Glory of the Gamma: The Suzuki RG500, A Street-Legal 80s MotoGP Replica

Glory of the Gamma: The Suzuki RG500, A Street-Legal 80s MotoGP Replica

MotoGP is, without a doubt, the most prestigious league of motorcycle racing. Whether it is indeed the most thrilling, exciting, dangerous or dramatic form of bike racing is up for debate, of course – there’s the Isle of Man TT, the Dakar Rally, Freestyle Motocross, and a host of other forms of motorcycle racing that one could argue outshine MotoGP in various areas – but there’s no doubt that MotoGP has the most money thrown at it, the biggest sponsorship deals, and the most intense research, development and investment on the part of the various motorcycle marques who compete for the coveted trophy.

In 2015, Honda offered Joe Public a chance to legally own a bike that was, for all intents and purposes, a MotoGP machine with lights and turn signals on it. The RC213V-S was touted by many as being the first truly street-legal MotoGP bike (as long as you purchased the Sports Kit to unleash the bike’s true potential), outdoing contemporary rivals for that title such as Ducati’s Desomsedici RR and Yamaha’s YZF-R1 M, but the fact of the matter is that the first king to sit on this aluminium throne established his brief but thrilling reign way back in 1985. His name was Gamma … the Suzuki RG500 Gamma.

1987 RG500 Front View
1987 RG500 Front View

About the only place you’ll find two-stroke motorcycles still racing competitively these days is in certain types of off-road races, and a few street and track races with machines of a smaller cc; by and large, the vast majority of bike racing is dominated by (and often limited exclusively to) four-stroke machines. This includes MotoGP, of course, but this is a comparatively recent development in its history; from the 1970s to the early 2000s, the premier class of Motorcycle Grand Prix racing consisted of 500cc two-stroke four-cylinder bikes.

Suzuki weren’t the first to produce a road bike heavily-inspired by the MotoGP machinery of the day; prior to the release of the Suzuki RG500 in 1985, Yamaha had already long since wheeled their first RD500s out of the factory into showrooms across the world. In ’85, Honda also produced their own Grand Prix-like offering, the NS400. However, as awesome as both of these bikes were, they were far more street than track, tame enough for the average rider to not kill themselves instantly on, and inspired by rather than replicating the vicious two-stroke race machines their designs aped. As for the RG, though, it was pretty much as close to Suzuki’s factory racer of the day as Honda’s RC213V-S is to Marc Márquez’s track machine.

In totally stock form, the liquid-cooled Suzuki Gamma 500 puts out around 95 horsepower, which doesn’t sound particularly impressive, especially when compared to today’s superbikes, which routinely cross the 200 brake horsepower line, but the 500’s secret sauce was its weight: dry, the Suzuki weighed in at a positively anorexic 154 kgs, which was far lighter than even the ultra-lightweight GSXR750 of the day, and lighter even than Honda’s smaller NS400. Furthermore, by taking a few of the road-legal necessities off the RG Gamma, you could quite easily drop a good 20-odd kilograms off its weight. To get some real brutality out of the already-potent engine, you could swap out the stock pipes, which were somewhat constricted by noise and other legal restrictions, for performance expansion chambers. With mild tuning and modding, the Suzuki Gamma could weigh a mere 135-ish kilos and put out upwards of 110 horsepower.

RG500 Instrument Panel
RG500 Instrument Panel

The Suzuki RG500 engine was rather unique in layout; unlike many other two-stroke race reps of the period (including Suzuki’s own RGV 250, another legendary two-stroke race-rep from the marque), it was a square four. The engine design was not simply developed with the Grand Prix race machine’s motor as a source of inspiration; no, the RG’s engine was almost an exact copy of the factory track machines’, specifically those ridden to podium wins by Barry Sheene in the late ‘70s. Yes, it was a slightly earlier design than that of the contemporary racer, but it was a bang-on dead ringer for a race motor nonetheless. The square four design allowed not only for extreme compactness of the engine, but also meant that the engine could be significantly lighter than Yamaha’s V4 in their RD500 (which was also known as the RZV500, depending on what part of the world you were in), which needed a balance shaft.

Peak power comes on at 9,500 rpm, but the Gamma keeps revving all the way to 12,500 revs, albeit without producing much more, if any more, power in the higher revs. Because it’s a road-going motorcycle and not a one-trick track machine, the RG’s powerband is broader than that of its race machine twin; on the street it’s simply not practical to have a manically furious but ultra-narrow powerband of a mere 2,000 odd revs. Suzuki’s engineers thus attempted to make the RG a little more useable on the street by adding SAEC (Suzuki Automatic Exhaust Control) chambers to the head and cylinders, which allowed for a broader and more useable powerband, although this does skim off a bit of top-end power.

Despite the presence of the SAEC system, there’s no getting around the fact that the RG500 is a highly tuned two-stroke race replica. Barely anything happens below 5,000 rpm, with the stock expansion chambers burbling with such gentle inoffensiveness that you could be fooled into thinking you were riding a scooter. The pain in your wrists from the low-down racer crouch the fork-mounted clip-ons generate, though, would soon dispel any such illusions … as would the kick of power and the unearthly wail from the pipes that comes on when the tacho needle passes 5k. That kick becomes a brutal surge when you pass 7,000 rpm and get into the meat of the two-stroke powerband, and the wail becomes a glorious scream.

RG500 Rear View
RG500 Rear View

All right, so the RG accelerated like a pukka race bike, but did it handle like one? The tyres on this beast are exceptionally skinny by today’s standards, with the Gamma running a 110-section front (16 inch) and 120 on the rear wheel (17 inch). However, at the time, when even the biggest, heaviest monsters were running tyres on the rear that are skinnier than the front tyres of most of today’s superbikes, the RG’s rubber provided more than enough knee-down capability when hurtling through the bends. Contemporary reviewers tended to favour the handling Honda’s NS400 when it came to shootouts between the RD, the NS and the RG, but were usually quick to state that the Gamma’s handling came a very close second. If you ride one back to back with something like a modern R6 or GSXR it’s going to feel like a bit of a barge, of course, but in the context of its time, the RG handled superbly.

Let’s talk looks now – a topic I’m surprised it’s taken me this long to bring up. The Suzuki RG500 is an absolute stunner of a machine, and you can bet that back in ’85 it was turning heads and dropping jaws as dramatically as a nude Bo Derek or Phoebe Cates taking a midday stroll down the local high street would have. While fully faired race replica motorcycles are a dime a dozen nowadays, and have been since the late 80s, in the earlier years of the decade of excess most road-going bikes were of the naked variety, or only sported a bikini fairing. The RG Gamma looked positively space-age in comparison to the naked or semi-naked UJMs with whom it shared the showrooms of the day.

RG500 Rear Wheel
RG500 Rear Wheel

Most RGs were attired in either standard Suzuki blue and white livery, or a white, red and black, but there were some rarer colour combos too. A Skoal Bandit green and white scheme was offered by some dealers, but in my humble opinion, the black and red Walter Wolf colour scheme takes the cake for most bad-ass; there’s just something about black and red paint (and a red seat) along with gold trim that just screams 80s bike nostalgia to me through a screeching megaphone. And speaking of ass, the rear end of the RG is a beautiful sight for any two-stroke fan, with two silencers poking out of the tail section and the other two slightly upswept on either side of the rear wheel. Up front, the narrow RG sports a square headlight and a tall, broad windscreen with a black rubber lip – another uniquely 80s touch.

It’s 2020 now and the days of manic, beastly two-stroke 500s tearing up MotoGP racetracks are long gone, but the dream of those mad years of two-stroke dominated track racing live on in the few remaining pristine RGs that are, quite rightly, prized as collector’s items. The RG500’s production run was as narrow as a two-stroke racer’s powerband, with the final units rolling out of the Suzuki factory in ’87; the success of their revolutionary GSXR750 had put the first nail in the two-stroke coffin, although it would take more than a decade to nail that casket shut completely. Only a few thousand Gammas were ever produced, and RGs thus command a hefty price today. If you can find one at a decent price (or find one for sale at all), consider yourself a lottery winner. Grab it, treasure it, and keep it safe, but not necessarily secret … let those four pipes howl the way they were meant to, once in a while.

A Final Note
Although most of these models are now in the hands of collectors, you can still get hold of a small memento from this era – a scale model. Japanese manufacturers Tamiya make the RG500’s little brother the RG250 in a 1 ½ scale model. It comes in the traditional blue & white colour scheme, and you can get more info on it over on the Amazon listing page.

Suzuki RG500 Image Gallery

Model history

1985 – Suzuki RG500F released to market
1986 – Suzuki RG500G released to international markets, very similar to RG500F model
1987 – Suzuki RG500H released in small numbers. Special “Walter Wolf” edition with red/black/gold color scheme is released in very limited numbers
1987 – RG500 model is discontinued, though old stock is sold for the next couple of years

RG500 Ads, Articles & Brochures

1985 RG500 Brochure.

1985 RG500 Article (UK).

1986 RG500 Article (Canada).

1986 RG500 Article (UK).

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[…] one could come, back in the mid-80s anyway. True, there were the big 500cc two-stroke race reps – Suzuki’s RG500 and Yamaha’s RD500 – but as impressive as they looked, their weight and motors, coming in a […]