Posts in category

Engine Type


1950 VINCENT COMET RUNNING GEAR The Vincent Comet had frame similar in layout to the V-twin Vincent Black Shadow which included Vincent’s proprietary cantilever rear suspension and Vincent’s Girdraulic forks up front. And, like the big V-twins, the engine was a stressed member of the frame, eliminating the need for front downtubes and an engine …

1952 VINCENT BLACK SHADOW BACKGROUND Brilliantly designed by doubling up the 499cc Vincent Comet single-cylinder engine into a 50-degree V-twin, the Vincent Black Shadow was introduced in 1949. It followed on the heals of the Vincent Rapide, which was more of a touring bike. The buying public wanted more power, more “sport” and so the …

1953 VINCENT BLACK SHADOW BACKGROUND Brilliantly designed by doubling up the 499cc Vincent Comet single-cylinder engine into a 50-degree V-twin, the Vincent Black Shadow was introduced in 1949. It followed on the heals of the Vincent Rapide, which was more of a touring bike. The buying public wanted more power, more “sport” and so the …

1936 VINCENT COMET FRAME & CYCLE GEAR The Vincent Comet had frame similar in layout to the V-twin Vincent Black Shadow which included Vincent’s proprietary cantilever rear suspension and Vincent’s Girdraulic forks up front. Also typical of Vincent motorcycles, the Comet had two Single Leading-Shoe (SLS) front drum brakes, one on each side. 1936 VINCENT …

1935 VINCENT COMET RUNNING GEAR The Vincent Comet had frame similar in layout to the V-twin Vincent Black Shadow which included Vincent’s proprietary cantilever rear suspension and Vincent’s Girdraulic forks up front. Also typical of Vincent motorcycles, the Comet had two Single Leading-Shoe (SLS) front drum brakes, one on each side. COMET ENGINE DESIGN The …

1950 VINCENT BLACK SHADOW BACKGROUND Brilliantly designed by doubling up the 499cc Vincent Comet single-cylinder engine into a 50-degree V-twin, the Vincent Black Shadow was introduced in 1949. It followed on the heals of the Vincent Rapide, which was more of a touring bike. The buying public wanted more power, more “sport” and so the …

1949 VINCENT COMET RUNNING GEAR The Vincent Comet had frame similar in layout to the V-twin Vincent Black Shadow which included Vincent’s proprietary cantilever rear suspension and Vincent’s Girdraulic forks up front. And, like the big V-twins, the engine was a stressed member of the frame, eliminating the need for front downtubes and an engine …

1951 VINCENT COMET RUNNING GEAR The Vincent Comet had frame similar in layout to the V-twin Vincent Black Shadow which included Vincent’s proprietary cantilever rear suspension and Vincent’s Girdraulic forks up front. And, like the big V-twins, the engine was a stressed member of the frame, eliminating the need for front downtubes and an engine …

1960 TRIUMPH TWENTY-ONE HAS BATHTUB STYLING. The British home market had been hungry for cheap transportation after WWII, and commuter motorcycles helped fill that role. But England being…well, England, was wet and rainy and to prevent rust an owner needed to wipe his bike down each night after getting home from work. This was a …

INTRODUCING THE 1938 TRIUMPH SPEED TWIN It’s hard to overstate the significance of the introduction of this bike. Until the moment of its launch, just about every British motorcycle manufacturer was producing mostly big air cooled pushrod singles, but as displacement and performance grew, so did engine vibration. They’d reached the single’s practical limits at …

TRIUMPH DAYTONA IS HOT The Triumph Daytona is essentially the high-performance version of the T100C Trophy 500 twin. Fitted with a new alloy cylinder head mounting two Amal Monobloc carubretors ‘Bonneville-style’, it also had higher compression and hotter cams. The increased the size of the intake valves, and found that they intake and exhaust valves …

CROWDED MARKET The Norton Dominator was Norton’s entry into the crowded vertical twin market, & it was intended to capitalize on the success of, & hopefully steal some sales from, the trend-setting Triumph Speed Twin. When it was introduced in 1949, the 500cc Dominator Model 7 was a handsome enough machine. The new engine was …

1947 TRIUMPH 3T DELUXE BACKGROUND Triumph production reverted to civilian machines in 1946, following the end of World War II. The biggest market that the British motorcycle industry needed to fill was the pressing need for cheap, economical transport to-and-from-work. In response, Triumph announced the new 3T, a 350cc companion to Edward Turner’s 500cc 5T …

1959 TRIUMPH TWENTY-ONE HAS BATHTUB STYLING. The British home market had been hungry for cheap transportation after WWII, and commuter motorcycles helped fill that role. But England being…well, England, was wet and rainy and to prevent rust an owner needed to wipe his bike down each night after getting home from work. This was a …

BSA A65: THE MOVE TO UNIT CONSTRUCTION The BSA A65-A50 twins, the A65 being a 650 twin & it’s smaller sister-bike the BSA A10 500 twin, were the natural result of the trend, then sweeping the British motorcycle industry, to unitize engine construction. Prior, most engine packages were made up of separate crankcase, primary case …

1946 TRIUMPH 3T BACKGROUND As Triumph production reverted to civilian machines immediately after the end of World War II, the company announced the new 3T, a 350cc companion to Edward Turner’s 500cc 5T Speed Twin. The 3T was similar in many respects to the Speed Twin, but also borrowed features from the TRW and 3TW …

Les Harris Bonnevilles Rise from the Ashes The story of the Les Harris Bonnevilles is one of the more fascinating in all of Classic British Motorcycles lore. Such was the reputation of the Triumph name & the enthusiasm & optimism of its most devoted followers that after the 1983 collapse of the Meriden Co-operative-owned Triumph …

EVOLUTION OF THE ATLAS The Norton Atlas evolved from the Norton Dominator line, which had grown since its inception in 1949 from 500 cc to 600cc then again to 650cc with the fire-breathing twin-carb Dominator 650SS. The Norton Atlas was the next logical step. The venerable Bert Hopwood-designed vertical twin that had started out life …

1961 TRIUMPH TWENTY ONE HAS BATHTUB STYLING. The British home market had been hungry for cheap transportation after WWII, and commuter motorcycles helped fill that role. But England being…well, England, was wet and rainy and to prevent rust an owner needed to wipe his bike down each night after getting home from work. This was …

ARIEL RED HUNTER BACKGROUND The 1930s were indeed the Golden Age for the British motorcycle industry. At the time, nearly all of them relied heavily on one basic engine architecture: the air-cooled, pushrod OHV single, and most marques had built their lineup of 350 and 500 singles. As the 1930s opened, Ariel’s product line was …

1964 AJS MODEL 16 BACKGROUND Parent-company AMC secured some lucrative contracts from the British government to build, among other things 80,000 Matchless G3s and G3/Ls. After the war, these became the basis for their civilian middleweight line. As always, every Matchless motorcycle had a near-identical twin in the AJS lineup. This was the AJS Model …

VINCENT RAPIDE BACKGROUND Vincent head engineer Phil Irving was working on some tracings of the firm’s 499cc single cylinder engine in 1936. As things got moved around, two of the tracings lined up roughly in the shape of a V-twin. With a little cajoling, he quickly lined it up enough to see that it would …

1927 AJS MODEL H4 AJS built a fine line of motorcycles in the late 1920s, including side-valve (SV) and overhead valve (OHV) singles ranging in engine size and output. Horsepower was in the single digits across the board. The H4 was a 350cc SV single with advanced features for the day. Special alloys were used …

THE TRIUMPH TWENTY ONE MISSION There are two schools of thought on the name ‘Triumph Twenty One’. It’s either honoring the 21st anniversary of Triumph Engineering, or was derived from the bike’s displacement in cubic inches. Either way, that was just it’s name. It’s model designation was 3TA, and it was Triumph’s entry-level 350 twin. …

THE 1973 TRIUMPH X75 HURRICANE As an interesting aside to the Triumph Trident / BSA Rocket 3 story is the X75 Hurricane. Having insisted on a slightly different 3-cylinder engine from the Triumph’s, BSA wanted to make an impression and show their dealers something exciting for a change, and something that Triumph couldn’t match. There …

ABOVE: The 1960 BSA Gold Star Clubman was a high-performance roadster. The Gold Star also earned major off-road competition cred during its 25-year career. GOLDIE LORE The BSA Gold Star was one of the most successful motorcycles of all time, both in the showroom & on the track. It’s ancient design was outdated almost at …

1959 AJS MODEL 31 BACKGROUND AJS and sister-brand Matchless were late to the vertical twin party. Triumph started it all with the 1938 Speed Twin, the world’s first ‘modern’ vertical twin (aka: parallel twin). It took the world by storm, and suddenly every other British brand had to have one of their own. Alas, World …

ROYAL ENFIELD INTERCEPTOR BACKGROUND Royal Enfield hopped up its 692cc Constellation and created a new model, the 700 Interceptor in 1960, for sale in the US and Canada markets only (on England). They’d just lost their contract to rebadge Constellations with Indian Motorcycle regalia then selling them in the US (or trying) as the Indian …

MY 1979 TRIUMPH T140D BONNEVILLE SPECIAL I own a ’79 T140D myself. It’s pictured above, on display at the Quail Motorcycle Gathering in Carmel CA in 2011. The day after this show I rode it in the Quail Ride, which took us through the hills around Carmel. It happened to be my birthday, and what …

Sweet 1970 Triumph TR6 Trophy, with high pipes (on the other side). THE ORIGINS OF THE TR6 The story of the Triumph TR6 starts, as does virtually every British vertical twin, with the seminal 1938 Triumph Speed Twin. This 500cc cast iron twin started it all & after WWII when civilian production was resumed, it …

1961 AJS MODEL 31 BACKGROUND AJS and sister-brand Matchless were late to the vertical twin party. Triumph started it all with the 1938 Speed Twin, the world’s first ‘modern’ vertical twin (aka: parallel twin). It took the world by storm, and suddenly every other British brand had to have one of their own. Alas, World …

Hinkley Triumph Motorcycles Hinkley Triumph Motorcycles have a rich and interesting history, despite being a fairly young company. The classic Triumph brand led the performance motorcycle market from the end of World War 2 until the late 1960s, when the Japanese absolutely conquered the market. Almost the entire British motorcycle industry collapsed before a relentless …

1936 Matchless G3C Trials. MATCHLESS G3 EARLY HISTORY In the early 1930’s Matchless was enjoying great success with its side-valve & later OHV singles. It was only natural to continue to develop this line, and in 1936 Matchless introduced two new distinct ‘families’ of motorcycles: The “Clubman”, and the “Tourist”. Available in 250, 350 & …

1946 AJS MODEL 18 BACKGROUND Immediately following the end of World War II in 1945, every British motorcycle manufacturer rushed to convert from war production back to making civilian products. Millions of British troops were coming home, and they would all need transportation. But economic times were tough in England after the war, and many …

BSA B50 BACKGROUND BSA built its business and its reputation on big singles. The 350cc and 500cc Gold Star dominated the off-road market from the late 1930s to the early 1960s. By this time of course, the state of the art had moved forward considerably, and the heavy Gold Star couldn’t compete with lighter 2-strokes …

THE VELOCETTE LE – A BEST-SELLER? Immediately following World War 2, there was a pressing need in the UK for simple, inexpensive, utilitarian personal transport to get to-and-from work. Velocette attempted to tap into this market with their radical new “LE” in 1948. LE stands for “Little Engine”, and it certainly was. The 149cc water-cooled, …

1947 BSA C10 BACKGROUND With the exception of their exciting new vertical twin, the A7, BSA’s postwar lineup was pretty pedestrian. They were feeding the biggest market in England at the time: low-cost commuter bikes. While England emerged from World War II as one of the victors, they were shattered economically. So millions of returning …

TRIUMPH SPEED TWIN CHANGES THE WORLD! From their earliest inception through the 1930s, most classic British motorcycles were single-cylinder designs with a few V-twins thrown in for sidecar duty. But the problem with both these configurations is vibration and a lot of it. As bikes grew in displacement and power output and the engine speed …

NORTON NAVIGATOR BACKGROUND Norton has always been known for big powerful bikes like the Manx and the Commando. But they also had a very ambitious line of smaller bikes that they originally built to respond to a change in British motoring law that was announced in 1958. Starting in 1960, first-time British motorcycle riders would …

TANGLED ROOTS The BSA Rocket 3 is something of an anomaly in the history of BSA Motorcycles. Designed by Triumph, (BSA owned Triumph) in their Meriden Plant as the Triumph T150 Trident 750 triple, , and morphed into the BSA A65 Rocket 3, both were produced in BSA’s Small Heath factory. ABOVE: The 1969 BSA …