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1977 Triumph Bonneville Sliver Jubilee

1977 Triumph Bonneville Silver Jubilee
US-Market Version

ABOVE & BELOW: The US-spec version of the 1977 Triumph Bonneville Silver Jubilee had a typical US-style teardrop tank. (Pictures courtesy of MidAmerica Auctions.)

CELEBRATING A QUEEN

Elizabeth II was crowned Queen of England in 1952. 1977 was the 25th, or Silver Anniversary of her coronation and the entire nation was gearing up for a party. Triumph thought it would be an excellent opportunity to piggyback on the marketing push by producing a special bike commemorating the event. It was to be called the T140LE Bonneville Silver Jubilee Edition, and it was specially decked-out in very regal livery. It started out, as almost all Triumph Specials did, as a stock T140 Bonneville 750. But the Jubilee was given a special Blue-over-Silver paint job with red pin striping and special badging. The stepped ‘king-and-queen’ seat was upholstered in dark blue vinyl with red piping. The color scheme of Red and Blue were meant to pay homage to the British flag, the Union Jack, and the silver of course commemorates the 25th anniversary. All of the external engine covers (primary, timing & gearbox) were chromed, and each bike received a sequentially-numbered Letter of Authenticity. This was purely a cosmetic package, the only real mechanical enhancement was the addition of Girling’s new “Upside-Down Shocks” with exposed springs. This was all meant to honor and also cash in on the Queen’s 25th Silver Jubilee, and Triumph decided to cap production at 1,000 units. But they sold out so quickly that Triumph built another 1,000 just for the US market. When they sold out, they built another 400 for all markets. The first 1,000 bikes had a sticker on the side covers that said “One of a Thousand”. The later bikes say “Limited Edition”. So, this first of the Meriden Co-Ops ‘specials’ was a resounding success. They certainly needed the extra sales, adding up to about 350 bikes per week total, 60% bound for the US market.

ABOVE & BELOW: The 1977 Triumph Bonneville Silver Anniversary had all chromed engine covers, timing, gearbox & primary.

1977 Triumph Bonneville Silver Jubilee
UK-market versions

1977 TRIUMPH SILVER JUBILEE BACKGROUND
By the late 1970s, Triumph, aka the Meridan Co-Op was already struggling, but remained optimistic about their future. This optimism showed itself in several ‘Specials’, or ‘Special Editions’. One of the first was the 1977 Triumph Bonneville Silver Jubilee, technically the T140J. Basically an appearance package for the standard Bonneville, the Jubilee was meant to cash in on, and to honor, the 25th Anniversary of the coronation of Queen Elizabeth II. The UK was enjoying a nationwide celebration and Triumph hoped to garner some much-needed sales. 1,000 units were planned for the British home market, but when the American dealer network got wind of it, they demanded a version of their own, suitably ‘Americanized’. 1,000 additional units were built to accommodate. Even this proved to be insufficient, and another 400 were built. While minuscule volume when compared to Honda, this was stellar success for the cash-strapped Meriden Co-Op. So successful, in fact, that they were encouraged to do other such ‘specials’ over the years. These included the ’79 T140D Bonneville Special, the ’81 T140LE Royal Wedding, the ’83 TSX, and the ’83 TSS.

ABOVE & BELOW: UK-spec bikes used the 4.5-gallon ‘square tank’ that all Brit-market Bonnevilles got, rubber kneepads and all, forcing a less shapely paint scheme. (Picture courtesy of MidAmerica Auctions.)

1977 Triumph Bonneville Silver Jubilee
SPECIFICATIONS

T140VJ Bonneville

Engine type

Displacement

Bore & Stroke

Compression

Carburetors

Ignition

Engine output

Primary drive

Primary sprockets

Clutch

Gearbox

Ratios, overall:

1st, bottom

2nd

3rd

4th

5th, 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

5-speed Silver Jubilee Edition

Air-cooled OHV vertical twin

744cc / 45.0 ci

76mm X 82mm / 2.99″ X 3.23″

8.6:1

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

12.25:1

8.63:1

6.58:1

5.59:1

4.7:1

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