The BSA C15 was in trials spec according to the owner and an almost wrecked field bike according to my eyes. “Needs a bit of a clean, don't it, mate,” was the vendor’s explanation for the terrible state of the OHV single. “There're several boxes full of chassis bits and, oh, the lights are over there. Worth a grand of anyone’s money, eh?” Eh, no chance of that, I thought. A feeling reinforced when he eventually kicked the engine into life. Short of a metal band I'd never heard such a racket coming from the top end of a motorcycle.
I poked around in the boxes, finding several tanks, guards, wheels, frames, etc, even though most of them didn't look like they came from a C15. There was a dearth of engine parts, which might turn out expensive given the mechanical noises and way the bike lurched up the road. Back at the house, the owner gave it his best try, “The mill's in trials spec, the full 20hp motor, mate, you don't get many like that, these days. I could come down to £800 for cash.” In a fair, rational world he would've been pushing his luck asking for a 100 notes but the classic scene meant that money talked loud and there was always the chance that some Henry would turn up with more money than sense. We agreed on £525 if he'd deliver the stuff in the converted ambulance that was loitering in his drive way. The lunatic proceeded to part the doubting before us by turning on the siren and keeping his foot flat on the floor. I've never done fifty miles on four wheels so quickly and it's not something I want to repeat.
The C15 was introduced in 1958, was for that period a relatively modern, unit construction OHV 250cc single. In various forms, with lots of detail changes, it ended up as the 1970 B50SS, a machine that mirrored the decline of the British motorcycle industry by developing a mild, relatively reliable bike into a fearsome device that was lucky to last 5000 miles. The basic problem with these singles, as with the twins, was vibration and the larger and higher tuned they became the more vile was their basic nature.
I'd had some experience of the C15 in the past, and saw my purchase as a cheap way back into British motorcycling. The first thing I did was to set the valves, points and carb as the manufacturer had intended. That lessened the rattles to an acceptable level and made starting a mild exertion rather than leg or back breaking. If the timing’s out slightly these motors can give a hell of a kickback out of all proportion to their size and power. Servicing is a 500 mile affair.
I rode it like that for a while, just to suss out that it was worth investing some time, money and energy in the chassis. The motor was gentle, lacking any real power band but running between 10 and 60mph in fourth without any problems. The engine buzzed continuously but it was low level stuff until 60mph when it turned into a pneumatic drill. The bike had Starfire forks with a TLS brake front wheel and a pair of recent Girling shocks. Handling was what you'd expect from an old Brit, taut, steady but light; a pleasure to use after my aged Honda Benly but rough roads were a bit spine rattling.
After a week I decided I was going to like the C15, set to work sorting out the best of the chassis bits and electrics. I wanted a classic British look, which meant cleaning up a lot of detail bits, using a teardrop tank and cutting back the cumbersome guards. I finished off the chassis in fern green and black, not a BSA colour but classically British. Once I'd cleaned the gunge off the existing chassis and motor, done a bit of painting and polished up the alloy, the cycle looked jolly neat, even if I say so myself. Apart from some new consumables the cost was minimal as I did all the work myself.
There followed a period when the C15 was afflicted with a myriad of electrical problems, everything from blowing bulbs to flat batteries. There were two causes of all the problems which confused me totally until I got to grips with the subject by reading several large tomes. The first clue was realising that the bulbs were blowing not because of excessive voltages but from vibration. Some new rubber bushes and a bit of old inner-tube solved that one. The charging problem was traced to the Lucas alternator which was partly burnt out, once rewound I was back in business.
My timing was good, the summer had just begun. Ah, I thought, balmy days, country roads and the unique beat of a British single. I wasn't entirely sure about the engine, had been gradually taking the BSA further from home on each ride. It was interesting to watch people’s reactions, varying from incredulity to annoyance, the latter when we blatted through gaps in the traffic whilst some cager fumed in his expensive coffin.
The BSA's clutch turned troublesome when subjected to excessive town riding, gradually seizing up until the lever would not budge. Leaving the bike to cool down for thirty minutes, once the engine had stalled, would free it up but this was hardly the quickest way of getting from A to B and a couple of times I had to take the chain off to push her a short distance home.
On the odd downhill stretches I let the bike rev out in top gear, putting as much as 75mph on the clock, which is pushing things for a C15. As well as the vibes threatening to split the petrol tank and throw the pegs off, there was the open question of the lubrication system keeping up with the valvegear and crankshaft. The odd burst of speed is OK but sustained velocities are limited to around 60mph, which makes the bike a bit of a liability even on fast A-roads let alone motorways. Town and country roads were much more its natural arena.
The brakes and handling were way ahead of that kind of speed. BSA had somehow endowed the dodgy looking tubular frame with better stiffness than most Japanese 250s (at least of the seventies era). The other benefit of the detail work that BSA put into the chassis was wear of consumables that Superdream owners can only dream about. Fuel was a disappointing 70mpg but that was ahead of the vast majority of Japanese 250s.
Of course, the reliability of British engines is way behind the Japanese stuff, even when used mildly. I had lots of fun with the points changing the ignition timing as I rode along and finally they fell apart. I had to stop every five miles to bodge them back together every time they came apart again. I couldn’t call this fun but managed to convince myself that it was character building.
Miles piled up on the BSA over the summer, but sensing the coming winter the top end went so rattly that peds were jumping out of their skins, fearing a runaway dustbin was going to knock them down. The valve guides were loose and wafer thin, the valves were halfway up in the head, one pushrod was bent and the rockers had lost all their hardening. What can you say? Crap design and too much vibration. I'd already bought a spare head, as I knew it was on the way out, which I'd set-up perfectly, everything refurbished and polished until you could see your reflection in it.
The bike didn’t go any faster, didn't vibrate less but there was an unholy silence... for about 250 miles until it started rattling again. That was the least of my worries as the bottom end had started rumbling. Judging by the way the C15 lurched every time I changed gears it was the gearbox falling apart rather than the main bearings on the way out... in my more depressed moments (winter always does that to me) I thought it might be both!
There was nothing for it but to pull the motor out and split the cases. This is where British bikes become a little more complex than the Japanese ones as you can't leave the top end in place. At least all the screws came out with none of the alloy rot horrors of the Japanese engines. My worst fears were confirmed - shot mains, all the gearbox bearings loose with a couple of teeth missing off some of the cogs.
In all, I'd done 6000 miles in eight months of largely pleasurable riding. The chassis was impressive, the engine useful in the way of old British singles and the running costs were no more than a C90. The motor had probably done a huge mileage but even rebuilt ones don't last long. Now, the chassis has a GS125 motor shoehorned in and goes all the better for it. So much for British biking!
Graham Palling