The Yamaha YDS-7 is a motorcycle produced in 1972 with a two-stroke, piston-port, parallel twin engine that has a capacity of 247 cc. It has a bore and stroke of 54 x 54 mm, and a compression ratio of 7.5:1. It is air-cooled and is equipped with a 26mm Mikuni induction system and Mitsubishi contact breaker ignition. The motorcycle has a maximum power of 30 hp at 7500 rpm and a maximum torque of 21 ftlb at 7000 rpm. It is equipped with a wet, multi-plate clutch and a 5-speed helical-gear primary drive transmission with a chain final drive. The front suspension features 34mm telescopic forks, while the rear suspension has twin shocks. The brakes are 180mm twin leading shoe drum in the front and 180mm single leading shoe in the rear. The YDS-7 has a wheelbase of 1300 mm and a wet weight of 145 kg with a fuel capacity of 11.4 liters. It has a top speed of approximately 90 mph (145 km/h) and can reach 30 mph in top gear at around 2,500 rpm. The front and rear wheels are equipped with 300 x 18 and 3.25 x 18 tires, respectively. Overall, the Yamaha YDS-7 is a reliable and durable motorcycle that is well-suited for commuting and touring.
Technical specifications:
Make Model: Yamaha YDS-7
| Year | 1972 |
|---|---|
| Engine | Two stroke, piston-port, parallel twin |
| Capacity | 247 cc / 15.0 cu-in |
| Bore x Stroke | 54 x 54 mm |
| Compression Ratio | 7.5;1 |
| Cooling System | Air-cooled |
| Induction | 26mm Mikuni |
| Ignition | Mitsubishi contact breaker |
| Starting | Kick |
| Max Power | 30 hp @7500 rpm |
| Max Torque | 21 ftlb @ 7000 rpm |
| Clutch | Wet, multi-plate clutch mounted on left side of crankshaft |
| Transmission | 5 Speed Helical-gear primary drive. Rear chain % x %in with top guard. Engine rpm at 30 mph in top gear, approximately 2,500. |
| Final Drive | Chain |
| Front Suspension | 34mm Telescopic forks |
| Rear Suspension | Twin shock |
| Front Brakes | 180mm twin leading shoe drum |
| Rear Brakes | 180mm single leading shoe |
| Front Tyre | 300 x 18 |
| Rear Tyre | 3.25 x 18 |
| Wheelbase | 1300 mm / 51.1 in |
| Wet Weight | 145 kg / 320 lbs |
| Fuel Capacity | 11.4 Litres / 3.0 gal |
