| Yamaha RD250 | |
| Aka: | Yamaha RZ250 |
| Manufacturer: | Yamaha Motor Company |
| Production: | 1973–1987 |
| Predecessor: | Yamaha DS7 |
| Successor: | Yamaha TZR250 |
| Class: | standard |
| Engine: | , two-stroke |
| Bore Stroke: | 54× |
| Compression: | 6.7:1 |
| Related: | Yamaha RD350, Yamaha RD350LC, Yamaha RZ350 |
The Yamaha RD250 is a two-stroke motorcycle produced by Yamaha Motor Corporation between 1973 and 1987.
Four generations of RD (also known as the RZ250 in the Japanese and Australian markets) were produced: the air-cooled models from 1973 up to 1979, and from 1980 until 1987 the liquid cooled models; known as the RD250LC, RD250LC-II and RD250 YPVS. The name RD stood for Race Developed.
The standard bike weighed 152 kg dry and had a 247cc 2-stroke twin engine that produced 30 hp.[1] It had a 5 speed gearbox. There were 6 speeds, 6th was blocked off but very simple to reinstate by removing a blanking plate on the gear selector drum. The motorcycle had chain final drive.
In 1983 the UK government reduced the maximum cc for learners to 125,[2] killing off the 250 cc motorcycle class in a stroke. At the time, it was considered that the reason for the sudden change in the law was the RD250 which put a high-speed vehicle into the hands of inexperienced users.