Triumph Bonneville 650 T120R


Make Model

Triumph T120R Bonneville 650




Four stroke, parallel twin, OHV


649 cc / 39.6 cu in
Bore x Stroke 71 x 82 mm
Compression Ratio 8.5:1
Cooling System Air cooled


2 x Amal 1 - 1/6" carburetors


Lucas MA6 alternator with 2 coils



Max Power

34 kW / 46 hp @ 6500 rpm


Wet, multiplate


4 Speed, constant mesh

Final Drive

Chain, 106 links

Gear Ratios

1st 11.80 / 2nd 8.17 / 3rd 6.76 / 4th 5.84:1
Frame Single front downtube, second bracing member running under tank
Steering Angle 65o

Front Suspension

Telescopic forks, hydraulic damping

Rear Suspension

Swingarm, twin Girling dampers

Front Brakes

8" SLS drum

Rear Brakes

7" SLS drum

Front Tyre

3.25 x 19, Dunlop Universal

Rear Tyre

4.00 x 18, Dunlop Universal


Length 2020 mm / 85.5 in

Width    720 mm / 28.5 in


1403 mm / 55.2 in

Seat Height

775 mm / 30.5 in

Ground Clearance

127 mm / 5.0 in

Dry Weight

165 kg / 363 lbs

Fuel Capacity

13.6 Litres / 3.6 US gal  other Export: 18 Litres / 4.8 US gal
  Cycle 1989

In 1937 Triumph announced a new bike that took the world by storm. Designed by the famed Edward Turner, the 500cc vertical-twinTriumph Speed Twin was so successful that it set a fashion that was quickly followed by all the other major British manufacturers.

Grand Prix Victory
In 1940 during World War 11, the Triumph factory in Coventry was blitzed. Production shifted to a new factory at Meriden, the geographical center of England, where military engines with silicon-aluminum cylinder and head based on the Speed Twin were built Postwar, a Tiger 100 vertical twin with this design won the 1946 Manx Grand Prix. By 1949, British bikes were becoming popular in the United States, and a special American-market Triumph twin, the 650cc Thunderbird, went into production. Triumph became part of the BSA group in 1951.

World Speed Record Breaker
The Triumph twin enjoyed remarkable sport in success and set world speed records on the Bonneville Salt Flats in Utah. In 1955, Triumph power set a speed record of 193 mph and in 1962 raised the record to almost 225-mph. Though the record-breaker was a cigar-shaped projectile on two wheels, from then on Triumph named all of its twin-carburetor sports bikes "Bonneville" to commemorate the event. The BSA group collapsed in 1973 and Triumph merged with Norton-Villiers.

Source bikerenews.com