘RD’ initials stood for race developed and were well earned because most of the Yamaha twin’s gains in performance and reliability were due to the firm’s efforts on the track.

Perhaps surprisingly the initial reaction was not universally positive, with some testers wondering whether the LC was too peaky and aggressive to appeal to more than a limited section of the market. Well, maybe it didn’t appeal to everyone – but for all those riders looking for high performance on a low budget, no other bike even came close. With a 110mph top speed, wheelie-popping acceleration and racetrack credibility, this was the stuff of a speed-crazed teenager’s dreams.

The LC needed little help to become a hit for Yamaha, but it got some assistance anyway in the form of a hugely popular one-make racing series. This began in Britain as the RD350 Pro-Am Series, contested by a mixture of professional and amateur riders (hence the name) including future 500cc works GP racer Niall Mackenzie. They rode identical LCs, prepared by Yamaha and allocated after keys were drawn out of a hat.

The result was outrageously close, aggressive, crash-littered and generally spectacular racing, which became unmissable TV viewing for millions at a time when bike racing was rarely seen on the box. The original Pro-Am challenge soon led to an international series that included riders from many European countries plus Australia. In the last couple of years, some of the original stars have squeezed into their leathers to take part in Pro-Am revival races, contested on restored LCs. Reliability was one of the LC’s many attributes, both on road and track, although it wasn’t infallible. Engine studs sometimes broke,

and exhausts cracked due to engine vibration before the design was changed. Yamaha modified the carbs to prevent misfiring, revised the rich-running oil pump and the beefed-up the exhaust mounts with tie-rods under the engine. They also introduced a new black/red ‘Mars Bar’ colour scheme, along with an optional bikini fairing and belly-pan and, in some markets, a full fairing.

The original LC’s reign was short, because for 1984 it was replaced by an all-new model, characterised by the new exhaust, whose flap moved at certain revs to optimise volume for both high- and low-speed running. The YPVS, or Yamaha

Power Valve System,

gave slightly stronger midrange delivery with no loss of top-end, and led to the bikini-faired Yam, officially the RD350LC YPVS, being known as the Power Valve.

Other mods including a bikini fairing, air-assisted forks, rising-rate shock and tubeless tyres helped make it another hit. That mid-Eighties period of the Power Valve’s rule was probably the high point of the RD350LC’s existence, but the model was not finished yet.

The fully-faired 350LC F2 and naked 350L N models were also fairly popular, partly because switching production to South America helped keep prices low. The fully-faired LC initially had a rectangular headlight, then went to twin round headlights in the early Nineties, remaining in Yamaha’s range until 1994 as the RD350R.

With its performance little changed, the Yam’s reputation had inevitably faded, and most young riders dreamt about the more glamorous and expensive FZR400RR four instead.

By the time the two-stroke was phased out in the mid-Nineties it had lasted in its various forms for well over a decade, it had sold in huge numbers all over the world, and it confirmed its status as the ultimate poor boy’s superbike.