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Yamaha XS 1100 Sport

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Model

Yamaha XS 1100 Sport

Year

1981

Engine

Four stroke transverse four cylinder, DOHC, 2 valves per cylinder.

Capacity

1101 cc / 67.2 cu-in
Bore x Stroke 71.5 x 68.6 mm
Cooling System Air cooled
Compression Ratio 9.2:1

Induction

4x Mikuni BS 34SS  Carburettor
Lubrication Wet sump

Ignition

TCI additional vacuum adjusted!   /  electric kick starter - Witch is separated from the  engine, for emergency mounting only
Spark Plug BP6ES (NGK) or N-8Y (Champion)
Battery GM 18Z-3A / 12v, 20 AH
Generator A.C. Generator, voltage regulator, rectifier
Starting Electric

Max Power

95 hp / 70.8 kW @ 8500 rpm

Max Torque

9.2 kgf-m / 66.5 lb-ft @ 6500 rpm
Clutch Wet, multi-disc (8 drive plates, 7 driven plates)

Transmission

5 Speed 
Primary Reduction System HY-VO chain & gear
Primary Reduction Ratio 25/25 x 58/35 = 1.657
Final Drive Shaft
Gear Ratio 1st 38/17 (2.235) 2nd 39/24 (1.625) 3rd 36/28 (1.286) 4th 32/31 (1.032) 5th 30/34 (0.882)

Front Suspension

Telescopic fork.
Front Wheel Travel 175 mm / 6.8 in

Rear Suspension

Dual shocks Swing arm, preload adjustable
Rear Wheel Travel 80 mm / 3.1 in

Front Brakes

2x 298mm discs

Rear Brakes

Single 298mm disc

Front Tyre

3.50-19

Rear Tyre

4.50-17
Rake 29º 30
Trail 130 mm / 5.1 in
Seat Height 800 mm / 31.5 in 

Wet Weight

258kg  / 568.7 lbs

Fuel Capacity 

22 Litres / 5.8 gal

After the XS1100, the XS1100. (In some circles it is known as 'Sport'; however you call it there is no difficulty in distinguishing it from the early model, for it has an all-black finish and a small fairing, or big cowling, around the headlamp.)

Brought into Europe for the 1981 season, this big Yamaha was fundamentally unchanged from the original. The engine still put out 95bhp but handling, claimed the makers, had been improved with new rear-suspension units with four-way damping control, and a leading-axle front fork using air pressure up to 15psi. New too on this latest 'Excess' were what Yamaha called italic-spoke wheels, in which the spokes are curved to promote a 'look fast when standing still' look.

After the XS1100 — the XS1100 Sport, dis finish, headlamp cowling and air-assisted, 1981
Testers complained that the fairing caused turbulence, resulting in a disturbed ride at over 100mph. It is difficult, of course, to make a 6001b two-wheeler nimble as well as fast; but other makers, with late designs, got further along this path than Yamaha with this basically mid-1970s big four.