Buyers' Guides

Sunday, 10 January 2021

BSA C15

When the BSA C15 came out in 1958 I wasn't too impressed. To my seventeen year old eyes it had no street credibility. Back then, the fast life was all about big Triumph and Norton twins, not some pudgy 250cc OHV thumper. I didn’t buy one then. No way! But age and time does funny things to a man. In 1990, at the age of 49, I came across a 1959 example that had been restored some five years before.

The owner claimed to have only done 3750 miles in that time. I was mature enough not to quip that the lack of miles was because the machine was so awful. He reckoned that for 2000 notes the machine could be mine. The shark-like smile that accompanied such largesse made me realise that all might not be quite what it seems.


The bike looked OK, although not pristine, and the engine clattered away without any of the telltale knocks, rattles or tapping noises. I refused to spend that kind of dosh on an old relic, however much nostalgia was pulling at my heart-strings. There’s no fool like an old fool - I had no intention of becoming one. We swapped phone numbers.

At the end of 1990 I received a fairly desperate phone call from the owner. He needed the money fast, how much was I willing to pay? £500. There was a pregnant pause in which I swear I could hear his teeth grinding. The deal was done on the proviso I did the 60 miles to his house in York, with the pile of used fifties, that very day.

That was how I came to be riding the BSA home in a snowstorm. One moment there was a weak sun, the next a blinding blizzard. I was snug inside the Belstaffs but the poor old BSA was exposed to maximum abuse. After ten miles the engine ground to a halt in the middle of the countryside. No other soul in sight for miles around no-one stupid enough to come out in that kind of weather.

One of the most curious aspects of the C15 design was that, until the mid sixties, a distributor was fitted. Really strange, considering there was just one cylinder. As this had become covered in a gritty paste, a mixture of oil, dirt and snow, it was the immediate suspect. I should point out that I had no tools, let alone a can of WD40.
All I could do was ruin an handkerchief wiping it clean and quickly popping off the distributor’s cap to let the water out. Three kicks later I was on my way again. It pays to smear the inside lip of the cap with Vaseline to keep the water out.

Six miles down the road a service station came into view. I pulled in, receiving shocked accolades from the owner. He reckoned I was a real hero to be out in those kind of conditions. Two Mars bars and tin of WD40 poorer I was set for the second half of the trip.


Perhaps the most surprising aspect of the old thumper was its relative stability over snow layered roads. Sporting cheap Avons and only a modicum of suspension travel, nevertheless I could progress adequately at speeds between 20 and 40mph. I much preferred shutting the throttle to using the SLS drum brakes over the treacherous conditions. If their sensitivity was better than anything you can buy these days (at low speeds) it would take only a momentarily locked wheel on the icy roads to leave me head-butting the tarmac.

Reaching home, the shivering fit took a while to disappear. The BSA thawed out in the garage, depositing a large puddle of water and oil. The next day it refused to start. I took the distributor apart they were never highly regarded in the fifties, I much preferred magneto equipped bikes. The drive gear was chipped and worn. The ignition timing was before its time - i.e. variable! A refurbished distributor was purchased mail order; I spent two weeks worrying that they might've run off with my money.

Until April I did few miles on the C15. The weather was too nasty and I didn’t trust the motorcycle. I finally ventured out for a sixty mile saunter. Immediately, town riding showed up its age. Clutch drag, the whole bike quaking at the bit whilst at junctions, had both rider and machine overheating. When the C15 overheats the vibes shake the tank and the valve gear rattles away merrily. To make life more interesting, the gearbox liked to lock up in third gear. The selector design was notorious! Someone brought up on modern Japanese bikes would've soon been in tears. I just grinned and bore it.

All was going well, if you can call a maximum velocity of 55mph good (top speed’s 70mph but the vibes make that rather dire), until the front end started to rattle and shake. On smooth roads the C15 handled well and steered precisely. The refurbished suspension was almost as taut as a 450 Ducati. However, the BSA’s tubular frame wasn't up to the standard of the Italian machine. When the road turned bumpy, the front end was shook all over the place.

That wasn't the cause of all the angst at the front end. The disturbance presaged the disintegration of the front mudguard. Before the front wheel jammed up I pulled over. I know a lot of myths, rightly or wrongly, surround old British bikes but the reality was that the commuter bikes were made from the cheapest metals available, often recycled scrap. Unless a great deal of care’s taken when refurbishing cycle parts, rust can form under the shiny surface of the paint. Any weakness in the metal’s quickly amplified by the vibes.

I was able to continue on my trek with what was left of the guard on the pillion. I hoped the police would be understanding and that I didn’t get caught in any bad weather. I should've paid more attention to the engine, only realising that something was amiss by the excess heat streaming off the cylinder. A quick look in the oil tank revealed that it was almost empty. A bolt had fallen out of the engine casing.

This time I had a bag full of tools, bolts, wire, tape, etc. I was able to bodge a smaller screw into the casing and filled up with oil at a service station a mere 200 yards down the road. Sometimes you get lucky. Or not. Five miles from home the screw fell out again. Not being entirely daft, I checked it every mile; no further damage was done.

The loss of oil may have contributed to the agitating knocking/tapping noise that turned up less than 200 miles later. After some investigation with a screwdriver between my ear and the engine I decided that it was either the main bearings or big-end. This era of C15’s had shell rather than roller big-ends, which didn’t like high revs Se engine peaked at 7000rpm but 5000 was more like it) or high mileage. I had to have the crankshaft rebuilt to later, tougher spec.

The top end was OK and I don’t really like mucking around with gearboxes. Of course, being vertically split, the whole engine had to come apart. I have done many rebuilds in my time, the C15 turning out a little finicky but no great hassle. I even succeeded, thanks to modern liquid gaskets, in making the mill oil tight.

The engine ran smoother, would even hold 65mph for a while. Fuel was good at 80 to 100mpg and consumables showed no sign of wear in the next few thousand miles. It was not a machine I felt I could trust, every journey fraught with possible engine termination.


Early ’92 I tried to sell the BSA for a thousand notes. No takers. Around this time the seat disintegrated when the base rusted through. That happened when I was rolling along at 40mph. No fun to have a seat falling apart under you. The resulting wobble almost caused two cars to hit each other head on. The base was much more rust than metal, unlike the front guard which I’d managed to weld. A brand new seat meant for a Triumph twin was fitted.

I rode the bike to a couple of classic events, where I placed a for-sale sign on the saddle. Some interest, but mostly BSA buffs pointing out all the non-standards bits. Someone offered £350 but I had more than twice that invested in the machine. At one event I bought a whole engine for a hundred quid, a later model with coil ignition. Turned over OK but only because there weren't any piston rings in it. I was ripped off!

By the end of 1993 I'd done a grand total of 6000 miles on the bike. Lots of annoying little faults - bolts falling out, brackets cracking up and even the back wheel breaking half its spokes. The nipples had actual worn away their seats and were pulling out. I won't even talk about the electrics.


Early ‘94 I had the choice of doing a complete refurbishment or selling the bike before it stopped working. Rust kept poking out of the paint and chrome, whilst the engine was making some expensive noises. The BSA finally went for £375 and a pile of spares for £150. It wasn’t a total disaster, with a sturdier engine it could’ve survived modern roads. I can’t see myself buying another but can understand why some people might enjoy the experience.


C.B.