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1977 Triumph Bonneville

ABOVE & BELOW: 1977 Triumph Bonneville T140V was essentially carried over from ’76, as would be the practice from now on. Budget constraints were choking the company and it’s products. This one is in the Polychromatic Blue and Cold White paint scheme.

As the 1977 model year opened, the Meriden Co-op was struggling on a shoestring budget and so had to set priorities. The Triumph T160 Trident had been killed off in 1975, now they dropped the 650cc T120 & TR6 series, focusing all their energies in a single motor motorcycle, the 750cc twin, in T120 Bonneville form and also as the TR7 Tiger. For 1977, there were two bikes in the Bonneville lineup: The standard Triumph T140 Bonneville, and a special, limited-edition factory custom, the Triumph Bonneville T140 Silver Jubilee. The Jubilee was meant to commemorate the Silver (25th) Anniversary of Queen Elizabeth II’s reign as Queen of England. The model year started with Engine #GP75000, with the standard Triumph Bonneville 750 model designation being T140V (the “V” signifying a 5-speed gearbox, which all of them had). The Jubilees simply added a “J” suffix after the “V” (ie: T140VJ).

Very few mechanical changes were made to the 1977. Funds were short and the Meriden Co-op had to make do with what they had, wherever possible. The 1977 Triumph T140 Bonneville was pretty much a straight carry-over from 1976, which was itself a carry-over from 1975, which was a carry-over from 1974. So, the basic Bonneville, other than the US-mandated switch to lefthand-shift, had gone unchanged, unimproved for 4 model years, an eternity in the fast-paced motorcycle biz of the day.

ABOVE: The 1977 Triumph Bonneville itself was a very limited edition, with only about 2400 having been made, total. But Triumph Motorcycles continued to produce its mainstream model, the 1977 Triumph Bonneville T140V. This one is in Signal Red and Cold White, which was the color scheme for a TR6 or TR7.

1977 Triumph Bonneville T140VJ

The standard 1977 Triumph Bonneville T140 then remained relatively unchanged from prior years. The only real changes were made to the Jubilee, and they were purely cosmetic. The outer engine covers (primary, timing & gearbox covers) were chromed. A special Silver over Blue with Red pinstriping paint scheme was specific to the 1977 Silver Jubilee. The seat was even blue vinyl with red piping, the colors of the British Union Jack (their flag), along with the silver to tie into the 25th anniversary event.

The Jubilee got special ‘upside-down’ Girling rear shocks with exposed springs, and lots more chrome than the standard Bonnie. The seat was a stepped affair that, apart from the loud colors, would set the pattern for every Bonneville seat from them on. Despite the wild paintjobs, US bikes continued to get US-spec slimline tanks, and UK bikes got the larger-capacity, boxy British-spec tanks. New side covers were added with special Silver Jubilee emblems on them, with the year “1977” and the red, white & blue Union Jack. The original plan was to produce 1,000 of them for the home market to honor the Queen, but they sold so easily that Meriden quickly put together another 1,000-unit run for the US market, then another 400 (+/-) run for general export. The first batch had side cover emblems which read “One of a Thousand”. But once they exceeded that, all subsequent bikes were wisely labeled “Limited Edition”.

ABOVE: Part of the Jubilee package was chromed outer engine covers. They were handsome indeed, but had quality problems due to the low-grade aluminum that the covers were cast from.

In the final analysis, if the 1977 Triumph Bonneville Silver Jubilee had any significance or relevance at all, it wasn’t because of the volume of its sales. While 2,400 extra sales was better than a poke in the eye with a sharp stick, it wasn’t enough to change the fortunes of Triumph Motorcycles. And it wasn’t because it was faster or technologically superior, after all, it was just an appearance package. And it wasn’t because it was such a gorgeous bike. Because it wasn’t. Many people were put off by the looks, in fact, finding it too flamboyant or garish.

No, the Silver Jubilee was significant because it was the first in a series of special, limited edition factory customs that Triumph would produce over the next few years. Again, it wasn’t enough to save the company, but perhaps it prolonged the inevitable just a little while longer, and the strategy brought us some very cool Classic British Motorcycles.

1977 Triumph Bonneville SPECIFICATIONS

T140V Bonneville

T140VJ Bonneville

Engine type


Bore & Stroke




Engine output

Primary drive

Primary sprockets



Ratios, overall:

1st, bottom




5th, top

Final drive

Final drive sprockets

Frame type

Suspension, front

Suspension, rear

Brake, front

Brake, rear

Tire, front

Tire, rear

Fuel capacity


Seat height

Ground clearance


5-speed 750 Roadster

5-speed Silver Jubilee Edition

Air-cooled OHV vertical twin

744cc / 45.0 ci

76mm X 82mm / 2.99″ X 3.23″


2- Amal Concentrics R930/9, 30mm

Battery & coil, Lucas

49 bhp @ 6200 rpm

3/8″ triplex X 84 links

Engine 29T X Clutch 58T

Multi-plate, wet

5-speed constant-mesh, left-foot shift






5/5″ X .400″ X 3/8″ chain X 106 links

Gearbox 19T X Rear 47T

All-welded, oil-bearing large-tube backbone

Telescopic fork, hydraulic damping 2-way

Swing arm, 2 Girling dampers

10″ disk, 2-piston hydraulic caliper

10″ disk, 2-piston hydraulic caliper

3.25″ X 19″ Dunlop, ribbed

4.00″ X 18″ Dunlop, universal

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

54.5″ / 140.3 cm

32.5″ / 77.5 cm

5″ / 12.7 cm

387 lbs/ 176 kg