The Suzuki RG500 Gamma is a two-stroke sports motorcycle built from 1985 to 1989. It was directly based on Suzuki’s RG Gamma 500 Grand Prix machine, the bike that took the 500 cc world title with Marco Lucchinelli in 1981 and Franco Uncini in 1982.
Suzuki RG500 at a glance
| Production | 1985–1989 |
|---|---|
| Type | two-stroke sports motorcycle |
| Engine | 498 cc square four, rotary-valve induction, twin crankshafts |
| Cooling | liquid, with thermostatically controlled radiator |
| Frame | aluminium box-section, cast headstock and swingarm |
| Front suspension | preload adjustment and Posi Damp anti-dive |
| Rear suspension | full-floater with a double-sided swingarm |
| GP titles | Lucchinelli 1981, Uncini 1982 |
| Smaller version | RG400, 397 cc, 59 bhp |
History of the Suzuki RG500
From the grand prix bike
The RG Gamma 500 was a road bike built to resemble the factory racer of 1984, with almost identical features to the machine Franco Uncini used with the Gallina team. The racing RG Gamma 500 had won two consecutive 500 cc riders’ championships, with Marco Lucchinelli in 1981 and Uncini in 1982, and the road version carried the same engine layout: 498 cc, naturally aspirated, rotary-valve induction, twin crankshafts and four cylinders arranged as a square four, with thermostatically controlled liquid cooling from a front-mounted radiator.
Chassis
Suzuki used an aluminium box-section frame with castings for the headstock and rear swingarm. The forks had preload adjustment and an anti-dive system called Posi Damp, a common feature on early 1980s sports bikes to control the nose diving under braking. At the rear the full-floater suspension used a conventional double-sided swingarm.
The RG400
A 397 cc derivative, the RG400, was built alongside the 500 and looked identical. It shared the frame, suspension and gearbox but had a narrower bore of 50 mm instead of 56, 59 bhp instead of the 500’s output, different big-end bearings, clutch plates, non-floating front discs and silencers, and its own stickers. Its capacity and power suited the restricted Japanese motorcycle licence of the time, and it was sold in Asian markets.
Design and features
- Square-four two-stroke: 498 cc with rotary valves and twin crankshafts.
- Race-derived chassis: aluminium box-section frame with cast headstock and swingarm.
- Posi Damp: an early anti-dive front suspension system.
- RG400 for Japan: a 397 cc licence-friendly version.
Suzuki RG500 versions
- RG500 Gamma (1985–1989): the 498 cc road model.
- RG400 Gamma: 397 cc and 59 bhp for Asian markets.
The RG500 line grew out of the GT250 and RGV500 racing tradition, and its square-four engine is unique among Suzuki road bikes. More Suzukis are in the Suzuki collection.
Video: Suzuki Rg 500 sound
Video by Sgassone69 on YouTube.
Sources
- Suzuki RG500, English Wikipedia: engine, chassis, RG400, racing titles
