The KTT was a bike for clubman competitors, and a machine that could give the likes of Norton and AJS a run for their money on the local grass track, and on the esteemed circuits of the Isle of Man. This is quick-fire article on a series of a motorcycle that deserves to go down as one of the best, ever.
Words + Photos: Rich Orriss
The overhead cam K-series produced by Velocette is pretty iconic in the world of old motorcycles. The K series was available in a number of iterations. The touring and supersports models earned the KTS and KSS badges, while the over-the-counter race derived machines took the KTT (Kamshaft Tourist Trophy) stamp. The KTT was a bike for clubman competitors, and a machine that could give the likes of Norton and AJS a run for their money on the local grass track, and on the esteemed circuits of the Isle of Man.
The 350cc overhead camshaft (OHC) Velocette KTT was born out of the vibrant and competitive racing scene of the 1920s, as mechanical innovation really started to develop and test the boundaries of the sport. The Isle of Man TT was one of these test beds, and the spritely KTT was initially developed by the factory as a production racer for the demanding mountain circuit.
The OHC engine was relatively unchartered territory for Velocette, however other manufacturers were quickly proving its worth on the racetrack which ultimately nudged the company in the same direction. Percy Goodman was the man at the drawing board, however things were not that simple… Goodman had to come up with a suitable engine that could fit in the existing Velocette frames which had, up until then, housed compact two-stroke engines.
The result was a narrow and robust crankshaft capable of high revolutions without flexing, and a bore and stroke of 74 x 81 mm – dimensions which were synonymous of all 350cc OHC Velocette’s moving forward.
The official KTT was launched in 1924 at the Olympia Show. The impressive performance of the machine was quickly realised, and once the usual teething problems had been sorted, two race-prepped KTTs were entered into the 1925 IOM TT. Although neither machine witnessed the wave of the chequered flag, the Velocette team were unfazed, and quickly returned to the drawing board to iron out the problems identified from the race.
Meanwhile, a few counties south of the Velocette works, IOM hero Alec Bennett was working away in his newly established and thriving motorcycle business in Southampton. The KTT had appeared in his shop, and he was impressed. The machine was powerful and punchy, and Bennett felt it to be a worthy contender for Junior events. It didn’t take long for Bennett to visit the Velocette factory, and it was later announced that he would lead a team of three riders in the 1926 Junior TT – the other two team members being Gus Kuhn and Fred Povey. Bennett prospered on the Velo, where despite a collision with a bank on the last lap, he took the chequered flag with a 10 minute gap to second place. Velocette also won the manufacturer title with Kuhn and Povey coming in the top 10 – an extraordinary accomplishment for what was considered to be a small-scale firm.
The video below shows the winning TT machine at the Freddie Frith Centenary Parade.
The Velocette team continued to work on the KTT and in 1928 the bike sported the first positive-stop foot gear change on a motorcycle. This was a significant milestone in the journey of the motorcycle. As well as being significant improvement for racing, the setup quickly replaced the hand gear change lever and became the standard for almost all motorcycles to this day.
The Mark 1
The first production KTT, the Mark 1, was sold in September 1928. It was an over-the-counter racer, and capable of well over 85mph on standard fuel, with many riders earning a Gold Star at Brooklands with the bike inhaling alcohol. This was a time when wannabe boy racers were on the scene, and the KTT was therefore a popular choice for those who wanted a tear up.
A 1929 KTT at the Kop Hill Climb
A 1930 KTT that was raced in the 1930 Manx Junior GP by Earnest Foreman
The KTT was a touch above the other bikes in the K-Series, with improved oiling, high compression piston, and AMAC racing carburettor, amongst other engine modifications. The fuel and oil filters were situated on the left hand side of the tank (a nod to the requirements of the IOM TT) and the front Webb girder forks received an extra strengthening strut running from the lower fork link brackets to the front wheel hub. The foot shift was the first in the industry to receive a positive stop with a ratchet return – as seen on pretty much all motorcycles today.
The subsequent iterations of the KTT had a series to denote a modification to the previous model. It should be noted that in the first five years of production, it was simply the “KTT” in factory literature, and the early marks were assigned a number in retrospect.
The Mark II
The 1931 KTT became the Mk II – there was very little difference from the Mk 1, other than the year of manufacturer. The tank was updated to include a “26-28-29 TT Winners” emblem.
The Mark III
In 1932, the KTT was subtly updated with a thicker flange at the cylinder barrel base, and a longer neck to the oil filler. A total of 32 Mk II KTT’s rolled out of the factory, with the the final 14 being fitted with four-speed gearboxes.
The Mark IV
The Mk IV variant was produced from 1933 to early 1935 and featured a new cylinder head (this was modified to a bronze head mid-production to reduce the chances of overheating), a new camshaft, bigger carburettor, new brakes, a four-speed gearbox with Willis positive-stop foot-change, and a bolt-on lower frame rail from the crankcase to the rear axle that improved handling. The Mk IV was not a world beater, but it was fast and handled well – it was the perfect privateer racer which allowed many riders to earn their Gold Stars at Brooklands.
A Mk IV KTT at the Sammy Miller Motorcycle Museum. Note the bronze head.
The Mark V
The Mk V featured the bronze cylinder head that came with the later Mk IV bikes, and with additional oiling improvements. In total, 70 Mk V KTTs were produced. This is a factory supplied race bike that was shipped out to the Isle of Man TT but crashed in practice.
The Mark VI
The Mk VI is somewhat of a unicorn, and was never advertised and never appeared in the factory literature. There are rumours and contradicting reports as to the existence of a Mk VI KTT, however many sources report that there was only one such machine that was ridden by Austin Munks in the Junior Manx GP in 1936, which he happened to win. It is a mysterious beast, however an article over at The Vintagent features a unique piece of research into the forgotten KTT: The Mysterious Mark 6′ | The Vintagent.
The Mark VII
The KTT production line somewhat mellowed after the Mk V, while the competition department focussed on developing race bikes with double overhead cam motors, and it was at this point in time that Velocette started to try and test swinging arm frames. It took a couple of years before the Mk VII KTT appeared in the 1938 catalogue; despite the new tech developed on the factory racers, Velocette kept it simple with a rigid frame and single cam engine, however it was still a capable motorcycle. It was not quite the success that Velocette had hope for, with only 37 machines delivered to the new owners.
The Mark VIII
The advent of the final version – the Mk VIII, was the icing on the cake in the series of the KTT and could be seen as the first ‘modern’ production racer produced by Velocette.
It bore similar characteristics to the competition machines that hero’s of the time such as Stanley Woods and Freddy Frith were using to smash around the TT and other circuits around the continent. The new motorcycle brought with it the technology that Velocette had been working on with their race bikes, which included a swing-arm rear end with two suspension units.
The 1939 IOM TT really showcased the potential of the Mk VIII, with Stanley Woods winning the Junior, and a six Velocette’s taking the top 10 positions. A total of 50 Mk VIII Velo’s had been produced before the Second World War rudely interrupted the winning streak, and it took a few years after the war had simmered down for Velocette to start up production again – it was now 1947.
As it be well known, success in motorsport will always provide a company with that extra boost, and this is exactly what Velocette got with wins in the 1947 and 1948 Junior TT races (at the hands of Bob Foster and Freddie Frith respectively). In 1949 Freddie Frith won every GP race, and the TT. In fact, Freddie did not have to compete in the sixth and last race of the season (the Italian Grand Prix at Monza) having already won the Championship with maximum points.
Freddie Frith at the 1949 Dutch TT
The KTT continued to race into the early 1950s, at which point the technology was starting to appear outdated when compared with the likes of Norton with their featherbed frame Manx models. It would all be reignited however, when at the end of the decade, vintage motorcycle racing flared up, giving the KTT a new lease of like at the hands of enthusiasts such as Ivan Rhodes.
A grand total of 868 Velocette KTTs were rolled off the assembly line in Birmingham and it is to this day considered one of the most sensational and involved 350cc motorcycles of all time, and this accolade is well deserved.
an article by The Girder Club
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