The 1975 Yamaha RD350 from Japan was powered by a 347cc 2-stroke twin producing 39hp at 7500rpm. Weighing 150.0kg (331 lbs) and with a seat height of 790mm, it was aimed at standard riders.
The 1978 Yamaha XS650 Special by contrast offered 654cc of OHV twin power, delivering 50hp at 7000rpm. Tipping the scales at 205.0kg (452 lbs) with a top speed of 165km/h (103 mph), it offered a distinct riding experience. 1970s bikes from the Japanese superbike revolution are increasingly sought after. Clean, original examples have seen significant value appreciation.
Specifications Comparison
| 1975 Yamaha RD350 | 1978 Yamaha XS650 Special | |
|---|---|---|
| Displacement | 347 cc | 654 cc |
| Power | 39 hp | 50 hp |
| Torque | 33.0 Nm | 50.0 Nm |
| Cylinders | 2 | 2 |
| Top Speed | 165 km/h | 165 km/h |
| Quarter Mile | — | — |
| Dry Weight | 150.0 kg | 205.0 kg |
| Wet Weight | 163.0 kg | 220.0 kg |
| Seat Height | 790 mm | 760 mm |
| Wheelbase | 1345 mm | 1450 mm |
| Fuel Capacity | 13.0 L | 14.0 L |
| Gears | 6 -speed | 5 -speed |
The Verdict
Comparing these two Yamaha machines reveals the brand's evolution. The 1975 Yamaha RD350 laid the groundwork with 39hp, while the later 1978 Yamaha XS650 Special pushed output to 50hp. From a collector's perspective, the 1975 Yamaha RD350 holds the edge with a 7/10 rating. Either way, both are worthy additions to any Yamaha collection. Parts availability is moderate for the 1975 Yamaha RD350 and good for the 1978 Yamaha XS650 Special — an important factor for any restoration project.
About the 1975 Yamaha RD350
Yamaha released the 1975 Yamaha RD350 in 1975 with a 347cc 2-stroke twin powerplant making 39hp — a definitive standard motorcycle.
Full 1975 Yamaha RD350 Profile →About the 1978 Yamaha XS650 Special
The 1978 1978 Yamaha XS650 Special is a 654cc twin-cylinder cruiser that became one of Yamaha's most memorable motorcycles of the 1970s.
Full 1978 Yamaha XS650 Special Profile →