British Iron: BSA Bantam and Ariel Arrow

When I tell people I'm a fan of British motorcycles I get the usual reactions - either total disbelief that anyone could be so stupid or extreme interest, usually with tales of a misspent youth thrown in for free. When I go on to add that my interest is solely in British two strokes, amazement is the predominant reaction. My prime interest out of that large catchment area of disillusion, the BSA Bantam and Ariel Arrow. As with many things in life, such mad passion came about by accident. I knew someone who knew someone who wanted shot of an Arrow and assorted garage full of spares. Who then went on to point me in the direction of a Bantam owner, who was similarly moving on to bigger and better things.

One day my garage had to accommodate a decaying Austin Allegro, the next it was stacked to the rafters with an excess of old stroker parts and two fully working motorcycles. I did the decent thing, sold the car. Spoilt for choice, I decided to explore the abilities of the Bantam first. This started out as a D10, had lots of later engine parts fitted, as well as many non-standard chassis bits, but the owner reckoned it represented the very best of Bantam engineering.

The bike could trace its ancestry back to the D1 of 1948, itself inspired by Iron Curtain strokers before the curtain went down, one of the joys of winning World War 2. The D1 was a mere 125cc, rigid framed, 4.5hp stroker, basically a ride to work hack whatever the classic buffs might tell you. The odd one is still in use by the more desperate learner, though it's likely they have sneaked in the 175cc engine.

In 1954, the D3 emerged with all of 150cc's and 6 horses, though it never really graduated into the modern world. The initial model had an half-hearted attempt at a plunger rear end, which was aptly named in its reaction to less than perfect road surfaces...yes, I've actually ridden an early one and do know what I'm talking about. The paucity of performance was just as well given the abysmal handling and braking, though both were better than the D1. The BSA factory had yet to get over the postwar metal rationing ethos.

Come 1958, the much loved if abused 175cc engine was shoved out of the factory on to a virgin world. This was the D5, but it took a few model years to sort out the engineering and handling problems resulting from having all of 8 horses to hand! By the time the D10 was flowing out of the factory, there was a half decent frame, easily upgradable suspension and all of ten horses with which to attack our pleasant highways.

Alas, by the time the BSA factory woke up to the Japanese threat it was too late. The 1968 D14 had adequate power but needed a much modded engine to survive, enter the D175, which was a well sorted motorcycle but saddled with the earlier bike's bad reputation. Most of the older Bantam engines have, one way or another, been upgraded to D175 spec, which just leaves the chronic wear typical of strokers of this period - a well maintained engine able to do 20-25000 miles before needing a crank rebuild. Of course, an aged example with less than meticulous work can go down in much shorter distances.

You need to find a dedicated owner, with a garage full of back-up spares! Saves loads of money and buying bits and you can be pretty sure that the bike you're purchasing has the best of everything that's available. My Bantam was typical of such devices, feeling well put together and having a nice glut of midrange torque. By modern standards the suspension was totally lacking in any travel; the large wheels and skinny tyres feeling like something off a pushbike. Though thrown around by bumpy roads, the bike held its line and I could feel the tyres reacting against the road surface; none of the excessively remote feel of a modern commuter.

Ride a Bantam, with newish chassis bearings and suspension components, and contrast it with some modern Jap commuter - CG125, GS125, etc - the British stroker feels much tauter, stronger, more securely placed on the road (the difference of especial note in the wet). Which tells you as much about how much the Japanese engineers get away with as how clever were the old British designers, thirty years ago, when constrained by use of fairly minimal components.

The Bantam weighs around 200lbs - leave out a lot of metal and you also leave out a lot of stress. Something modern Triumph designers ought to think about. Power is sufficient to hit 70mph, no more, though there are loads of tuning options which will push the cycle close to 90mph - and a very rapid demise.

With its light mass and tight handling, though, you do get to exploit its power to the maximum and anywhere except licence-kill roads the BSA is actually one hell of a load of fun! This assumes the electrics are in good shape, the spark plug is newish and you know not to bog the motor down at low revs in a tall gear... all things that can add up to a stalled engine. Bearing these restraints in mind, there's no reason why the Bantam can't be flicked through traffic, curving roads and roundabouts as rapidly as any modern, small capacity motorcycle. And in the wet, at a faster rate than most, such is the way it melds delivery of power within the constraints of its safe chassis.

Given that pollution laws weren't a problem back in the sixties, the simple engine design results in good economy - a minor amount of mildness on the throttle bettering 100mpg; rarely does it get worse than 80mpg. One gets the impression that creators of modern bikes just don't give a damn about designing in economy. It was miserly in other ways, the cheap tyres and chains lasting for tens of thousands of miles; its only real digestible, the spark plug, which could die in less than 1000 miles. And oil, of course.

When I bought the bike I thought it was a pretty good deal and haven't really changed my opinion over the past six years and 34000 miles - even if that kind of mileage has resulted in two complete rebuilds and an extra barrel and piston swap. The latter due to some substandard parts I'd fitted - my excuse anyway. The engines are delightfully easy to work on, as long as all the threads and bolts are in good condition. One engine I bought was close to hell, due to bodged bolt heads and seized-in screws.

Many people are addicted to Bantams, and I can see why. The Ariel Arrow also has its adherents, just as strong minded. It's a rather odd mixture, a stroker twin engine in a pressed steel chassis. Considering the primitiveness of the Bantam in 1958, Ariel did a pretty amazing job of producing a modern commuter using the production tools then available.

What emerged was the fully clothed Ariel Leader, a device that offered full weather protection as well as the relatively civilized two cylinder configuration. The British motorcyclist of the day wasn't overwhelmed with enthusiasm for this most unusual looking machine and sales didn't threaten the BSA empire. They haven't aged at all well, their lines only too redolent of the limits of mass production back then - that is, bloody ugly.

The Ariel factory, aware of the difference between their view of the bike - an ultra advanced commuter that rewrites the motorcycling game - and the public's - you've got to be joking - stripped off all the protective plastic, tweaked the motor, and launched the Ariel Arrow on an unsuspecting public. This was the British version of the Yamaha RD250, a decade before the Jap's got their act together. It was still a rather odd looking machine, nowhere near the neat lines of later Bantams, the worst features the massive structures of the front end, mudguard and forks both. Though it couldn't be said that either pressed steel frame or petrol tank had a pleasing line in them. Curiously, after owning the bike for a few months they do meld into a rather cute whole! Most people chortle happily when viewing the Ariel for the first time, figuring it some foreign affectation!

Whereas the Bantam would be easily recognizable as a motorcycle when sat on for the first time, having a comfort that matched the natural elegance of its lines, the Arrow just feels plain strange. Though lowly mounted the rider feels rather lost in space and all the sensations from the suspension are wrong. Seems far too softly sprung and what directional accuracy it possesses comes as something of a surprise. Until you brake and the front forks graunch away without actually moving very much.

The engine's easier to live with, though it lacks the Bantam's off-idle pleasantness, chatters away to itself until a couple of thousand revs later it sorts itself out and gives a punch that no reliable Bantam mill could hope to emulate, despite the chassis carrying an extra hundred pounds of mass.

The Ariel claims 20 horses and when they sing their song they are clearly felt. The Arrow's motor was happy pushing the bike along at 70-75mph, humming away like a bumblebee at the honey. The chassis was an entirely different matter. The pressed steel frame probably has more than adequate strength for the top speed of 80mph, unless you are unfortunate enough to have one that is rusting from the inside out. However, both the swinging arm mount and suspension, at both ends, are hardly up to the task, neither easily upgraded.

Coming out of a bumpy bend under acceleration, the Arrow made me recall those old horror stories of Kawasaki H1's, albeit at somewhat more moderate velocities but with the same feeling of the frame about to disintegrate underneath me. Oddly, despite all the energetic shuffling the bike did actually manage to get through the curve on something approximating to the required line. I became used to these wild oscillations but never felt really happy about them.

If the Arrow's engine was an order of magnitude more powerful than the Bantam's, it was also much less reliable and a finicky little thing to set up correctly. So much so, that I left the servicing to a friend who was into Leaders right from their launch. Despite 250 mile maintenance sessions, I never managed to make an engine last for more than 10,000 miles - sometimes the gearbox or clutch going down, other times the crank's bearings! Bear in mind that I did use it on long, fast runs. My friend's Leader would do more than 20,000 miles when ridden mildly. The Arrow also burnt through the consumables, oil and fuel (45mpg) much more rapidly than the Bantam.

That might make the Bantam the easy winner but I do like the Arrow for its acceleration and curious shape. Mostly, it's hopelessly out of date and out of place on modern roads. Not so the Bantam, the chassis easily up to the mark (with TLS front brake added!), all that's missing is a bit more engine power and I may eventually fit in a modern Jap motor. Maybe!

Dick Williams