Triumph 6/1
Rare twin
History records the 649cc parallel twin design by the celebrated Valentine ‘Val’ Page in 1933 as anything but a sales success. In fact, after three years in the catalogue, only about 100 were reputedly built. Thus the Model 6/1 – an unimaginative title if ever there was one – is so rare that most Triumph aficionados are unaware of its existence.
Mention Triumph twins and almost universally we think of the Speed Twin, designed by Edward Turner four years later. Coincidentally, or perhaps not, Turner and Page had worked together at Ariel from 1928 to 1932, where Page was the senior man in the design department. Ariel at the time had a solid range of well-built singles, and by 1931, the Turner-designed Square Four, but Triumph on the other hand, was struggling with out-dated designs and a shortage of cash.
Triumph actually had some history with the parallel twin concept, having used a bought-in 616cc Bercley engine in 1909 and their own 600 side-valve with a 180 degree crank in 1913. This one used split big ends with a horizontally-split crankcase cast in aluminium.
Towards the end of 1932, Triumph managed to poach Page from Ariel, and he was given free reign to breath life into the range, at first concentrating on the existing singles. While working on the prototype 500cc Ariel Square Four with Turner, they had both keenly observed that removing one of the gear-together crankshafts, and this creating a 250cc parallel twin, resulted in a fairly orthodox and sweet-running 250 twin. The concept went no further at Ariel until much later, but Page kept the thought while at his drawing board at Triumph. The result was the 6/1, a long stroke (70 x 84) 649cc overhead valve twin with a 360 degree crank, which was primarily envisaged as a sidecar hauler. The engine itself was an iron top end on the vertically-split crankcases, with separate cylinder heads for lapping in to cylinder spigots with no gasket. Rockers were exposed and lubricated by grease gun. The single camshaft sat at the top rear of the crankcase, like the later BSA and Norton twins, with the four pushrods also running in a tunnel at the rear of the cylinder block. The Lucas Magdyno was gear-driven in a train of four gears in the timing case.
Down below sat some departures from the usual British thinking. The flywheel was external, housed in the primary chain case behind the engine sprocket, which drove the clutch directly via double helical gears which were quieter in operation than single helical gears but were very expensive to machine and required careful set up to obtain perfect loading. This of course meant the engine had to run backwards, which was unusual then but commonplace now. It also dictated that the engine had to be shifted across the frame to the right in order for the final drive chain to line up with the rear wheel sprocket. This created a problem in that the left hand cylinder, which was largely masked by the front mudguard, would often run hot. The original design had the oil tank contained within the crankcases with a single-plunger pump, but this was later moved to the conventional position on the right side below the seat.
Initially, the 6/1 was fitted with a hand-change gear-shift for the four-speed gearbox, which became foot-change for the second sales season, 1935. As there was no primary adjustment necessary, the gearbox was bolted to the rear of the crankcase. More sidecar-slanted thinking saw the front and rear brakes (both fairly large 8 inch jobs) linked.
The front brake handlebar lever operated only that brake, while the foot pedal on the left side brought both brakes into play. The rear brake could also be locked for parking by a ratchet-operated plunger sitting at the rear of the primary chaincase.
The frame was a fairly massive double-cradle affair, unique to the model and contributing to the all-up weight of 412 pounds (187 kg). The front forks were 1.5 inches longer than Page’s 5/2 500, also unique to the 6/1 model. Under the sprung saddle was a steel toolbox, with a luggage carrier on the rear mudguard.
Prior to the general release, the prototype 6/1 was given a rigorous workout. An entry was placed in the 1933 International Six Days Trial held in Wales with Triumph Sales Manager Harry Perrey (who was also a noted stunt man) at the controls of the outfit which was fitted with a
Gloria sidecar. Commendably, Perry was on track for a Gold Medal until the final day, when a front tyre puncture cost him time and he finished with
Silver. Following the ISDT, the same outfit was taken to Brooklands where, ridden by a team of three riders including Perrey, it covered 500 miles in
498 minutes under ACU supervision, earning the prestigious Maudes Trophy for 1933. In an attempt to grab the trophy put up by The Motor Cycle magazine for the first British 500cc ‘multi’ to cover 100 miles in one hour, Triumph even built a supercharged version of the 6/1, with the bore reduced to 63mm. This produced a quite remarkable 47 horsepower, but teething troubles beset it, and by the time Triumph got it right (and recorded a speed of 116 mph at Brooklands), New Imperial had beaten them to the prize. ‚
And so the 6/1 – at £76 (1936) the most expensive machine in the Triumph catalogue – went on sale in 1934. A sidecar would set the buyer back a further £17/10/-. The 6/1 was also listed as a solo with different gearing, but a number of factors, including lack of ground clearance, the overall weight, and the hand-change gearbox meant few were ridden without a chair attached. A foot-change gearbox was actually offered for the final year of production, but this was a fairly clumsy mechanism bolted to the top of the gearbox.
In reality, the 6/1 missed its mark because the sidecar itself was in rapid decline as small cars (including Triumph’s own Super 9) came onto the market. In the final year it was catalogued, 1935, the price was dropped to £70 but this was not enough to save the 6/1, nor Val Page’s position with the firm. In fact, the whole company needed saving, and as 1936 dawned, the entire future of motorcycle manufacturing at the Coventry factory was under serious threat. A receiver was appointed by the bank, but luckily, the enterprising Jack
Sangster intervened and purchased the company. The car side was quickly sold off, but the parallel twin concept clearly had legs, as Edward Turner would soon demonstrate with the Speed Twin. Page himself moved on to BSA where he designed a fleet of new models including the inspired Empire Star – forerunner of the Gold Star series.
Under Turner, Triumph also prospered and with the Speed twin, the company got it exactly right and the motorcycling world changed forever. Given the strict limitations of his employment contract however, Page’s 6/1 was not a bad effort, and its sales failure was more to do with the ill health of the company itself.
Back from the dead
Today, the 6/1 is a rare bird indeed, and our featured motorcycle an especially well presented example.
“In fact, the whole company needed saving, and as 1936 dawned, the entire future of motorcycle manufacturing at the Coventry factory was under serious threat.”
Owner Noel James acquired the 6/1 after protracted negotiations, as he explains. “In 2010 I heard about a 40’ container full of classic motorcycles for sale including BSA, Norton, Royal Enfield, and the Triumph 6/1. After several phone calls I tracked down the right person to talk to. The collection belonged to a gentleman from Avenal (near Seymour, north of Melbourne) who had sadly passed away and what was in the container was the contents of his shed. John, the person I was dealing with had previously tried to sell the complete collection as a job lot but had no takers. It was then decided to sell the contents of in small lots.
“Two of my brothers and I drove to where he was and had a look at the 6/1. The bike was completely dismantled and all mixed up with a great ‚
assortment of other bikes which were in a similar state. I ascertained there was enough parts to build two bikes, plus spare bits and pieces. After a discussion with my brothers we thought we’d have a go at buying it. The sale was a silent auction – after some bidding I received a call from John saying mine was the winning bid. So we travelled the 90 minutes to where John was and loaded up a tandem trailer full of 6/1 parts, unloaded in my shed and started to figure out the jigsaw puzzles I’d just bought.
“Firstly I bolted together one bike as best I could to see how it all went together keeping the best of the parts for myself. After taking that bike to several swap meets I ended up selling it to Lionel Simpson from Dubbo. After that I continued the rebuilding of the bike I kept. I was lucky enough that most of it was there although completely apart; the only item intact was the gearbox. Missing parts were front mudguard, mufflers, 3rd brush generator, and the amp meter. After talking to Bryce Findlay he suggested I call Bryan Grace from S.A. which I did straight away and we spoke for about an hour about 6/1 Triumphs, he also having one being a 1933 with a hand change. A great friendship was cemented that night as we managed to swap parts; me receiving a front mudguard and generator and he received rear wheel and other parts he copied and returned back to me. Unfortunately Bryan passed away early this year and he is sadly missed. “Now I had pretty much everything so restoration began in earnest. The heads were done (one for each cylinder), crankshaft ground, the steel con rods white metaled, wheels, fuel tank, and mudguards chromed. Forks were refurbished by Peter Gaggioni, all painting was done then assembly begun. All this was done over a period of years as I work full time. One thing that had me tricked for a while was the oil system, being used to the normal Triumph practice of oil tank gravity feed to the engine oil pump, through the engine and back to the tank. On the 6/1, there is an oil reservoir in crankcase under the crankshaft. The small tank on right hand side is oil cooler. There’s a single plunger oil pump in the crankcase oil reservoir pumping oil to the oil cooler and back to engine crankshaft, so the cooler is pressurised – opposite to normal. If you don’t fill the oil cooler to over flowing you don’t get oil pressure.”
“I took the bike to Jim Brownlee for a set of pipes and mufflers to be made which are spot-on original. After completion I rode in a 2-day rally covering 145 miles with no problems, although I fitted a bigger main jet after I came home. Compared to my 1938 Speed Twin the 6/1 is heavier and not as free revving and the gearbox with the bolt-on foot change is very slow. I was attracted to this model because it’s the first overhead valve vertical twin that Triumph made. I already had a 1987 Bonneville being the last Harris Bonneville sold by Union Jack Motorcycles which I purchased new from Phil Pilgrim in 1989. Therefore I have the first Val Page twin produced for three years only (mine being a 1936 model), the Turner 1938 Speed Twin, and the last Triumph of Turner’s design, a 1987 Bonneville. Three of a kind!” Noel is keen to hear from anyone with interest in the 6/1. He can be contacted by email on: jamesnaj@bigpond.com
n“I was attracted to this model because it’s the first overhead valve vertical twin that Triumph made.”