Suzuki have been developing and refining a square four, two-stroke motorcycle for years. Since 1976 they have had at least one new model for every year but none of them was for sale. They were the exclusive property of the paid factory riders and were all works race bikes.

Barry Sheene won the 1976 and 1977 500cc World Championships on an RG500. So did Marco Lucchinelli in 1981 and Franco Uncini in 1982. At the highest level of competition, the blue riband 500cc Grand Prix, Suzuki's RG has always been a fierce and formidable contender.

In 1985, Suzuki unveiled a stunning, spellbinding RG500 Gamma for the road. One might describe it as an authentic racer with lights.

The race replica wars have certainly come a long way: replicas are now arguably as fast as some of the original racers on which they are based. Like the racing Gamma's, the street-legal RG is a liquid-cooled, twin crank, square four with disc valve induction. Fed by four ultra-thin, 28mm flat slide Mikuni carburettors located on the outside of each cylinder, and with the gas helped by Suzuki's intake power chamber on the way in and their power valve on the way out, the Gamma revs way beyond the redline and makes power in huge peaks of blistering stomp.

 There is little below 6,000rpm but it revs hard and fast to 9,000 where it starts falling away but then at 9,500rpm it is suddenly back on the pipe and bang, it revs wildly and is making horsepower up to 12,000rpm. Acceleration is mind-bending. Whacking open the throttle has those four tiny, delicate carburettors dancing at the end of their cables and cracking instantly into life. Run flat out through six well-spaced gears, it is still accelerating at 135mph and 9,500rpm in top.

Despite its peaky rev-craziness, the engine is not animal-like in behaviour and response. It is possible to drop below 6,000rpm without it dying or oiling up the plugs. The power is progressive and fairly smooth for a two-stroke.

At 3401b the Gamma is remarkably light for its size but it is also fairly tall. The alloy double cradle frame and full floater monoshock suspension do a fine job of keeping the wheels on the ground. The steering is not just quick but fast. It needs a positive, deliberate riding style but the reward is razor-sharp handling and beautiful roadholding. In order to reduce speed quickly the bike has very powerful brakes - twin 260mm front discs with four pot calipers that used hard will tear the rubber off the 16in front tyre.