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Yamaha YDS-6

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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