Like many students of Classic era road racing, I’ve always wondered what the BSA MC1 250 was like to ride. Now, thanks to former racer and member of the prestigious AMA Motorcycle Hall of Fame, Sammy Miller, I’ve finally sampled this mystery motorcycle. This thoroughbred racing motorcycle could very well have been the one that could have prevented BSA’s ultimate demise. It was indeed a motorcycle ahead of its time and should have spawned road-going versions that would have been of the like that the world had never seen. If only the management of the once largest motorcycle manufacturer had the foresight...
The BSA is visually deceptive, because the massive seven-gallon fuel tank you must drape yourself around when you hop aboard makes it seem much bigger than it really is. In fact, the whole bike is low and surprisingly compact, with steeply dropped clipons – actually, bolt-ons, to the bosses emanating from the side of the ‘inside out’ steering assembly – which encourage you to tuck away behind the mesh flyscreen, using the deep cutouts in the front of the tank to find space for your hands when negotiating a tight bend. Further back, you must slide rearwards in the slim seat to work your knees into the indentations in the rear of the tank in order to obtain a more windcheating stance – although I preferred to sit slightly further forward so as to brace my knees against the ridges of the cutouts, for greater purchase when changing direction.
Firing up the BSA is child’s play – take three paces, drop the light-action clutch, and you’re away. This would have been an ideal bike for the push-starts to races pertaining back then, not only for the ease of starting, but also by the way the engine picks up revs so relatively fast – you hardly need to work the clutch to get it moving off the mark. This was a surprise because of the oversquare engine dimensions, but while it drives okay out of a slow bend, it’s not till the needle on the counter-clockwise Smiths conical rev-counter reaches the 7,000 rpm mark that the MC1 comes alive – so you do need to clutch it hard to get meaningful drive, noting as you do so that an engine when you rev it at rest has the typically lumpy feeling of a single, sounds more and more like a twin as the revs mount. As it does so, the BSA changes its nature faster than a chameleon its colour as the twincam motor really takes off, with the tacho needle heading purposefully for the 11,000 rpm redline, though you can feel it peak out at a little over ten grand. Vibration is relatively contained – I was expecting it to be much worse than it is after hearing about all the things that kept breaking on the engine thanks to the vibes encountered on the dyno during the development process. But shifting up on the one-up right-foot gearchange leaves you around 3,000 revs lower down the powerband, thanks to the four-speed Burman gearbox’s well-spaced ratios – really, this is a bike crying out for a fifth gear ratio to close everything up better, and keep what’s obviously a pretty peaky motor on the boil. As it is, the gearshift action is rather stiff and frankly agricultural-seeming – it’s not very nice to use. The whole transmission seems rather vintage in nature, out of kilter with the otherwise modern-feeling nature of everything else.
Same thing with the handling, which is light and responsive, and while I didn’t ride the BSA hard enough to agree or disagree with Geoff Duke’s positive assessment of the steering, it did change direction well, and seemed very precise in the way it could be positioned in a turn. By the standards of the early ’50s I guess the suspension felt pretty compliant, though the cantilever rear shock was quite stiffly sprung and so tended to skip over ridges and concrete joints in the airfield test track. However, the leading-link fork felt pretty compliant compared to the girder forks of some of its Velocette, Excelsior and other period rivals, even if I wasn’t cornering it hard enough to run the risk of grounding the exhausts either side, as Geoff Duke did the first time he rode the MC1 at Oulton Park, leading him to stiffen the front springs.
But if all that felt pretty modern, where the BSA’s handling let it down was the ineffectual braking delivered by the double-sided eight-inch front and seven-inch rear drums, both mere single leading-shoe units. Neither of these offered any real bite, and the front faded noticeably after several hard stops from speed on the airfield track. A true tonne-up bike like the BSA deserved much better even back then, and I’m surprised that Roland Pike, himself a skilled racer, didn’t insist on this. However, his TT and short circuit success was gained aboard modified prewar bikes which probably suffered from the same lack of stopping power, so I guess that explains it.
But the BSA was certainly on a different level to anything else Made in England at the time for the 250GP class. After riding it, I’m convinced that, provided it could have been made reliable, the MC1 would have had something to offer GP privateers in terms of performance. It would have been competitive up until the arrival of the Japanese multis in the 1960s – and even after that, at National level. The works 250 Mondial I used to own which won the 1957 World title probably accelerated better – it kept pace with the lighter, later Aermacchis I raced it against, thanks to the extra top end power of its high-revving motor, though it may not have been as fast on top speed as the low-slung BSA, once its dustbin fairing was removed from 1958 onwards. And the BSA definitely steered better than the relatively top-heavy upright-cylinder Italian bike on which Mike Hailwood won so many races in 1959-60. So, yes, after riding it, for sure BSA management made a mistake in cancelling the MC1 project, simply because Bert Hopwood and Doug Hele were honest enough not to promise them that the bike would win first time out. And equally, they lost the chance of producing a lightweight streetbike that would have stood out from the crowd in terms of performance, and allure. Losers all around, that’s what the BSA bigwigs truly were...
What Might Have Been….
The MC1 was conceived by Bert Hopwood, who in the immediate post-WW2 era worked as an engineer at Birmingham-based Norton, for whom he created the legendary Dominator parallel-twin. This caused him to be headhunted by a much bigger company on the other side of Britain’s Second City, and in May 1948 Hopwood, 40, became Chief Engineer at BSA. There, he was eager to
use BSA’s massive resources, both technical and financial, to develop an innovative new generation of customer products. And in 1949 he roughed out the concept of a 250cc single with a horizontal cylinder, and four radial valves operated by two short, chain-driven, vertically arranged overhead camshafts positioned in an inverted vee, and connected by bevel gears. That same year, Hopwood’s assistant at Norton, 30-year old Doug Hele, followed him to BSA, and in 1950 was commissioned by him with putting this concept into metal as the prototype for a family of road bikes, with a possible view to going racing with the result in the Lightweight TT in the Isle of Man.
With a complete free hand to design the bike as he saw fit, Hele took the Hopwood layout as his starting point, retaining its overall architecture with the air-cooled cylinder inclined slightly upwards to help deliver a reduced frontal area. Hele also rearranged the camshaft layout, retaining the inverted vee layout, but rotating the shafts so that they now ran transversely across the engine, thus allowing cooling air to flow beneath their arch, over the top of the cylinder head. This also permitted fitting twin Amal GP carbs and separate but slender twin megaphone exhausts were used.
Considerable care was taken in designing the cylinder head, and to do so Hele called on the services of Donald Bastow, the former Bentley and Lagonda engineer who was, by then, in charge of the BSA Group’s Experimental Department. A short forged conrod was used to reduce the engine length, which carried an eventually forged three-ring piston, that delivered a 10.1:1 compression ratio in producing the best power output obtained during the project’s five years of development. And to provide sufficient inertia while also obtaining adequate clearance between flywheel and piston by using the short rod, a Guzzi-type outside flywheel was mounted on the left. Strangely, on such an advanced design, a separate Burman gearbox with chain primary drive was employed – and a four-speeder at that, rather than a unit-construction five-speeder. This came in spite of the implicit recognition that such a short-stroke engine would have an appetite for some serious revs.
The design of the MC1 engine was completed over the winter of 1950/51, and while the first of the three engines eventually made was being constructed in BSA’s Small Heath factory, Hele set about designing a chassis to accommodate it. As revolutionary for its time as the engine, this was essentially an early forerunner of today’s twin-spar aluminium frames in terms of wrapping round the engine to link the steering head directly with the swingarm pivot, but was made from Reynolds 531 chrome-moly steel tube.
The BSA’s modern-style rear suspension layout featured a chrome-moly cantilever swingarm pivoting on the rear of the chassis, and operating a single Girling coil-spring shock mounted under the seat, within a hollow in the oil tank, and attached to a brace welded to a cross-tube on the duplex frame.
The front suspension was just as unusual, a so-called ‘inside-out’ design that was essentially a reinterpretation of the existing (and patented!) Earles leading-link fork. This had been developed so as not to infringe the Earles patents (which BSA would otherwise have had to pay to use), with future production use in mind, and essentially delivered a less flimsy and more compliant front end structure than the girder forks by then seen as outmoded, and the early telescopics just then being introduced. All in, but with no streamlining, dry weight was a respectable 113 kg.
The Hele-designed engine was only run for the first time on the dyno in February 1952, delivering 28.6 bhp at 9,000 rpm by the end of its first run - by which time Roland Pike, a gifted rider/engineer had joined BSA. Roland was recruited by Hopwood in 1951, and stayed at BSA until 1957. On joining, he was put in charge of supervising development of the MC1 project, which to say the least was fraught from the beginning, as Pike told me when I visited him in 1982 at his home in Walhalla, South Carolina.
But run it did, eventually, with the complete set of copies of MC1 test records, engineering reports, company memos and riding data which Roland Pike showed me – they’re now in the possession of Sammy Miller – revealing that by October 1952 the motor was delivering 31bhp at 9,500 rpm, running on Amal TT9 carburettors, rising to 32 bhp at the same revs using Amal GP racing carbs. However, reliability was the issue, and a second, modified, engine was built in February 1953, after which dyno work continued though that year gradually trouble-shooting all the problems, with a third engine built later which eventually produced 34 bhp at 10,250 rpm, although not altogether reliably. Early in 1954 the one and only complete bike made by BSA had been assembled, using engine No.2.
The MC1 project ended after a guarantee to the BSA management wasn't inevitably forthcoming from Hopwood and Hele to win the big Hutchinson 100 National meeting held at Silverstone on October 1st, 1955 that it was entered in. The solitary bike built was consigned to a shed in BSA’s Small Heath factory. It was exhumed from there, dusty and neglected, for John Griffiths to acquire it in 1971 for the Stanford Hall museum – just before BSA went bust, otherwise it would surely have been scrapped. On his death a decade later it was purchased by Northern racing enthusiast Paul Ingham, who restored it to the present high standard it’s in today, and rode it several times in public at Aintree and Oulton Park before selling it to Sammy Miller in 1987 for display in his eponymous Museum. The BSA has remained there ever since on public display, but like all the Miller motorcycles has been regularly exercised in public, including in the Isle of Man TT Parade – so, it visited the Mountain Course, eventually as a reminder of the eternal conundrum. Could it, might it, have been a great British world-beater? We’ll never know that, either.