Copyright (c) umgweb.com 1998
About five years ago I had a ride on an ex-plod Wankel Norton. It had done something like 120,000 miles and ran like shit. Low rev surges, massive hesitations whenever I wound open the throttle and a weird shriek out of the exhaust that did my head in. I gave it back to the owner with a pitying look and pat on the head.
When I saw a Norton Classic propped outside a house just down the street, I crossed the road to avoid it. But curiosity got the better of me when a for sale sign was placed on its saddle. I could have it for a long weekend of testing if I was willing to let him have my prime CBX550 for the same. This was a low miler, only 9000 miles on the clock.
Ran beautifully. I thought the Honda was smooth, but the Wankel engine redefined the meaning of that word. Acceleration was impressive, I kept running out of gears as the bike screamed up to 9000rpm when the rev-limiter cut in. The gearbox was slick but there was a touch of chain whipping at very low revs. The gearbox locks up when you come to a standstill, needs to be knocked into neutral first. If I forgot that I found a bit of clutch drag whilst waiting at junctions, but nothing that using the front brake doesn't sort.
The aircooled, twin rotor engine does run very hot, despite the huge cooling fins. It needs a bit of motion to keep the temperature down - really needs a fan to force the air through it instead of using the induction air flow, but this is a minor point. An awful lot of clever engineering went into the motor, keeping it both simple, reliable and light. British engineers can do wonders, but a lot of them are removed from the reality of marketing their products - the Wankel was a loser before it began, really.
The styling's as restrained as the chassis engineering, but the latter works well on the road. With all of the bulk of the engine lowly placed, the bike has a centre of gravity that inspires security. It's very safe in the wet despite having a ridiculous 32 inch seat height and wide saddle. Wholly lacking is the feeling of being one with the machine, which was so much a part of British motorcycling in the sixties. An astonishing omission for a bike with Norton on the petrol tank.
Having started with a light engine the chassis further annoys in weighing an incredible 500lbs (though it never feels that heavy). If the Wankel engine had any chance of making it in the world, its lack of vibration should have allowed it to be the main frame member, ending up weighing 250 to 300lbs. This would have transformed the effect of the available 80 horses on the acceleration, although to be fair, the bike performs better than any British twin of the sixties or seventies.
Top speed turned out to be 130mph on the clock. The engine didn't seem to have run out of power, if the rev-limiter was disabled it could probably have kept going and going until the whole thing exploded. The Classic can be considered as either a 600 or 1200, depending on how the rotors are measured, and according to which way it's rated it turns out to be good or mediocre.
The bike had a way with it. It seemed to float across the countryside with a total relentlessness and, once I'd adjusted to the riding position, in good comfort. Fuel averaged out at 45mpg, which included a bit of speed testing and cruising at 90 to 100mph for many hours. The owner reckoned he could achieve 60mpg under mild riding. The engine uses an oil injection system which blew the lube at around 300 miles per pint. You have to use special Wankel oil, not whatever comes to hand, unless you revel in mechanical disasters.
The one area that I didn't like was the braking. Triple discs that reacted to water by refusing to work for a worrying couple of seconds, then tried to skid the tyres off the road. One good thing about wet weather riding was that Norton had fitted decent mudguards which kept most of the muck off the machine and rider. Typical of bikes made in merry old England (new Triumphs aside!).
Apart from being a bit slow turning in town traffic, the Classic took everything that I could throw at it. Top speed could easily be used as a cruising speed - if you had massive arm muscles - the bike feeling rock solid on smooth motorways. It could be a bit finicky on very bumpy roads, but the twitchiness never developed into a strong weave or wobble. Country roads were taken with ease, as good as the much lighter CBX but with more violent acceleration.
When I came back to the Honda I thought that the engine was about to explode. After the smooth, sophistication of the Norton, the four cylinder CBX felt rough and vibratory with a horrible gearchange, like some old abortion of a British thumper. It took at least a week before the noise and vibration faded into the background again. You never know real joy until you've experienced it for the first time.
The Classic made me feel full of despair rather than joy one time. In the middle of the Cotswolds the engine suddenly switched itself off. Dead motor, we freewheeled to a halt in the middle of the countryside. Wonderful scenery but not so great if you have to push a great big motorcycle for miles. I was beginning to curse myself for a fool. The motor seemed locked up solid, refusing to go into neutral or even move. All I could do was wait for it to cool down, leap up and down on the seat to get the gearchange to bounce down to neutral. I was much relieved when it came back to life, even more so when the rattling clutch quietened down. The major downside of Wankel ownership's that you never know when the rotor seals are going to go down.
Despite some misgivings I was quite keen to swap the bike for the Honda. I was even willing to top the deal up with a few hundred quid. I agreed that the CBX was worth a grand, but was totally gobsmacked when the Norton's owner reckoned his Classic was worth five thousand notes.
I could buy a very nice CBR600 for that kind of dosh, or a new 600 Bandit plus lots of change. No way the Norton represents good value, but its relative rareness and the fact that it's British, means they fetch that, and even more, on the market. So I didn't buy this one but can recommend them if you're willing to spend the dosh. They add a whole new angle to the motorcycle experience.
Clive Knight
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Oh for a good British motorcycle, thought I once in a blue moon. I'd been there, done that...on Triumphs, BSA's and Nortons. Gone on to a series of fearsomely fast Japanese fours. But, yet, I still found myself occasionally lusting after some British relic. The UMG reckoned a lot were renovated, revitalized and re-engineered, to quote an unusual amount of enthusiasm. Could it be true, or was it just another media ploy to sell copies? I had to find out.
The classic glossies provided an excess of dealers for me to visit and even some private ad's for me to follow up. I even cajoled some tests rides. A Triumph 750 was a rolling massage table, a BSA Spitfire shed parts at an incredible rate and by the time I tried a Norton 850 I was ready to be amazed by its Isolastic absorbed lack of vibration. Hey, I'll have one of these. Not unless you've got five grand to burn, said the dealer.
Apart from the lack of vibes, I was well taken with the surly torque and stable handling. The bike had the vernier shim conversion which made setting up the Isolastics, so that they both absorbed vibes and held the bike together, relatively easy (as the swinging arm was only connected to the frame via the Isolastic mounts...). Oh, yes, it also looked perfect in its classic shape. I had to have one.
The only cheap ones were in a disgusting state. By cheap I mean under 2000 notes. I persevered, being somewhat annoyed with the amount of lies people told over the phone. Eventually, for £3500 I found a 67000 miler, slightly shabby chassis (but with the vernier shims) and a rebuilt engine. I knew it was a good one from the way it came to life first kick, powered us up to 120mph at a rate that would shame many a Jap four, and from the lack of vibes or oil leaks. The owner had kept the bike for ten years, was only selling because the wife had dropped her fifth brat and a Transit van beckoned.
I figured I could do a respray myself and soon have it shining with all the glory of a true Brit. The bike was basically a Mk.3 but with the odd chassis bit off earlier models. Definitely not concours, more your well lived in, cleverly updated and generally sorted piece of tackle. I sprayed her silver grey, polished the alloy, filled the tank, primary drive and gearbox with fresh oil, then headed for the open road.
Around Lancaster way there are plenty of fast back roads, which were taken with aplomb by the charging, snorting Commando. Though in its lack of vibration it was relatively civilised it was still a beast at heart, a raw and raunchy 850cc vertical twin. Masses of torque thrust the relatively light and narrow chassis forwards in a most rewarding and exhilarating manner.
It's also one of the few British twins that will reliably canter along at 90 to 100mph, without a deluge of vibration and the old bits falling off routine. In its day, the engine had a reputation for blowing up in a big way when tuned or hard used, but using the later engine parts lovingly assembled removed most of the horrors inherent in an engine that could trace its roots back to a mild old 500cc twin.
So impressive was its general performance and usability that a few Jap replica riders were won over by its brutality. It couldn't do 160mph but it could get up to 120mph in a relentless and charming way that held the unwary and innocent rider all agog. Wonder was even expressed that the British bike industry went so easily down the toilet. Two friends ended up trading in for Commando's.
This unlikely trio was given pause for thought when one of their number (unfortunately, this writer) suddenly found his machine rattling furiously around the top end and smoking away like a 30 year old MZ 150. Surprise was expressed that it didn't have a camchain tensioner as it sounded just like a CB750F1, I once owned, at death's door.
The noise was coming from a loose exhaust valve guide that was merrily popping up and down in the head. Having removed the cylinder head it seemed like the decent thing to do - to gas-flow it, upgrade the valves and their seats so unleaded could be used as well as adding new valve guides. I did most of the work myself, total cost coming out at £120. The bores and pistons looked just fine, were left well alone.
Unfortunately, the engine pinked disarmingly on unleaded due to the high compression pistons fitted, so the new valves were a complete waste of dosh. Valve guides are something of a weak spot in Commando top ends, can go without much warning. With the gas-flowed head, economy improved from 45 to 50mpg, although performance didn't increase to any discernible degree - no doubt the poor aerodynamics of a naked machine overwhelming any small amount of extra power that might turn up.
One of my mates engine's blew up in a big way, as in the con-rod poking out of the crankcase. Turned out he was regularly revelling in taking the engine to nine grand! This is a quick way to reduce a Commando engine to a molten mess however much it has been upgraded or re-engineered. He was led away in tears after this had gently been explained to him. As noted, these machines do indeed get to you.
My motor ran for another 14000 miles, or so, before performance went awry and starting became awkward - not something you want to experience on an engine that needs a real manly kick. I was tempted to blame the electronic ignition, always on the lookout for an easy escape, but, no, a local expert in these matters reckoned on worn out bores. Quite literally as they were already on maximum oversize. A few phone calls to a couple of Norton spares dealers secured replacements plus brand new pistons and rings.
Even after such a low mileage both the valves and the guides were also showing signs of serious wear, so another round of replacements. The crankshaft felt secure on its Superblend bearings but the primary chain and clutch were both well knackered. When it was all sorted out, I'd spent over £450!
Meanwhile, my other Commando riding friend had sold his machine at a nice profit, having done 21000 miles with nothing more irritating than regular 500 mile services. But he could tell which way the wind was blowing, realised it was only a matter of time before something nasty went down.
I suppose it depends on how seriously you want to take things. If you're just after the odd Sunday afternoon outing, the bike will probably last for years but if you're into heavy riding at reasonable speeds then it can be very quick wearing. Money's saved on the consumables - I found it very hard to wear out a set of Avons or the cheap and cheerful drive chain, whilst the rather primitive front disc made up for its basic nature by never coming close to wearing out the pads in 18,000 miles - but that included some hairy moments in the wet.
Not that any of this will stop the true enthusiasts singing loudly their praises because they have a certain character coupled with a great deal of practicality that makes them rather unique in the old British bike game.
A.M.R.
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A brief faltering in forward motion led me to halt and park the bike, a bored out 920cc Mk2A Norton Commando. Erratic reliability is not uncommon with British vertical twins, I thought to myself. My angst on this occasion was unfounded because smeared around the rear wheel rim were deposits of German Salami. Said item had fallen out of the various packages adorning the rear of the bike which could only loosely be described as luggage equipment.
Huge panniers and excess weight at the rear do upset handling and if you want a really exciting time, fit a handlebar screen as per the Highway Patrol. The only other time handling was truly thrilling was due to 6lb tyre pressure in the front. I have fitted an Interpol type fairing and things are generally okay with this. Handling is fine with loads of ground clearance with only slight vagueness from the front end on long sweeping bends at high speeds. Whilst not in the Featherbed class, it does track around bends well - usually, I find that I lean more than is needed.
Early UJMs are nicely gobbled up in any swervery, the last being an XS1100. The state of the art race reptiles are another matter and put me in the moped class! There is much debate amongst owners on handling and Commandos do seem to vary a lot.....my engine is not shimmed especially tightly in the Isolastic mounts, the tyres are ribbed Roadrunner at the front and the standard one at the rear - I've never come close to a tank slapper.
Strange, that the bike can keep going so well in the wet, when riders of more modern bikes are backing off the throttle and fretting away not sure when the tyres are about to let loose. Most British twins are like that, designed to be ridden in all weathers (tested as they were in merry old England rather than arid Japan), the combination of torque inspired power and surefooted roadholding meant the rider was usually aware of what was happening between tyre and road. It would be interesting to see how well the latest tackle went on old fashioned tyres.....worth trying if you have a death wish.
If only the hassle free handling was matched by the engine! This is definitely not a fit and forget component, the latest little foibles being a broken timing chain and a blown head gasket. To be fair, these malfunctions can be attributed to an engine rebuild by a cowboy. Split link timing chains should not be fitted to Commando engines and the gasket should not be copper (fit composite ones). No problems since.
The Commando engine had an initial reputation for rapid self destruction that was only cured when specially made Superblend bearings were designed for the crankshaft - there can be few bikes left that have not been converted by now. The other problem was a weak contact breaker and advance/retard mechanism that used to vary the timing in an amusing manner - electronic ignition solves this one.
So why was I slicing Salami on the Kent coast at 7am on a wet October morning? Well, I'd just rolled off a trans channel special after a trip to Germany. You might consider this to represent boundless optimism combined with stupidity. Certainly, the German lorry driver I shared a layby with somewhere in the Ardennes would have agreed.
He watched as I attacked the exhaust pipe lock-ring with a brick - a well known Commando vice, loose exhaust nut clamp rings. Usually, a special C spanner does the business but the threads in the head were dodgy, something to watch when buying. Otherwise, regular checks with said spanner are in order. Cracked exhaust pipes, especially those with balance pipes and/or not made from the stronger original steel, are quite common. Stainless steel items are not a bad if expensive idea.
Anyhow, having demonstrated the superiority of British engineering, I continued with a memorable ride along the sweeping bends through hilly woodlands at a steady 80-90mph on nearly deserted roads. With the rev counter showing 4500-5000rpm, the engine felt bullet-proof, but this, of course, was a grand delusion produced by the lack of vibes and the sublime confidence of its exhaust note. The euphoria ended somewhere in Northern France with a stall at the traffic lights and a subsequent refusal to restart. RIP killswitch, which after disconnection allowed further progress to Calais. The latter stages were covered in the wet at night in company with a crazy Renault 5 driver. Honour was satisfied, but only just.
This highlights the passage of time. When the bike was built it could happily burn off Avengers and Cortinas, but these days it has problems with modern cars on motorways. True, even now, it will stomp away from most vehicles up to 90mph, but then it all quietens down, with the bike struggling past 100mph. Prone on the tank restores some speed but it makes you look like a right prat.
Rubber engine mounts take out most of the vibration. It is, after all, an old design routed in the fifties with two huge pistons moving up and down together with no silly balance shafts. What is left is various strange sounds, shakes and rattles sub 2000rpm....I feel it is an acceptable price to pay for the relative smoothness of what is an archaic British vertical twin. A 21 gearbox sprocket (bigger strains the gearbox) gives a cruising speed of 80mph at 4500rpm with some reliability. Sustained adventures beyond this and, say, 6000rpm, through the gears guarantees a super quick wear out rate!
So my 1200 mile trip to Germany was not without incident but the bike was good fun and it's something a little bit different (though, 50,000 were made). The haul up the M1 at night to the Midlands was a real drag, something not helped by the alternator deciding to fade away, with the charge light only going out above 4000rpm. Eventually, I only reached home on the pilot light with the engine popping and banging away. Main beam was a good killswitch. A new rotor and stator cured that problem, but you have to pay attention to the gap between these items. The later, welded type, is rather more reliable than earlier alternators.
Mechanical competence is not a strength of mine but fortunately help is at hand. The spares situation is excellent with many parts better than the original ones and the bike is generally easy to work on (though, someone who tries to put the cylinder head back on for the first time might not agree; those pushrods). Most components, such as the electrics and gearbox, can be uprated and beefed up, as well as harder camshafts and various improved bits. At a price, they are no longer in the cheap and cheerful bracket, something which goes for the purchase price as well. There is also loads of literature, service notes and an owner's club. If you're over 25 you get excellent insurance value through the VMCC.
To be honest, the bike is a bit of a black hole given the money spent on it, with most major components having been renewed. As stated, this is the result of thrashing it. Treat it as a gentle tourer with perhaps the occasional thrash and active life is prolonged with much less cash. The amount of money and time I'm willing to expend on the bike says a lot about the rewards of its riding experience - oh yes, a days ride on a Commando leaves you with a lot to think about.
To finish off, here is some data. Top speed around 100mph (sitting up), 55-60mpg with an SU carb, 48mpg with a single Amal and under forty with twin Amals. O-60mph in around five seconds on a good day. Front tyres last around 20,000 miles, rears 7000 miles, chains about 8000 miles and primary chains 30,000 miles. Boyer ignition is excellent and trouble free, save for a loose wire on the back of its mounting plate. The crankshaft assembly is original at 50,000 miles but Superblend bearings were renewed along with the camshaft and gearbox layshaft bearing at 41000 miles. And just like the Japs, it needs an oil change every 1000 miles. You see, you've got to work at it.
Michael Jansen
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I have owned, ridden and played with many a motorcycle in the last twenty years. The only one that has stayed the course all that time is a 1971 Dunstall 750 Commando. I bought the bike in 1975 with just 4000 miles done. Cynics might suggest that such a paucity of mileage was caused by the Commando engine's liking for self destruction, early examples being reduced to mechanical wreckage well before the warranty expired. But they would be wrong, at least in this particular case.
The motor had been carefully rebuilt by the Dunstall crew, fitted with mild cams, low compression pistons and a single carb. The one owner was aged and obviously had trouble draping himself over the large tank on to low clip-ons. Commandos, at that time, had received lots of accolades from the press and only had to deal with wimpy Honda 750 fours and insane Kawasaki triples. I had just tired of a Honda CB500 four, which although civilised was bland to the point of boredom.
Which certainly couldn't be said of the Norton, it had all the character of a particularly crazed baboon, leaping about at tickover like the engine was about to pop out of the frame, whilst chattering along at 5000 revs could in no way be called relaxed. The Commando was part of a brash, brave new world where the maximum amount of enjoyment had to be extracted for the least amount of effort.
That may seem a wild thing to say about a big Norton twin, but the 750 was in such a mild state of tune that it could be bunged in fourth and rolled off from anything but a standing start on the throttle. Not that the angle of the clip-ons nor the heaviness of the clutch encouraged you to play around with the heavy, slow gearchange. The trick was to lurch the brute into fourth at the earliest moment and let the torque slog it out against the 400lbs of steel and alloy. Riding most other bikes after the Norton, was like being forced to have sex with a condom after enjoying the real thing.
In those happy days, with loads of money coming in and nothing much more than motorcycles to spend it on, I usually had a couple of machines in the garage. Which will explain how the Dunstall did less than 30,000 miles in the next ten years. Apart from regular valve checks and oil changes every 2000 miles (the bike had electronic ignition) in that time I did not even have to tighten down the head bolts. Starting off with an engine that was put together properly and in a reasonable state of tune obviously helped longevity.
The Isolastic mounts did a lot to help damp out the ferocious vibes that a British twin of this capacity would normally produce. The Norton was never actually as smooth as a similar capacity four, but most of the destructive effects of the vibration were successfully absorbed by the mounting system. Any engineer, except those working for Norton, would have isolated the engine rather both the engine and the separate gearbox. Given that you have one of the few pre-unit engines still in existence it would have been the obvious thing to do. Norton, however, decided the whole unit had to be isolated, leading to an arcane shimming system at the swinging arm.
This piece of engineering malpractice needs attention every 1000 miles or so and leads to the owner going bald, kicking the shit out of stray cats and becoming generally anti-social. Failure to attend to the shims, or, worse still, getting the clearance wrong, leads to either excessive vibration or a chassis that weaves and wanders all over the road like a decrepit dhow in heavy waters.
Handling is generally par for the course for a British twin when the shims are set up properly. The Norton doesn't change line as fast as a Bonnie, but weaves less in rapid curves and has a bit more suspension movement, which helps over modern, rutted road surfaces. The Dunstall comes with twin front discs that are harsh enough to twitch the forks and cause a few moments of concern on wet roads when their hesitancy is often quickly translated into a locked up front wheel.
The age of the machine is revealed by the way the calipers are mounted in front rather than behind the fork legs. The Dunstall's seat is a gratuitous piece of violence on the rider, going hard after as little as 25 miles. Placing a heavy pillion on the back had the seat buckling all over the place, the GRP base finally deciding it'd had enough, snapping off and throwing the poor old passenger off the back. The way he was jerking around with all the elan of an ace kendo artist indicated that something was seriously wrong; he didn't fall off until I'd got the speed down to 25mph!
I carefully picked up what was left of the seat before I went to his aid. I had to phone a friend to come to collect him, he so dazed that he was wandering around in circles muttering something about it being time for tea. Poor chap, refused thereafter to go near anything with two wheels. The seat was repaired with a bit of steel plate for strengthening and a GRP kit. As the unit contained the rear light and a useful space in its hump, it would not have been so easy to replace. I did add some foam to the seat but it was basically too poorly shaped to help cushion one's weight.
Also, so high that it left me perched atop the bike looking rather ridiculous, whilst the big tank spread legs in a way that only some decadent young lady would enjoy. I usually had other bikes that would serve as long distance cruisers, so it was no great loss. I usually enjoyed myself immensely carving through country roads on the Norton.
The Commando is one motorcycle that could never be called epicene, its character more macho than the most egotistical of Essex men. Even painted azure blue by the past owner, it was not the kind of motorcycle you could easily dismiss, the cement mixer exhaust note made damn sure of that. Even in its mild state of tune it would still put 120mph on the clock, doubtless aided in that feat by pulling very tall gearing and having a svelte half fairing that allowed the rider to crouch out of the wind.
Any wimp who got close to the Dunstall would soon be put off the idea of ownership by the amount of effort needed to fire up the motor. Even with electronic ignition and mild compression ratio it steadfastly refused to come to life on anything less than three gut churning kicks. Sometimes it took as many as ten kicks and you always had to be a licentiate in the language of gentle encouragement. Any belief you might have in this kind of heavy metal being a living, breathing creature was confirmed by its need for endearments every time you went near the kickstart. Swearing or cursing at the Commando would result in one solidly dead motor.
I soon grew used to the mechanical patios needed to keep the machine going. If neglected on a run, it would stutter, threaten to stall on you, until some words of encouragement worked their magic. Call me mad if you must, all I can say is that it worked for most of the time. The Norton grew most distressed when subjected to the usual deluge of water. In the early days it would often grind to a halt, sit there sulking whilst I swore my head off and threatened it with the largest spanner my toolroll held. I knew it was a narcissistic brute that would not at all like having its shiny surface dented. Actually, all it really wanted was some decent HT caps, relocated coils and the occasional dose of WD40.
In 1984 and 1985 I was deeply involved in an affair with a cafe racer Z1 which had a turbo charger bolted on. The frame had been much strengthened and the boost from the turbo was even more exhilarating than the low speed torque of the Norton. Consequently, the Dunstall was rather neglected for these two years, its once shiny alloy oxidizing in protest to a degree that would shame a 20 year old Honda. It indubitable character had responded by refusing to start unless the motor was kicked over at least 30 times - I usually gave up after five and caressed the Z1 into life on the button instead.
When the Kawasaki finally blew its innards every which way I had to reluctantly convince the Commando that it was once again the centre of my attention. It didn't respond until I'd cleaned up all the alloy, given it a new coat of paint and fitted a set of spark plugs. Although it started okay after that, a bout of punctures had me cursing and swearing again.
With nearly 35000 miles done, I was trundling along in town in second gear when some jerk in a Volvo slammed on his brakes. As the road was clear the only possible reason he could have for such an insane act was to make me fall off. I braked harshly then threw the bike around his hideous auto, letting loose with the throttle. If nothing else, the exhaust noise would blow his eardrums away!
With a large grin on my face, I held the throttle wide open in second. With the rev counter flirting with 8000 revs a tremor ran through the machine with such intensity that I backed off instantly and fingered the clutch lever. The bike still ran but it sounded really sick, so I gingerly rode the two miles home, looking out for a Volvo to kick. I whipped the valve covers off but couldn't see anything obvious. Off with the head for the first time. Bent exhaust valves, ruined valve guides and a cracked piston. Could be worse, I consoled myself.
Unfortunately, it was. Took off the cylinder to find that the small ends were gone, the pistons were scored and the bore worn heavily at the bottom. Then I noticed that the con-rods were a bit loose on the crankshaft and that, er, the crankshaft itself rattled about on its main bearings. Bloody hell! I knew the bike was down on power a bit, that it had rattled and knocked somewhat more than I would have liked, but I would not have guessed that the engine was so worn out from the way it had been running.
That night I had to be physically restrained from going around the town battering Volvo cars to death. This was the one time in my life when I didn't have a running machine in the garage. I'd sold what little was left of the Z1 off for a pittance and had been laid off at work. Norton parts were readily available new but I would have to spend a few hundred quid to put my machine to rights. The small ads in Classic Bike turned up a good crankshaft, con-rods and pistons, so I only had to pay out for new valves, guides and a rebore.
Nothing is straightforward, though, I managed to get the valve timing way out and was lucky not to have ruined the new valves. The engine didn't actually start, so I was able to save the day. Old Brits have to be carefully run in when rebuilt, so a gentle saunter up the Welsh coast seemed ideal. As it was high summer the roads were chockablock with caravans; I don't know who felt most disgruntled at our slow pace, myself or the Norton. I had to lope along in second with just a hint of throttle for most of the time, which meant the engine shook in its Isolastic mounts like a pneumatic drill.
I was overcome with neuritis after the first day. When someone tapped me on the shoulder from behind I jumped about a yard and I was shaking like someone in the throes of an epileptic fit for the rest of the night. For some reason, this recreated engine, even when thoroughly run in, never achieved the levels of smoothness of the older bike - perhaps the Dunstall had its original crankshaft dynamically balanced.
For the next two years the Commando was my sole machine, doing 18000 miles in that time. Riding more than a 100 miles in a day was certainly no picnic. The hard seat, harsh vibration and crippling riding position combined to make me lumber around like a woman about to have a miscarriage. The suspension had also started to flop about, so I'd bunged on some really harsh Girling shocks that were trying to live out the rest of their life in a quiet corner of my garage and put about a pounds worth of steel washers in the front forks. I was thrown about like a jockey doing the jumps on a particularly violent horse.
A new job meant a fast commute across town was necessary, something the Norton objected to as the gearbox was playing up and the clutch had become so stiff I needed to keep on a course of steroids to cope with it. A test ride on a GS125 revealed a whole new world of smoothness, civility and pavement hopping, so I borrowed the bread from an ever compliant bank manager, this before the feud broke out between banks and their customers. The Norton was sidelined to the back of the garage during the week, only seeing the light of day on sunny weekends.
It objected to such ignorant behaviour by burning the whole electrical system to a frazzle. The battery usually only lasted for a year, anyway, and was due for replacement. The alternator was a charred mess, as was the Zener Diode, rectifier and large capacitor. The wiring had melted to an extent that made me lucky the bike had not been consumed by fire. All this happened sixty miles from home. I had to push the bike two miles to a farm, convince them I wasn't an Hells Angel about to rape and pillage the place, leave the bike there whilst I hiked and bussed back home to convince a mate that it was his duty to take his rat Bedford van on a perilous journey to collect the Norton. He broke down on the way back, but was in the AA, so the mechanical duo were safely carted back to our town.
The Norton was left to languish for nearly a year. I even took the GS on some longs runs, quite amazed at the way it coped with such distances in a comfortable, quiet way. But I could not quite bring myself to sell the Norton, I had too much of a sentimental attachment to this machine even to be moved by the large amounts of dosh they were beginning to fetch. I slowly picked up the necessary electrical bits over the months and eventually rewired the bike.
That was three years ago, the bike now has just over 62000 miles on the clock and is still running okay. It's had a new exhaust system, petrol tank, some better suspension and the rear wheel respoked as it started breaking up. It won't do better than 50mpg or 105mph, these days, although that lovely wide burst of torque is still there for the taking. I took the gearbox apart to find some teeth missing off the cogs which were replaced with good used ones. A new, nylon lined, clutch cable has lowered the amount of hand muscle required.
I also reluctantly ditched the fairing and put on some more comfortable bars that don't threaten to wreck my back or kill my wrists off. With a better seat the machine would just about make it as a useable tourer, but the way the engine rumbles past 70mph in top means it's really no faster than the little GS125! To be honest, the machine is way past its prime and probably due for another major rebuild before it gets to 65000 miles. It says a lot about the sheer character of the beast that I've already got all the bits waiting for the moment of decline!
Dave Crutchly
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In the sixties Norton, Triumph and BSA were all deadly enemies, each with their own virtues and devotees. Norton had the best chassis, Triumph the superior engines and BSA were somewhere between the two. Perhaps typical of British engineering at the time, when they were flying high on an excess of sales and lack of big Japanese rivals, there seemed little point in investing in new machines. And when things began to fall apart, there was sod all money to renew the ancient machine tools and invest in decent designs. First BSA merged with Triumph, then there was Norton Villiers Triumph and in the end just poor old Meriden knocking out 750cc vertical twins.
Along the way there were attempts at modern bikes. The Trident wasn't really any worse than the Honda CB750, save that it lacked an electric start and front disc brake.....and sometimes had dodgy valves and poor build quality. A well put together T150 or T160 is still an interesting motorcycle that can be very useful, unless, of course, you've ridden a new 900cc Trident. With the new Triumphs doing well, making the old triple seem obsolete most of the attention, nay devotion, has turned to the old OHV twins (especially now that it looks like Triumph won't be building new Bonnies).
My own Bonnie is a sensibly modded 1972 job, one of the last drum braked 650cc models but with the then new frame with the oil in the upper tube. It shares garage space with a Norton 750cc Commando of the same era, an Interstate model with Superblend bearings and electronic ignition. Both machines run stock but renovated chassis and are still used as often as ever.
The history of the 750cc Commando's engine goes back to their 500cc unit. In the late sixties Norton found themselves with the Atlas, whose 750cc's produced such a terrible flurry of vibration that it was almost unusable. This may have had something to do with using the same crankshaft as the 650 Dominator, the big capacity route being the cheapest way of upgrading British bikes to compete with the Japanese - in fact, the process so stressed their engines that they lost most of their ruggedness and charm.
Anyway, faced with a market that demanded speed above all else and an engine that tried to shake itself out of the frame, the now infamous Isolastic mounts were born. The engine still shook, to the extent of often destroying its points, but most of those vibes were absorbed by the engine mounts. The famous Featherbed frame was junked in favour of a new tubular trellis to match the engine mounts. As the whole engine was isolated it meant the swinging arm was not mounted directly on the frame! The handling depends entirely on how well the Isolastics are set up.
Just as the Norton really needed a new engine design but got, instead, a new chassis, so the Bonnie was supplied with a new frame when the old one had evolved quite nicely over the decades from a speed wobbler into a relatively stable device. The Triumph frame was supposed to be common to the BSA twins, although in reality Triumph had insisted on retaining their swinging arm mounts between frame rails and back of engine, so even the savings from common running gear couldn't have been that high. The one downside of this chassis was a tall seat height that left the rider perched high on the bike - a most un-British like trait!
The Bonnie makes up for this with a gutsy engine. 50 horses at 7000rpm is nothing to write home about, but these are real British horses rather than the effete Japanese ones, with a direct connection between the throttle action and the way the bike accelerates. With 400lbs of mass, many a modern Jap has been surprised by the way it'll accelerate up to 80mph, although top speed is only 110mph.
Where the Triumph thrives on revs (at least up to 7500rpm) and revels in being used hard through its gearbox, the Norton is more refined, slightly more restrained, partly because it's fitted with taller gearing than originally supplied by the factory and partly as a result of its extremely long stroke (89mm). Where the Norton really shines is sticking it into fourth gear at 50mph and opening the throttle. A tremendous shove in the back comes streaming in as its torque flows in relentlessly until 6000 revs. Even the factory advised against going above 7000rpm and even though the engine is claimed to produce 65 horses at 6500rpm, I limit myself to 6000 revs absolute maximum. With the taller gearing this gives a top whack of 115mph and a cruising speed, supremely relaxed, of 85 to 90mph.
It's possible to cruise the Bonnie at a similar speed but the engine feels very lively, with some quite strong vibration blitzing the chassis. For long life 75 to 80mph is much more sensible. Both bikes have plenty of power in hand for further, brief bursts of acceleration, so can just about deal with the motorway hustle.
If I have to do long distance work I usually take the Norton. It's much more relaxed and has a huge five gallon petrol tank (I would not advise anyone to ride far with the GRP version....). One of the best mods I made to the Commando was fitting a single SU carb, an expensive conversion new but I bought a secondhand one for £75. Smoother running, no carb balancing and better economy.
An original bike with points ignition and twin carbs returned 40 to 50mpg. Just fitting electronic ignition gained 5mpg, probably because the stock points varied the timing so much the engine never had a chance to run as it was designed. It was also nice to have the engine come to life first go, as a hell of a hefty kick is needed. With the taller gearing I was getting close to 60mpg. The SU carb improved that to nearly 70mpg! As I limited revs to 6000rpm there was no real loss of power.
The Bonnie was rather surprising with regards to fuel. Ridden gently it would turn in 75mpg, most of the time around 65mpg was available. Thrashed it would go down to 50mpg but riding like that I was more worried about the engine blowing up than the way the fuel was going west. The twin Amal carbs didn't need much attention so I had no real inclination to turn the engine into milder Tiger spec.
The Bonnie was brilliant on both country and A-roads, or anywhere with lots of curves. The sidestand prong has to be cut off, otherwise it'll dig in and try to throw the bike off the road. Vertical twins have always had the edge over triples and fours because their engines are narrow and can be thus mounted low, and the Bonnie is deliberately set up for highway kicks. Although the Norton only has an extra inch in wheelbase over the Triumph's 56 inches, it feels much more lazy, much better suited to the faster A-road and motorway curves. It feels slightly less natural than the Triumph, but with the Isolastic mounts firmed up is more stable, less affected by road bumps or white lines.... both machines were shod with Avons on 19 inch wheels, tyres lasting a couple of thousand miles longer on the Triumph, but as even the Norton does over 12500 miles it's hardly a great load on the wallet.
Wheel bearings were crap on the Triumph, though. It came to me as a five year old with only 6000 miles on the clock but took only another 1000 miles to have the back wheel bearings rumbling. I had a look at the front at the same time, ended up replacing them as well, there being a distinct lack of grease. There seemed little point trying to buy bearings from a Triumph dealer, given their poor history, so I was quite pleased to buy a pre-greased set that were sealed on both sides. I haven't had any trouble since.
I also had the back wheel break up. I was two-up with an overweight wife on the back (ouch....) and a ton of camping gear in top-box, panniers and tank-bag but having half a dozen spokes go ping simultaneously in the middle of the Scottish highlands had me cursing the Bonnie and then walking five miles to a phone box to summon the AA. By the time I got back the guy had turned up and was tying down the bike on the trailer whilst the wife mouthed off about my total ineptitude.
I usually took the Norton touring as I never had any qualms about the robustness of its chassis but it had inconveniently decided it wanted a valve job, something it did every 10,000 miles or so. Mostly down to the poor design of valve guide wearing out quickly and letting the valves wobble about. There was some warning of this, with banging in the still original silencers and a haze of pollution on the overrun. Valves needed a 500 mile adjustment even when they were in good fettle.
Amusingly (from a distance) the vibes from both engines destroyed the exhausts but in different ways. The Norton's downpipes would actually crack up although the silencers survived intact. The Triumph would crack up the brackets between downpipes and frame whilst also cracking up the silencers, although as they were of the quick rot variety it might have been a combination of rust and vibration. The Norton caught me out miles from home but I effected a repair with jubilee clips and a couple of cut up tins. Inelegant but it lasted the 220 miles back to my house. The ultimate solution is ultra thick stainless steel downpipes!
Both engines needed regular bolt tightening sessions unless you want to amuse the general populace with a loose cylinder or oil gushing out of the cylinder head. Triumph's valve covers are notorious for twirling off but drilling and wiring them together stops that (until the wire breaks) and the Commando's chaincase is renown for spewing out oil.
The Norton engine had retained its pre-unit construction whist the Triumph had combined engine and gearbox in one unit in the early sixties. There's no real disadvantage in having a separate gearbox. Neither bike has had any gearbox troubles but the ease of removal of the Norton's would obviously be a plus point if, or when, attention is needed. The good thing with a four speeder is that the gears are large and thus long lasting, and in both cases the oil is kept separate from the main engine supply, allowing it to be suitably thick. Missed changes were never a problem on either bike. The Triumph's change was a touch faster, matching its harder revving engine, but the Norton's had a cleaner downchange. I never did, and doubt if I ever will, try a clutchless change on either bike.
The Norton has done the greater mileage at 76000 miles, against a mere 52000 miles on the Triumph, but has received more attention. Not by me, though, the bike came to me with 22000 miles and a recent, complete engine rebuild that included electronic ignition, hefty main bearings and its first rebore. Apart from the aforementioned head jobs I did another rebore at 47000 miles and fitted new triplex primary chains every 12000 miles. The diaphragm clutch went the once at 39000 miles, producing a lot of clutch slip and some disturbing noises. Most parts are still available from the Norton factory. Use of modern gasket goo has stopped the worst of the oil leaks, although there seems nothing that can be done with the chaincase.
The Triumph is on its final rebore, third set of valvegear but still runs the original crankshaft. The duplex primary chain is longer lived, but the tensioner also needs replacing at 15000 miles. The clutch, a rather more conventional item than the Norton's, needs new plates every 20,000 miles but if cheap pattern plates are used then it'll need attention in a lot less than 10,000 miles. On both bikes, it's important to put high quality parts inside the motor.
The same should go for the chassis as well. I once fitted some cheap pads in the Lockheed front disc. After about 200 miles they broke up when I braked from 40mph for a junction. I had to lock up the back wheel and pop the bike into first gear to pull up in time. Even under that extreme abuse the chassis retained its poise. Unflappable was its best description. The rear drum was a delight to use and didn't wear out its shoes for tens of thousands of miles. When set up properly, with decent pads and Goodridge hose, the front disc was adequate to the Commando's speed but a little bit wooden in feel. The lack of feedback intensified when the brake fluid went off or the pads, which lasted about 8000 miles, were near the end of their life. Wet weather wasn't exactly fear inspiring, but if a light caress of the lever every few minutes hadn't removed the layer of water then there was a mind dislocating period of lag before they gripped. When they did grip they did so progressively enough to avoid locking up the wheel on a wet road.
The Triumph's drums were a bit of a mixed bag, as well. The conical hubs were a beautiful sight to behold, but the front had a curious push-pull operation of its TLS unit that needed meticulous attention to its adjuster every 500 miles and a newish brake cable (figure about 5000 miles). When it was set up well, the braking was fierce enough to lock up the wheel but sensitive enough to be really nice in the wet. When it went off, it became grabby in the dry and very unpredictable in the wet. The rear drum had no such suicidal tendencies but could have done with a touch more feel. Shoes lasted about 12000 miles at each end.
Overall, I preferred the Norton's set-up, but there wasn't enough in it to make it a reason for choosing one machine over the other. It's possible to fit the older TLS drum front brake from the late sixties version of either bike, so if they really become too dodgy a relatively cheap and effective solution is at hand.
Suspension was similar but different. Both machines had a set of Girling shocks, although the canted forward nature of the Norton's gave a more supple ride than the near vertical Triumph's which often seemed rather harsh. The Norton certainly had the better forks, inherited from their acclaimed Roadholder series that had good damping and perfectly matched springing. Again, the Triumph front end was less sophisticated, giving the bike a rougher, edgier feel on today's ruined road surfaces. Not that it was ever bad in the sense that it let the Triumph wobble or weave, but jumping from one machine to the other showed that the Norton had a more sophisticated ride.
With its slightly dubious shimming of the Isolastic mounts the Norton needs all the edge it can get. The shims needed attention every 2000 to 3000 miles, depending, it seemed to me, on how heavily loaded was the chassis. Both sets of forks eventually wore out. It was relatively easy to buy new bushes and seals for the Norton but I ended up buying a new set of forks for the Triumph. The latter felt less assured on knackered forks than the Norton.
Both machine's electrical systems have evolved in an identical manner. With the exception of the alternator, all the Lucas electrical bits have been pulled off and thrown away. Replaced with some Japanese solid state bits, I'm sorry to say, and a big car battery. Lights are halogens but the Norton's lasts twice as long, which reflects the amount of vibration getting through to the chassis. Switches, electrics and wiring on the stock bikes are total crap after a couple of years wear and should be junked in the unlikely event that it hasn't been done already.
Both bikes have a voracious need for oil, the Triumph having a slight tendency to crack its frame, letting oil leak out of its reservoir. The oil cap in the frame (at the front of the seat) is actually a valve cover - cynics might suggest that it can be used to replace one of the valve covers when they vibrate off but this would leave you with a lap full of lubricant! Because a lot of oil's burnt off or leaks out I only change it every 3000 miles, which seems about right for these motors which have only the most basic of lubrication systems.
If I had to chose one machine then it would probably be the Norton as my riding tends towards the long distance. If I was going to use one of these bikes for commuting and charging down country lanes then the Triumph would have the edge. Prices for a good example of either are in the thousands rather than hundreds with the venerable Interstate fetching an extra grand over the Triumph, running if rough examples of which can be bought for about £750. But they will need two times that amount spent to bring them up to scratch. The great pity is that there is no modern interpretation; a fun big twin with an excess of torque that can be run on the same kind of money as a Honda C90.
Tom Laing