The Yamaha YM1 is a two-stroke motorcycle that Yamaha produced from 1964 to 1966. With a 305 cc engine and a top speed of about 100 mph, it offered high performance at a modest price for its time.
Yamaha YM1 at a glance
| Maker | Yamaha Motor Company |
|---|---|
| Class | Two-stroke motorcycle |
| Production | 1964–1966 |
| Engine | 305 cc two-stroke |
| Related model | YDS3, 246 cc |
| Lubrication | oil injection into the carburettor intake |
| Top speed | approximately 100 mph |
| Price when new | under $800 |
| Colours | blue/white, red/white and black/white |
Based on one source (English Wikipedia).
History of the Yamaha YM1
The YM1 was produced from 1964 to 1966 with a 305 cc two-stroke engine. It shared many common parts with the 246 cc YDS3 and was virtually identical in all respects apart from bore and stroke, so the two models formed a closely related pair.
Its oil-injection system fed oil to the carburettor intake, increasing the flow as the throttle opened. That gave the engine enough lubrication for the crankshaft, cylinders, connecting rods and pistons without requiring the rider to premix oil and petrol, and it used less oil in the process.
The YM1 was available in blue/white, red/white and black/white colour schemes and had a top speed of approximately 100 mph. It was an economical machine with high performance: priced originally under $800, it could approach 100 mph at a time when such a speed was unusual for a small-capacity motorcycle.
Design and features
- 305 cc two-stroke: a larger version of the YDS3 engine, differing mainly in bore and stroke.
- Oil injection: oil fed to the carburettor intake, with flow rising as the throttle opened.
- High performance: about 100 mph from a small-capacity machine.
- Low price: originally sold for under $800.
Yamaha YM1 versions
- YM1 (1964–1966): the 305 cc model.
- YDS3: related 246 cc model sharing most parts.
The YM1 belongs with other early Yamaha two-strokes such as the DS7. More models are in the Yamaha collection.
Sources
- Yamaha YM1, English Wikipedia: production, engine, oil injection, colours, performance, price
