The Classic Motorcycle

Sunbeam Model TT90

Sunbeam’s rare and racy OHV machine has been much in the news of late, with prices realised recognisin­g just how good a machine it was, and remains.

- Words: ALAN CATHCART Photograph­s: KYOICHI NAKAMURA

Like many early British motorcycle marques, Sunbeam’s antecedent­s date back to its origins as a bicycle manufactur­er – though that in fact only came about because cycling was the company owner’s hobby!

Twice Mayor of Wolverhamp­ton, John Marston was a pillar of civic society in Victorian England, as owner of the largest japanning factory in the Black Country. This was a local speciality comprising a form of Orientalin­spired metal finishing then popular for various household tableware and other metalwork, which was duly replaced by enamelling and, later, electropla­ting.

Marston was a keen cyclist, so almost inevitably he began building his own bicycles using his firm’s japanning treatment to impart a finished lustre to them. Apparently his wife Ellen saw one of his early bikes leaning against a wall with its polished frame glinting in the sunshine, leading her to suggest he called his bicycle – The Sunbeam…

The name stuck, so Marston’s Wolverhamp­ton factory was renamed Sunbeamlan­d, and in 1877 he began making bicycles commercial­ly, with an emphasis on high build quality, reliabilit­y and cleanlines­s, imparted by the chain being fully enclosed, and running in oil.

As it did with Sunbeam’s great rival Humber, the advent of the internal combustion engine might have quickly led to Sunbeam branching into motorcycle­s, but in fact John Marston disliked them, and first diversifie­d into cars, in 1899. But he then became uneasy at how much capital was needed to pursue the market for motorised four-wheel conveyance­s, and duly floated Sunbeam cars off as a separate company.

Then, bowing to the inevitable at the age of 76, in

1912 his core business John Marston Ltd produced its first Sunbeam motorcycle, a 350cc side-valve single made almost entirely in-house, followed by a range of 500cc singles, and a few V-twins. These all used chain final drive from the very first – Marston’s late start

meant his bikes missed out the belt-drive era – and like Sunbeam bicycles were built to a high level of quality, invariably finished in a sober black livery with gold-leaf pinstripin­g.

To prove his products’ worth under the most arduous of conditions, Marston sanctioned an intensive campaign of racing, including in the Isle of Man where local rival AJS from the same Midlands town that was a hotbed of early British motorcycle manufactur­ing, made its mark by winning the 1914 Junior TT. But local rider Howard R Davies dead-heated for second place in that year’s Senior TT on a Sunbeam in the marque’s IoM debut, before founding his own TT-winning HRD concern also in Wolverhamp­ton, which in 1928 duly became HRD-Vincent! But in 1920 Tommy de la Hay went one better to record Sunbeam’s debut Island victory – the first of six wins on the Mountain Course during that decade.

In the 1920s Sunbeams were raced successful­ly all over Europe, establishi­ng the marque on the internatio­nal racing map much as the firm’s fourwheele­d equivalent Bentley was doing in cars, while following a similar conservati­ve engineerin­g philosophy matched by high build quality and fast yet robust, reliable performanc­e.

John Marston passed away in 1918, aged 82, just as the First World War ended (during which Sunbeam motorcycle­s were used by the victorious Russian and French Armies), and his business was ultimately acquired in 1919 by Nobel Industries, a British company founded by Swedish chemist Alfred Nobel, the inventor of dynamite, and later founder of the Nobel Prize awards.

Nobel did well by Sunbeam, pouring substantia­l investment into Sunbeamlan­d, including new machinery and extended floor space which allowed annual production to grow to a peak of 2500 bikes by 1930, built by a total workforce of 600 people, all of them high quality machines in keeping with the Marston mantra. For such were the attributes of Sunbeam’s roadster models that they were dubbed the ‘Gentleman’s Motorcycle’, although the side-valve Longstroke and then OHV Model 90, Sunbeam’s most sporting 1920s models, repeatedly won Grand Prix races all over Europe, as well as those six Isle of Man victories, including four Senior TT wins. Comparing that to the up to 35,000 bikes per year produced just across town by the 3000-strong AJS workforce, gives a sense of Sunbeamlan­d’s more focused operation.

De la Hay’s 1920 Senior TT win was obtained with a long-stroke side-valve model, as was his team-mate but bitter rival Alec Bennett’s victory in the 1922 event with a similar bike; the last win for any side-valve machine in the TT races. Similar bikes equipped the various riders from all over Europe, and especially Italy, who rode Sunbeams to successive Grand Prix victories in the early 1920s.

But then in 1923 Sunbeam designer John Greenwood – himself an able rider who scored many successes in Road Trials and the like – produced OHV engines for a works team now headed by newly-appointed competitio­n

“Sunbeam’s refined, gentlemanl­y image, coupled with the proven race-winning performanc­e of its models, made it the machine of choice for Britain’s profession­al classes.”

manager, Graham Walker. But these weren’t immediatel­y successful, leading him to develop an overhead-cam version in 1925, which for some obscure reason was nicknamed the ‘Crocodile’ within the Sunbeam works!

But despite copious testing by a team headed by factory tester and sprint racing titan George Dance, this failed to make an immediate mark, and the design incorporat­ing a vertical shaft and bevel gears like its later rival the CS1 Norton, was swiftly dropped in favour of the more potent and now reliable OHV design.

So from 1926 onwards Sunbeam focused entirely on its OHV dry sump motor, measuring 80x98mm for a capacity of 493cc, with the oil tank mounted on the rear upper frame tube. The cast-iron cylinder and twin-port head were mounted on aluminium crankcases, with a chain driven ML magneto supplying the sparks, a dual oil pump driven off the right end of the crank, and a hand-change three-speed gearbox with oil-bath clutch and chain primary drive. The establishe­d open-cradle tubular steel Sunbeam frame it was mounted in had twin upper tubes sandwichin­g the long, flat-sided fuel tank, which originally had the two front corners chamfered away to make space for the Sunbeam-made Druid-type fork with check springs/side dampers, to turn.

But the 1927 customer version of the works racer, named the TT Model 90 (presumably in reference to the top speed it was guaranteed to attain) had fuel capacity extended to 2½ gallons(11.35 litres) by dint of filling out the front corners of the tank into a rounded shape, which immediatel­y led to it being christened the ‘Bullnose’ Sunbeam – a popular monicker since before the First World War for the well-liked Morris Oxford car, with its distinctiv­e round-topped bullet-nosed radiator.

Success

The Sunbeam factory riders essentiall­y raced speciallyp­repared versions of the customer Model 90, and during 1927-30 became almost unbeatable at the highest level of GP racing. Success flowed readily to them in the 500cc class (the 350cc counterpar­t was never so successful, perhaps because all the resources of a relatively small racing department were lavished on the Senior machine), and in the hands of first Graham Walker and then

Charlie Dodson several Grand Prix victories, as well as two more Senior TT wins, came their way. In the first of these, in 1928, Charlie Dodson predated Mike Hailwood by nearly 40 years in winning the Senior TT after crashing and remounting to pass his former team-mate Graham Walker’s broken-down Rudge on the last lap for a sterling victory. After a true saga like that, George Formby’s No Limit movie doesn’t seem so unlikely after all – and the ‘Rainbow’ machines the Lancashire Lad rode in the film had an uncommonly similar name to ‘Sunbeam…’ !

The diminutive Dodson repeated his Senior TT win in 1929, having also taken victory in the 1928 German and Belgian GPs, while other ’Beam riders scored multiple wins in the German GP at the new Nürburgrin­g, the Circuito del Lario aka the Italian TT, and the Italian GP at Monza, where future Alfa Romeo and Auto Union GP car racer Achille Varzi, four times a Sunbeam team member in the Isle of Man with a best finish of seventh in the 1926 Senior TT, smashed the lap record in winning the 1929 race on a Model 90. But the effects of the Depression were as keenly felt at Sunbeam as elsewhere in the British motorcycle industry, and 1930 was the last year in which a works team was run.

Sunbeam’s refined, gentlemanl­y image coupled with the proven race-winning performanc­e of its models, made it the machine of choice for Britain’s profession­al classes, and that included Scottish solicitor Ralston Dunlop from Ayr, whose interest in Sunbeams began with Sprint models, which he raced with some success in the mid-1920s. At the beginning of 1927, he arranged with the Sunbeam distributo­rs in Glasgow to obtain a Model 90 for that season, with the proviso that it must be “a good one”. Graham Walker took matters in hand, and arranged for this bike to be fitted with a two-inch (51mm) inlet valve, while retaining the stock 1⁄in/43mm exhaust, the two set at an included angle of 90° in the hemispheri­c combustion chamber. Sunbeam was the first manufactur­er to race machines fitted with hairpin valve springs, duly fitted to this motor.

After receiving a final ‘workover’ by George Dance, the bike carrying Frame no. D2023 and Engine no. N1014 was first registered on March 29, 1927, with registrati­on number GD 6247 – strangely, a Kent plate from the southeast corner of England – and was widely believed to be the fastest Model 90 in the country at the time.

After a successful series of Sprint outings with his new bike, in July 1927 Dunlop raced the Sunbeam in the Scottish Speed Championsh­ip on St Andrews Beach, where he won the 10-lap/20-mile 500cc race, broadsidin­g to victory against such rivals as future GP star Jimmie Guthrie on a works New Hudson.

In 1928 Dunlop raised the compressio­n from 9:1 to

10:1, and fitted the now compulsory Brooklands exhaust cans, but as he explained in a 1941 letter to a later owner of the ’Beam, “While possibly faster, the bike now had a habit of shaking to pieces! The valve overlap was such that there was very little power below 3000rpm. I was

“In the 1920s Sunbeams were raced successful­ly all over Europe, with riders of many nationalit­ies favouring them.”

running other machines in trials at this time, and I used the ‘90’ on the road hardly at all. I am ashamed to say it did a spell on a dirt track before I parted with it.” Shame, indeed! Stepping back from racing, Dunlop removed the AMAC twin float 1⅜-inch (35mm) carb it had been supplied with, and fitted a smaller one for road use in Scotland. He followed the 1928 Scottish Six Days Trials with the Sunbeam, despite it not being fitted with a kickstart, so had to be bump started in to life every time.

The Model 90 then migrated south to Rawland Smith, a London dealer in Hampstead NW3, from where it was bought in February 1929 for 100 guineas by Leslie Stiles, who had read about the Sunbeam in the Motor Cycle weekly, and how “it had won the speed event at St Andrews, and was reckoned to be the best bike of the day.”

Stiles built it up and met with a reasonable amount of success at local events, running with short copper straight-through exhaust pipes, before selling it at the end of that year to a dealer in Bushey, Herts. It was soon purchased by a Frederick Hoffmann, who used it hard but unlovingly for the next two years, before it was acquired in February 1932 by Arthur “Torrens” Bourne, editor of The Motor Cycle magazine for 25 years until

1951, and a director of the publishers, Iliffe, until 1967. In short, he was a substantia­l figure in the golden age of British motorcycli­ng, who wrote under the “Torrens” pseudonym.

Bourne bought the Sunbeam privately in February 1932, and appears to have ridden it regularly, featuring it in a series of 30 weekly articles during 1934-35 on “Overhaulin­g a Seven-year-old-Thoroughbr­ed”. He intended to restore it when he retired, and in fact dismantled it ready to do so, but by 1973 concluded that arthritis had got the better of him, so decided to dispose of it.

Fulfilling a promise made in 1941 to Ralston Dunlop of offering him first refusal if ever it was ever sold, he wrote to his law firm, but was advised Dunlop had passed away in 1959. So instead, the Model 90 was acquired in November 1975 by a Mr Thomas in Carmarthen, Wales, who then sold it in 1979 to Bill Page in Yorkshire, who described it as “one of the most unmolested examples of the Model 90” he’d yet seen. Page restored it sympatheti­cally, and sold it to the Anthony Blight Collection in Cornwall, before it was eventually bought in 2002 by its current owner, investment banker John M H Summers, then 39 years of age. He had the engine overhauled in 2006 by Rob Kucinskas at Alec Jay Motorcycle­s in Addlestone, since when it’s been ridden regularly as well as appearing at many Brooklands events, and also in the Jersey Motoring Festival’s Moonlight Sprint in 2009.

Having thirsted to sample a Model 90 Sunbeam ever since I rode my chum Dennis Wright’s only slightly less potent Model 9 factory prototype at Brands

Hatch almost 40 years ago, it was a pleasure to take up John Summers’ offer of a spin on his beautifull­y fettled and regularly ridden ’Beam – not on a race track this time though, but around the leafy lanes of rural Warwickshi­re.

First, though, I took a long, lingering look of appreciati­on at what is surely the most elegant, understate­d but supremely potent-looking package on two wheels from the vintage era – a true visual symphony of speed. Then followed careful mental notes while John explained the clutter of controls on the low, flat, slightly pulled back handlebar that you can’t help but adopt a stylish, sporting stance in grasping – though the riding position is quite close-coupled, and the footrests are higher and set further back than usual on a vintage-era bike – with a 55-inch/1400mm wheelbase, the Sunbeam isn’t as rangy as some of its contempora­ries I’ve ridden, and despite the excellent grip from the modern ribbed front 3.00x21in Avon Speedmaste­r Mk.II and rear 3.00x19in Heidenau rubber, the Sunbeam displayed no ground clearance problems in enthusiast­ic cornering, even from the low-set twin large-diameter exhausts.

The left ’bar is the most busy, with the valve lifter lever at its end, the clutch inboard of it, then the supplement­ary oil lever you must remember to work every so often with your forefinger to add a little lube to the crankshaft assembly. The piéce de résistance is the magnificen­t bulb klaxon horn mounted on the left of the steering head, for both visual effect and practical warning of the Sunbeam’s imminent presence, just in case someone didn’t hear the healthy crack from the twin exhausts.

On the right, the longer lever is the choke, the shorter one the ignition control, and the front brake lever works the surprising­ly effective seveninch/178mm single leading-shoe drum – combined with the slightly larger eight-inch/203 mm SLS rear, this

Sunbeam-built duo actually worked much better than I was expecting, even if you must still make use of the valve lifter in a panic stop. Still, I wonder why it took many other manufactur­ers so much longer to develop brakes that worked as well as these – though it’s worth pointing out that using the front brake overly hard back then apparently caused the somewhat frail Druid fork some strife, with Dodson particular­ly suffering collapsed front end on more than one occasion, despite his light weight.

No kick-starter on this racer-for-the-public-highway, so firing it up dictates a modicum of retard, back on compressio­n and engage the valve lifter, then run alongside, start the engine turning over, drop the lifter, there’s a sudden crack of the neo-Brooklands fishtail baffle-less exhausts–and you’re away.

So far so good, but now the problems begin. First off, bottom gear is really low, so it’s quickly time to change into second – so time too to relearn the technique of changing gear, which becomes second nature with a foot-change. The Sunbeam’s hand-change lever is mounted on the right side of the tank – down for down, up for up: nothing could be simpler – except that your right hand is also supposed to be working the throttle! Intrepid aces of the vintage period doubtless worked hard to perfect their left-hand, across the tank, clutchless gearchange­s, but to the modern mind, accustomed to having to cope with nothing more demanding than rememberin­g which foot to use, such unfamiliar technique is out of the question, especially on someone else’s such valuable machine.

Racy cams

A painfully slow change into second therefore ensued, with consequent falling off of revs, but here the Sunbeam itself decided to help out the dilettante it was obliged to cart along Warwickshi­re lanes for an afternoon. There’s a superb spread of usable power and torque from as low as – I’d guess – 2000rpm (there’s no ‘revmeter’) up to a probable peak of around 6000 revs, which enables you to get away with very few gearchange­s, and not much slipping of the clutch.

Just get it into top (third) gear, and you can drive cleanly out of most corners with only a fractional loss of accelerati­on to mark using too high a ratio. This is somewhat surprising considerin­g the race spec motor, still complete with the soup-spoon sized inlet valve fitted when new, and the racy cams which helped make the bike a race-winner in its debut season on the sand.

After a few miles I began to get the hang of things, though a clean change down from third to second while braking for a tighter turn still eluded me from time to time. However, as I gained in confidence, the other limitation­s of the state of the art in 1927 grew in importance. As you accelerate hard out of a second gear, off-camber corner, the square section of the rear tyre, abetted by the high pressure used, allows no warning of a sudden breakaway, and a hefty slide (out of view of John Summers!) soon tempered my enthusiasm.

Also the rather frail-looking Druid girder fork tried to tie itself in knots when faced with a fast sweeping bend with a bump in the middle. Fortunatel­y, I wasn’t going too fast, so that the resultant tank-slapper was remedied by simply easing off. Riders of the time must have needed a strong will and plenty of muscle to ride these machines at racing speeds back then.

But in other respects this 90-year old bike felt unexpected­ly modern to ride, breezing comfortabl­y along at up to 70mph as shown on the digital speedo John has strapped to the handlebar. The tank pads allowed me to grip the slim fuel tank with my knees for added confidence in bends, and the leather-topped Brooks Supple Seat’s taut but sufficient springing delivered a modicum of riding comfort along the way.

The rigid frame inevitably meant that the Sunbeam’s rear end skipped slightly in the air over the worst of the Warwickshi­re roads’ bumps along the way, but this was a capable and exhilarati­ng ride which I’m very grateful to John Summers for allowing me to experience. Despite being the last flat-tank model to win a Senior TT, the gruelling 250-mile/400km-plus Grand Prix races of the day would have been easier to tackle with a machine as capable as this one, within the context of its era.

It’s believed that less than 100 (possibly as few as 50) Bullnose Sunbeam Model 90s survive today. Their owners are very fortunate – especially if, like John Summers, they also have a vintage Bentley sports car to keep their Sunbeam company in their motor shed!

Head to classicmag­azines.co.uk to preorder your next issue of The Classic MotorCycle. We will send it directly to you – easy! No need to don a face mask and nip out to the shops, hurrah! www.classicmag­azines.co.uk/pre-order-tcm

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 ??  ?? 1: The heart of the matter – the Sunbeam’s tall, powerful engine.
1: The heart of the matter – the Sunbeam’s tall, powerful engine.
 ??  ?? 2: Hairpin valve springs were
specified.
2: Hairpin valve springs were specified.
 ??  ?? 3: Square ML magneto was top level equipment.
Right: Wide handlebars encourage pushing the Sunbeam down
into corners.
3: Square ML magneto was top level equipment. Right: Wide handlebars encourage pushing the Sunbeam down into corners.
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 ??  ?? 1: Bullnose tank can be seen from this angle.
2: Twin exhaust giving the model a lovely symmetry.
3: For reasons unclear, the Sunbeam wears a Kent registrati­on.
4: There’s a modern digital speedo fitted – not a bad idea, as one could easily, inadverten­tly pick up speeding fines on this machine!
5: There’s a seven inch front brake, eight at the rear.
1: Bullnose tank can be seen from this angle. 2: Twin exhaust giving the model a lovely symmetry. 3: For reasons unclear, the Sunbeam wears a Kent registrati­on. 4: There’s a modern digital speedo fitted – not a bad idea, as one could easily, inadverten­tly pick up speeding fines on this machine! 5: There’s a seven inch front brake, eight at the rear.
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 ??  ?? 4: The best vintage era 500? Well, there aren’t many
(any?) better…
4: The best vintage era 500? Well, there aren’t many (any?) better…
 ??  ?? 3: Alan Cathcart gets to play 1920s racers.
3: Alan Cathcart gets to play 1920s racers.
 ??  ?? The original logbook, detailing the motorcycle’s impeccable history.
The original logbook, detailing the motorcycle’s impeccable history.
 ??  ?? 2: Footrests are set
quite a long way back, for the period.
2: Footrests are set quite a long way back, for the period.
 ??  ?? 1: Extra friction dampers the Druid-type side
spring forks.
1: Extra friction dampers the Druid-type side spring forks.
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 ??  ?? 1: For a machine fast approachin­g 100 years old, performanc­e is remarkable.
2: The Scottish Speed Championsh­ip of 1927. Number one is the winner, Ralston Dunlop, on this machine.
3: Three views of the superb, original twin-float AMAC.
1: For a machine fast approachin­g 100 years old, performanc­e is remarkable. 2: The Scottish Speed Championsh­ip of 1927. Number one is the winner, Ralston Dunlop, on this machine. 3: Three views of the superb, original twin-float AMAC.

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