1959 Triumph Bonneville T120
The 1959 1959 Triumph Bonneville T120 packs a 649cc OHV twin engine with 46hp into a standard motorcycle package from Triumph.
Specifications
Engine
- Type
- OHV twin
- Displacement
- 649 cc
- Cylinders
- 2
- Power
- 46 hp @ 6500 rpm
- Torque
- 52.0 Nm
- Compression
- —
- Bore × Stroke
- 71.0 × 82.0 mm
- Cooling
- Air-cooled
- Fuel System
- 2x Amal carburetors
Chassis & Transmission
- Frame
- Steel single cradle
- Front Suspension
- Telescopic fork
- Rear Suspension
- Twin shock
- Front Brake
- Drum
- Rear Brake
- Drum
- Front Tyre
- —
- Rear Tyre
- —
- Transmission
- 4-speed
- Final Drive
- Chain
Performance
- Top Speed
- 177 km/h (110 mph)
- ¼ Mile
- —
Dimensions & Weight
- Dry Weight
- 172 kg (379 lbs)
- Wet Weight
- 185 kg (408 lbs)
- Seat Height
- 790 mm
- Wheelbase
- 1400 mm
- Ground Clearance
- —
- Fuel Capacity
- 14.0 L
History & Story
Triumph's 1959 Triumph Bonneville T120 arrived in 1959 as a standard motorcycle designed for the discerning rider. Produced in United Kingdom, it quickly earned recognition as a capable standard motorcycle from the 1950s.
At the heart of the 1959 Triumph Bonneville T120 sits a 649cc OHV twin engine producing 46 horsepower at 6500 rpm. The twin-cylinder powerplant features a twin-cylinder layout with air-cooled cooling, fed by 2x Amal carburetors. Power reaches the rear wheel through a 4-speed transmission and chain final drive.
The chassis employs a steel single cradle frame with telescopic fork up front and twin shock at the rear. Stopping power comes from drum front and drum rear brakes. Tipping the scales at 172 kg (379 lbs) dry, the 1959 Triumph Bonneville T120 offers a manageable riding experience with a 1400 mm wheelbase.
Performance-wise, the 1959 Triumph Bonneville T120 achieves a claimed top speed of 177 km/h (110 mph). With a fuel capacity of 14.0 liters, it offers reasonable range for standard motorcycle duties. The seat height of 790 mm makes it comfortable for most riders.
Today, the 1959 Triumph Bonneville T120 is considered a highly sought-after classic that commands strong prices among collectors worldwide. Parts availability is rated as good, making ownership relatively straightforward. It remains an icon of Triumph motorcycling from 1950s.
At the heart of the 1959 Triumph Bonneville T120 sits a 649cc OHV twin engine producing 46 horsepower at 6500 rpm. The twin-cylinder powerplant features a twin-cylinder layout with air-cooled cooling, fed by 2x Amal carburetors. Power reaches the rear wheel through a 4-speed transmission and chain final drive.
The chassis employs a steel single cradle frame with telescopic fork up front and twin shock at the rear. Stopping power comes from drum front and drum rear brakes. Tipping the scales at 172 kg (379 lbs) dry, the 1959 Triumph Bonneville T120 offers a manageable riding experience with a 1400 mm wheelbase.
Performance-wise, the 1959 Triumph Bonneville T120 achieves a claimed top speed of 177 km/h (110 mph). With a fuel capacity of 14.0 liters, it offers reasonable range for standard motorcycle duties. The seat height of 790 mm makes it comfortable for most riders.
Today, the 1959 Triumph Bonneville T120 is considered a highly sought-after classic that commands strong prices among collectors worldwide. Parts availability is rated as good, making ownership relatively straightforward. It remains an icon of Triumph motorcycling from 1950s.
Known Issues
- Oil leaks from primary chaincase
- Lucas electrics (nicknamed Prince of Darkness)
- Sludge trap cleaning essential
- Amal carburettor wear and jetting issues
- Period-correct fasteners and hardware hard to find
Fun Facts
- Pristine examples of the 1959 Triumph Bonneville T120 can command six-figure prices at auction
- The 1959 Triumph Bonneville T120 is considered one of the most collectible motorcycles from Triumph
- The 1959 Triumph Bonneville T120 is widely regarded as a milestone in motorcycle history
Collector Information
- Parts Availability
- Good
- Collector Rating
- 9/10
Resources & Parts
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