IT WAS A DESPERATE BIKE for desperate times, a machine that came into existence largely through the efforts of a handful of very resourceful engineers who pulled a very shrewd rabbit from a very unexpected hat.

If it sounds like a fairy tale, that’s because when this one came off the drawing board there was certainly plenty of fairy dust being sprinkled around Plumstead, south London—the new home of Norton who had vacated their historic Bracebridge Street site in 1962/3.

But this was 1967, the famous Summer of Love year when Procul Harem released “A Whiter Shade of Pale”, when the Beatles gave the world Sergeant Pepper, the year the Torrey Canyon ran aground in the Scilly Isles and Charles De Gaulle once again vetoed Britain’s entry into the EC.

Since 1952, Norton had been owned lock, stock and barrel by Associated Motor Cycles (AMC), a company formed by the Matchless Collier brothers who had acquired AJS in 1931 and later sunk its teeth into Sunbeam, Francis Barnett and James and subsequently found that it had bitten off more than it could financially chew (Sunbeam was sold to BSA in 1943).

Throughout the early 1960s, AMC had been fielding a range of decent enough and largely badge-engineered bikes that, for the most part, satisfied the demands and whims of its solid (or even stolid) boots and Belstaff customer base. Only, that base was shrinking rapidly in the new world order where the motor car was squarely in the ascendancy now that the rationing and privations of post-war Britain were all but forgotten.

In 1966, struggling AMC finally bit the bullet and sold out to Manganese Bronze Holdings (MBH), an ambitious outfit (headed by Dennis Poore) that already owned Villiers and had its corporate fingers in more pies than Little Jack Horner. The result was a new firm called Norton-Villiers that, as part of its restructuring, had very disappointing plans for the other marques in its stable

But if MBH seriously thought it could boost the Norton bank roll, it also knew that it had its work cut out. Norton was then fielding a range of worthy 650cc and 750cc twins built upon an ever-dependable 1947 497cc Bert Hopwood designed Dominator platform; bikes such as the 650SS and the 745cc Atlas (the biggest British parallel twin of its day).

Only, sales were falling and AMC and was rapidly losing ground, cash and prestige with a range that was looking old and stale when compared to, say, the rival offerings from Triumph and BSA. Moreover, Norton’s companion 250cc Jubilee and 350cc Navigator models had failed miserably in the marketplace and had sopped a lot of readies. Something new and exciting was therefore needed—and ideally in time for the 1967 Earls Court Motorcycle Show.

To achieve this small miracle, Norton brought in four hired guns that included Dr Stefan G Bauer (from Rolls Royce), development engineers Bob Trigg (late of Austin) and Bernard Hooper, and John Favill (from Villiers who later worked for Harley-Davidson on the Evo engine).

There was little time to develop a brand new engine (Norton had already been struggling with an earlier double overhead cam twin project known as P10, but had failed to make it sing and dance). The only real option, it was suggested, was to rework the existing 745cc Atlas powerplant—with a reputation for serious vibration.

With respect to Norton’s larger capacity twins at that time, the firm’s chassis orthodoxy began and ended with the Featherbed frame. The Featherbed, after all, had well-served hundreds of race winners around the world and was perhaps the most famous chassis on the planet. Moreover, Norton’s traditional customers simply loved it.

However, Dr Stefan Bauer, mining a rich seam of fundamental engineering principles (as opposed to sitting back on decaying racing laurels), was unhappy with the Featherbed and was quick to point out a number of its failings—not least that it did little to soak up the crippling vibrations pulsing out from every stroke of the Atlas’s crank; vibes that were becoming increasingly problematic as Bert Hopwood’s original 500cc design had been blown out of all practical proportions and had therefore became something of a Frankenstein’s monster.

These vibes, opined Bauer, could however be tamed/minimised with a new chassis; a chassis that would dangle the engine, gearbox and driveline from a single top tube and would control lateral (sideways) movement by a trio of rubber bushes placed at the top, front, and underneath. Torsional (or twisting) stresses would be largely controlled by the top tube itself. The trick was to allow the engine/gearbox/driveline sufficient fore and aft movement, but without allowing it to transmit the bruising vibrations through to the rider.

Exactly how much each member of the team contributed to this new “Isolastic” design isn’t clear. Suffice to say that between these highly talented engineers came the 750cc Norton Commando, claimed by some to be the finest British parallel twin ever, bar none.

The bugbear with this Isolastic system, however, lay in the adjustment. Each rubber bush required careful and precise—and difficult—shimming. If too tight, the engine/gearbox/driveline would lock solid and send the vibes straight into the chassis. If too loose, the lateral movement would become uncontrollable and potentially dangerous.

But what’s with this driveline business, anyway? That’s simple. Merely containing the engine and (pre-unit) gearbox between three rubber mounts would leave these components pulling against the drivechain when under load. That in turn would overstress the rubber bushes creating various action/reaction problems. The solution, therefore, was to mount the swinging arm (and therefore the driveline) directly to the gearbox and suspend that with the three rubber mounts and the shock absorbers.

And it worked. Moreover, isolating the engine from the rider effectively liberated a lot of otherwise inhibiting power. Suddenly that old Atlas engine, now canted forward at a racy angle, became a viable powerplant capable of carrying Norton forward until a modern (i.e. non pushrod) engine could be developed to see off the threat from (primarily) Japan and (secondarily) BMW.

In 1969, production of the Commando at the Norton-Villiers Woolwich factory ceased, and recommenced in Andover, Hampshire with the engines being assembled at Wolverhampton.

After a spectacular entrance, however (with numerous track notches on its belt), things took a sudden downturn with the introduction of the 1972 Combat engine. With its hotter cams, high-compression gas-flowed head and beefed up bottom end, the bike looked good on paper - but considerably less good in the real world after main bearings regularly gave up the fight within mileages as low as 5000.

Not that the basic 750cc Commando, with its racy inclined cylinders didn't have chronic problems that included rapid-wearing camshafts, broken valves, heavy oil consumption, fragile cranks (largely due to incorrect machining), and ignition problems.

But the Combat engine set a new standard of worry, and soon the company was back-pedalling its design and looking for a solution - which arrived largely in the shape of the now famous Superblend bearings designed like tiny barrels (as opposed to rollers) and capable of smoothing out crank-flexing/engine wrecking stresses.

The compression was dropped too along with other revisions that took the Combat engine out of a war zone that was costing sales and damaging the Commando's reputation.

Over the next few years Norton further refined its sugar, notwithstanding a fairly useless electric starter that wound up the owners more than the hardware.

Suspension was improved. Drums brakes turned into disc (disc front in 1971/ disc rear in 1975).

The 750cc bikes went out of production in 1973, and the 850cc model arrived (actually 829cc). For many this bike was smoother and easier to live with, while other Norton diehards prefer the punchier - and arguably more charismatic - 750 machine.

But either bike is a joy to ride and still capable of kicking asphalt in a lot of modern faces, made better by the dozens of mods and upgrades that have carried this bike safely into the 21st century.

In 1975, left-side gear change and dodgy electric starters were introduced on the Mk3 850s.

By 1977 however, with the various domestic and industrial tides lapping on the shore of the British motorcycle industry, the last Commandos were assembled (save for a few special constructions that appeared over the next few years).

Tops speeds of 120-125mph are frequently bandied about for these bikes, but you'll find few owners who'll straight-facedly admit to seeing those kind of speeds. More realistically, the oomph will have petered out at around 110-115mph, except in a rare instances in which some special magic seems to have been breathed on certain bikes.

But these classic Nortons are nothing if not full of character. They should be owned, or at least ridden, by everyone at some time in their lives.

Neil Hudson: an owner's story

“I bought the Norton 4 years ago. It's a 1971 model, and was in a pretty rough state - but basically all there. I stripped every nut and bolt and either changed to stainless or polished fasteners. I took the head and barrels off, decoked it, polished the ports, bought new cycles parts, fitted new exhaust pipes and resprayed the tank, side panels and mudguards using a two-pack pearlescent red.

“The frame is painted with cellulose which, unlike two-pack, needs to be regularly waxed and polished to keep the shine on it. But the black cellulose frame certainly looks better than stove enamel or powder coating.

“The saddle, incidentally, is from Corbin, and the primary chain case has a two-pack finish.

“It’s not my first Norton. I had another some years ago, plus various other bikes: a BSA Barracuda, a C15, and a 650cc Triton.

"But I particularly like this bike. It rides nicely and looks good. It's worth maybe £4000.

“It took a long time to finish, partly because I suffer from rheumatoid arthritis—which I’ve had since I was twenty two. I need to have blood tests every month, and I’m on a pretty gruelling range of medication.

“Also, I’ve got a metal plate in one hand, and my joints ache a lot, especially when getting down on the floor and polishing things. I need a new knee joint too, but I can’t have that sorted out due problems I had some years ago when withdrawal from the medication I was on led to a heart attack.

“I’m okay now, mind, but the condition limits what I can and can’t do. When the pictures of me and the bike were taken at the Ace Café, for instance, that was the furthest I’ve been able to ride it—and only then after stopping constantly to rest. It’s the wind blast that does it, plus my bad hand that gives me problems holding onto the ‘bars.

“I did consider getting a little fairing or something to help out a little, but that would require lowering bars, so I’ll probably just leave it the way it is.

“Actually, since the pictures were taken, I’ve changed the colour. That is to say, I’ve bought new cycle parts and have kept the red parts. The new colour is black. But not any black. It’s a very special pearlescent metal flake in which all the colours, under the right conditions, go into reds, greens and blues. It’s amazingly rich and deep and unlike anything I’ve seen before.”

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