1967 Triumph Bonneville


MODEL LINE-UP
The 1967 Triumph Bonneville T120 650 continued to be developed and refined in incremental steps, sometimes one forward and two back. Model designations carried over from late-1966, that is, the TT Special now had it’s own stand-alone model designation, the T120TT. This went along with the traditional T120R Road version, and the T120C off-road/street scrambler (what might have been called an enduro had it been introduced a few years later).


1967 Triumph Bonneville T120R ROADSTER

ENGINE
Starting with Engine # DU44394, new Hepolite pistons were fitted, then starting with Engine #DU47006, stronger connecting rods were installed to deal with the added stress. A hotter exhaust cam (E3134), and in the interest of better oiling for its lobes, things were done, then undone, then redone before settling on a timed oil feed to the tappet block. Chromed steel braces were added between the exhaust pipes and the front of the engine. UK bikes began fitting the smaller US-market mufflers.

GEARBOX
Internal changes were made to the transmission (gearbox) including a new 2nd-gear shift fork & a near-total conversion over from British Standard threads to Unified (American) threads. This process would continue over the next few model years, during which time there was an odd mix of the two thread types, British & American. Two sets of tools were necessary during these transitional years, Whitworth & American.

NEW AMAL CONCENTRICS
The big news for the 1967 Triumph Bonneville was the switch from Amal Monobloc carburetors to Amal Concentrics, starting with Engine #DU59320, now measured in mm instead of inches. They were 30mm & they had a choke for the first time on a Bonneville. Air filters were offered across the line, for the first time.

RUNNING GEAR
The contract breakers received a new auto-advance mechanism & the alternator stator was now encapsulated in resin. An interesting aside: Starting with Engine #DU59230, Triumph stopped using Lucas bulbs & started buying their bulbs from Mazda.

Changes to the frame were minimal. A steering head lock was added & many of the fasters were changed over from British threads to Unified (aka American) threads. UK & Export models swapped their 18″ front wheels for 3.25 X 19″ rolling stock with Dunlop ribbed tires. US bikes kept 18″ wheels on both ends, but the 4.00 X 18″ rear tire option was gaining in popularity among America’s desert racers.


1967 Triumph Bonneville T120 TT SPECIAL

PAINT & TRIM
The seat changed for the first time in years, getting narrower in front to match the new slimline tank & gaining a ‘step’ for the passenger, and was upholstered with lateral ‘tuck-and-roll’ ribs upholstery for the first time. Most US machines sported all-black seats, while most UK & Export models got 2-tone gray & black seats. All had the Triumph logo emblazoned on the back.

ABOVE: The 1967 Triumph Bonneville came in 2 basic color schemes: Aubergine (dark red) & Gold (as above); and Aubergine & Alaskan White (as on the top image). This example has the Aubergine & Gold paint job.

COLOR SCHEMES
Colors for 1967 varied more than ever before. UK and Export machines were Aubergine (a deep red) & Alaskan White, broken up in a new pattern on the tank. US bikes had two options: Aubergine & Alaskan White, just like the UK; or Aubergine & Gold. The US bikes were also painted in a different pattern than ever before, the lower color on the tank (either the Gold or the White) taking on a ‘flying wing/windswept-shape’, for lack of a better way of putting it. Oh and the Smiths magnetic speedometer now went to 150 MPH!


1967 Triumph Bonneville SPECIFICATIONS

Bonneville T120R

Bonneville T120C

Bonneville TT Special

Engine type

Displacement

Bore & Stroke

Compression

Carburetors

Ignition

Engine output

Primary drive

Primary drive sprockets

Clutch

Gearbox

Ratios, overall:

1st, bottom

2nd

3rd

4th, top

Final drive

Final drive sprockets

Frame type

Suspension, front

Suspension, rear

Brake, front

Brake, rear

Tire, front

Tire, rear

Fuel Capacity

Wheelbase

Seat height

Ground clearance

Weight, unladen

Roadster, low pipes

Street Scrambler, high pipes

Competition, TT pipes

Air-cooled OHV vertical twin

649cc / 40.0 ci

71mm X 82mm / 2.79″ X 3.23″

9.0:1 (T120) / 11.0:1 (TT Special)

2- Amal Concentric 30mm / 1-3/16″ (TT)

Battery & coil (T120) / Energy Transfer (TT)

49 bhp @ 6200 (T120) / 52 bhp (TT)

3/8″ triplex chain X 84 links

29T X 58T

Multi-plate, wet

4-speed constant-mesh, right-foot shift

11.8:1

8.17

6.76

5.84

5/8″ X .400″ X 3/8″ chain X 106 links

19T X 47T

Brazed lug, full-cradle, single downtube

Telescopic fork, hydraulic damping

Swing arm, 2 Girling dampers

8″ SLS drum, full width

7″ SLS drum

3.25″ X 19″ Dunlop

4.00″ X 18″ Dunlop

2.5 Imp gal (US) / 4 Imp gal (UK & export)

54.5″ / 140.3cm

32.5″ / 77.5cm

5.0″ / 12.7cm

363 lbs / 165 kg

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