The 1950s and ’60s were the era of the UBM — Universal British Motorcycle — a parallel OHV twin sitting upright in the frame, in the 500cc to 750cc range. The original UBM was the Triumph 5T Speed Twin of 1938, soon to be copied by half a dozen of the major British motorcycle companies. Matchless, which built its first motorcycle at the Plumstead works in southeast London around 1901, came up with its own version in 1948, the 498cc G9, with a 66 x 72.8mm bore and stroke. And a fully sprung frame, with a swingarm rear suspension.

It should be noted that in the 1930s Matchless bought the AJS marque and the company became Associated Motor Cycles, Ltd., or AMC, the major difference between the two brands being the lettering on the gas tank.

The G9 engine differed from other UBMs in that it had a third bearing on the crankshaft, between the two connecting rods, to give added strength. The engine’s dry sump lubrication system used the camshaft to run two oil pumps, one on each side of the crank, aiding in efficient lubrication; apparently these engines could go 75,000 miles before any major work was needed. Quite remarkable for a UBM of the era, when top-end jobs were often done at 20,000 miles, bottom-end at 40,000.

The two cylinders were separate, as were the heads, and while this seemed to work well with the 500, as the engine grew larger the lack of rigidity appeared to enhance vibration. During the 1950s most factories increased the size of the engine, with 650cc being considered the maximum reasonable size for a UBM, due to those vibratory concerns. In 1955 Matchless elected to bore out the engine to 72mm for an increase to 593cc — called a 600, designated as a G11. This was followed by the G11CS, or Competition Sprung, a street-legal scrambler with easily removable lights, and the G11CSR, a more roadworthy version, often called the Coffee Shop Racer. The CS models came with higher compression ratios and other performance enhancements…and often more problems. The frame used a single downtube to meet up with the full cradle holding the engine.

In 1958 Matchless offered 17 different models, including the first G12 650. The very important American market had been demanding that 650, the dealers needing it to compete with the Triumph and BSA 650s. Small problem: the engine could not be bored out any more. Solution: increase the stroke to 79.3mm, or 646cc. That was the G12, with the basic road-going model having valanced fenders and a reliable 7.5:1 compression ratio, and two sportier CS models with an 8.5:1 compression ratio and light alloy fenders.

The restroked engine required a new crankshaft, made of “nodular” iron, which flexed enough to reduce vibrations. It was also designed to incorporate a Lucas alternator, though still with six-volt electrics. A new frame with twin downtubes now welded to the full cradle was developed, which did help in reducing the vibration inherent in a 650 vertical twin using a 360-degree crankshaft, although the single-tube frame was also used. The motorcycle seen here, which was built from bits and pieces, has a 1961 G12 engine in a 1959 single downtube frame. An AMC Teledraulic fork is up front, a pair of Girling shock absorbers at the back.

Gas tanks varied in size according to the model and year, but this ’61 G12CS carried only two gallons, all you would need in a race, and was said to weigh 425 pounds with a full tank. And with 5.3 pints of oil in the reservoir.

Other changes occurred over the G12’s years, including 12-volt electrics, sending out decent visibility from the seven-inch headlight. The basic G12 had 18-inch wheels, while this CS was running 19-inchers. Distance between the axles was a little more than 55 inches. Brakes were single-leading-shoe drums, an eight-incher on the front, seven on the back.

One interesting bit of history is that the Matchless marque was originally sold in the U.S. by Californian Frank Cooper, who became the AMC importer around 1946. He did quite well selling singles to win desert races, though the twins were not as popular.

In 1953, AMC acquired financially troubled Norton, although Norton production and sales remained quite separate, the U.S. importer being Joe Berliner, or J.B. Then, in 1960, AMC bought the Indian Sales Corp., which had been selling rebadged Royal Enfields — this was to get the Indian dealers, such as they were, to sell Matchboxes rather than Royal Oilfields. And AMC summarily fired Cooper, after 14 years of good work.

However, AMC filed for bankruptcy in 1962 (Cooper must have laughed), resulting in Matchless being merged more closely with Norton, and Berliner having to deal with Matchless as well. In early 1963, J.B. Matchless Corp. put a full-page ad in Cycle magazine promoting the G12CS and G12CSR…along with the 750cc G15 Matchless, which looked surprisingly like the Norton Atlas model that had appeared in 1962. In 1963 that old 1952 Matchless/Norton arrangement, keeping them separate, changed drastically as bill collectors were pounding on both doors, and Norton production moved from its old Birmingham factory 100 miles southeast to Plumstead.

Not surprisingly, interest in the G12 waned considerably. The last Matchless ad I could find in a U.S. moto-mag was in Cycle’s July 1966 issue, featuring the Atlas-based G15, and mentioning one G12CSR and two G80 singles. At the time British bureaucrats, knowing nothing about motorcycles, thought they could save the industry by merging Matchless, AJS and Norton into the company of an affluent entrepreneur and racecar driver, Dennis Poore. Poore was already looking after the Villiers engineering firm, which made most of the British two-stroke motorcycle engines. The Matchless and AJS names dropped from sight, and the new company was called Norton-Villiers.

Source: RiderMagazine.com

This has to be one of the least-known motorcycles built since the end of World War II, with an Ariel 4G Mark II Square Four engine bolted into a Roger Slater frame. The photo model is one of the two prototypes, and lacks some of the amenities of the production versions – such as the side panels.

The Healey 1000/4 does not appear to be listed in any of the popular motorcycle encyclopedias, and the only major mention to be found in motorcycle histories are some three pages in Roy Bacon’s “Ariel – The Postwar Models.” I remember reading something about it in an American motorcycle magazine in the early 1970s, but that is about it. After punching a few keys on my computer a dozen different sites come up, with varied information. Any number of articles have probably been written about this bike in British magazines, but apparently those stories are not online.

Starting at the beginning means back to the first 997cc OHV Ariel 4G engine. An earlier, smaller, OHC version existed, but we’ll leave that out. That 4G was around from 1936 to 1959, with Ariel advertising Squariels that last year, along with the new two-strokes.

The biggest problem with an air-cooled square four is that the front cylinders do fine, but the rear pair can overheat. Over the quarter-century of the 4G’s production – minus a couple of years due to the war – there were continuous upgrades in the run that totaled some 12,000 bikes. The final Mark II version had an alloy cylinder block with pressed-in barrels, and a lightweight alloy cylinder head with a slightly X-shaped induction manifold feeding all four cylinders via just one SU carburetor. A single transverse camshaft operated the eight valves. Two separate cast aluminum exhaust manifolds ran four separate header pipes, better for cooling. The dry sump engine had eight pints of oil in the reservoir. The oil-bathed primary chain ran back to a dry clutch, and the four-speed gearbox was a Burman GB.

The original purpose of this model was to haul sidecars, so it did not have much in the way of horsepower – around 40 with the 7.2:1 compression – but bags of torque. Sprinting, the British word for drag racing, was popular in the 1950s, and a stock Mark II, being rather hefty, ran in the mid-15s with a speed of around 85 mph. One fellow put a supercharger on a Vincent V-twin and turned 11.3 seconds in 1958, but when somebody tried that with a 4G, it ended with a big BANG! as the cylinders separated from the crankcase.

A pair of brothers, George and Tim Healey, liked playing around with the 4Gs, and were sprinting them in the 1960s. Some time after Ariel shut down 4G production, the Healeys began gathering up the unsold stock. They had a shop in Redditch, a few miles south of the Ariel factory, and by 1967 the spares were running out and building replacement parts had become their full-time business, called the Ariel Sq4 Specialists. Then they decided to build their own motorcycle.

The old Square Four had a rather basic, and heavy, cradle frame, with an Ariel fork and Anstey-link plunger suspension at the back. The boys got in touch with Slater, who was making tubular spine-type frames for Vincents under an agreement with Fritz Egli (read about the Egli-Vincent here). Could he make a similar design for the Square Four? Not a problem. Essentially the engine was suspended from the frame, using half a dozen through-bolts. Up front a turnbuckle went from the steering head to the crankcase – just in case there might be a similar BANG!, this would prevent the crankcase from falling to the road. Slater built the prototypes, and production versions were manufactured in Redditch. The oil supply was held in the backbone, with the Healeys putting in an improved lubrication system and bolting an oil cooler on up front.

Metal Profile, a noted company that supplied forks to many British motorcycle companies, made the front fork, with tapered roller bearings used at the head. Rear shocks were by Girling, with two-way damping. Brakes were Italian, a powerful alloy drum having a pair of two leading shoes to slow the front wheel, single leading shoe at the back. Spoked wheels were both 18-inchers, with a 3.25 tire on the front, a 4.00 on the rear. The large gas tank on this prototype was a Slater design, but when the bike went into production, a more refined style was used. Instruments were speedo, tach, ammeter, sitting above a seven-inch headlight; a little clock was added to the production dash.

End result was somewhat impressive. Better cooling and lubrication allowed the compression ratio to be upped to 7.5:1. The Healey advertising said the 1000/4 put out 50 horsepower, 10 more than the old Mark II. Potential self-destruction kept radical changes at bay. Wheelbase was 57 inches, seat height 30 inches, and ground clearance at the unprotected sump was 7.5 inches. Most impressive was the weight, 355 pounds dry, 80 pounds less than the Mark II.

The first showing of a production bike was at Britain’s big motorcycle show in late 1971, and improvements went on over the next six years, ending with disc brakes and mag wheels, Italian fork and shocks. But the price was high, more than the new-in-1975 Gold Wing, and the company shut down in 1977. Precisely how many production models were built and sold is not known, but 18 seems to be a fair number. Plus nine or 10 kits for people who already had the 4G engine. Collectability? A Healey sold at auction for $40,000 in 2016.

Source: RiderMagazine.com

This little charmer was in the first wave of Japanese bikes to enter the U.S. market, thanks to Hap Jones, a motorcycle racer and businessman of considerable note. Hap had been selling British bikes in the 1950s, and then decided to get out of the retail business, focusing on his more profitable distribution side. And the Japanese manufacturers were just getting interested in American buying habits, with Honda opening up for business in 1959, Yamaha in 1960.

So Hap got on the phone to Japan in 1961 and had a chat with the Tohatsu suits, who were undoubtedly very happy at the thought of getting into the burgeoning U.S. market, especially with a well-known and highly respected gent like Hap Jones. They arranged for a couple of 50cc Runpet models and several 125s to be sent over, a deal was struck and Hap introduced them to the world with a full-page ad in the January 1962 issue of “Cycle” magazine…quite unusual for a start-up to spend that kind of money. Then he had the good fortune to have a rider on a Tohatsu 125 win the lightweight Sportsman road race at Daytona, which gave him great publicity. Within a few months he claimed to have 300 motorcycle dealers and a number of sporting-goods stores carrying the Tohatsu line.

What was this little Runpet Sport? And this Tohatsu Company? The word is a combination of Tokyo and “hatsudoki” (engine factory), the origins going back to 1922 and the Takata Motor Research Corp., which made its reputation by building a small motor for a highly successful rail-track car. The name was changed to Tohatsu in 1939, and the company became focused on producing military equipment, including small motors to run little generators. War came and went, the factory survived, and it began selling these little motors to other companies building motorized bicycles. “Heck, we can do that ourselves,” some executive said, and Tohatsu began selling kits for bicycle owners to mount themselves, with gas tank, exhaust system and bracketry.

Better yet, it would build a sturdy bicycle, with a telescopic fork. In 1953 the Puppy appeared, powered by a 58cc two-stroke. Not a very attractive vehicle, but mildly efficient. In the mid-’50s the Japanese were all desirous of personal transportation and some 80 companies were competing in the motorized two-wheeler market. By 1956 Tohatsu was the biggest of the lot, selling 70,000 motorbikes, twice the number that Honda was. But competition was getting fierce, and the serious outfits like Honda, Yamaha and Bridgestone were busy modernizing their products, while dozens of the small operations were shutting down. Unfortunately Tohatsu’s success was followed by some major financial mismanagement, with lots of borrowing going on to keep the company afloat. In 1960 the government, through something called the Rehabilitation Act, arranged for Tohatsu to be bought by the Fuji Electric Manufacturing Corporation, the presumption being that this larger concern might be able to get Tohatsu back on its financial feet.

Motorcycles were just a part of the Tohatsu Company, with marine hardware, from bilge pumps to outboard motors, being more important. However, the two-wheeler R&D boys had been hard at work with new models now at hand, including the 50cc Runpets, the Japanese advertising saying in translation, “…with the accent on having fun!”

The Runpet Sport was indeed a sporty creature, with a highly tuned 49cc piston-port engine, fed through a TK carburetor that, like the Amals of the day, had both a tickler and a choke. A single-disc clutch connected to a three-speed gearbox. The factory claimed it put out 6.8 horsepower at 10,800 rpm and was capable of speeds in excess of 60 mph. Quite astounding for a street-worthy little single! It should be noted that 50cc racing was quite popular back then, especially in Japan.

Unfortunately Tohatsu did not get into developing automatic oiling, and owners had to do things the un-fun way, mixing the oil with the gas. As well as kickstarting the tiny terror. Tohatsu had put an electric starter on its basic Runpet with a lower state of tune, intended for the commuter and housewife, but the Sport was to live up to its name.

Chassis was simple, with a large tubular steel backbone frame from which the engine hung, two bolts securing the head; two more were down at the back close to the swingarm pivot. A telescopic fork up front. Two pairs of arms went back from the main frame to hold the saddle and places for bolting the tops of the two shock absorbers.

The 17-inch wheels had drum brakes, and the distance between axles was 44.5 inches. A 100 mph speedometer (rather optimistic) sat in the headlight nacelle, and a very small windshield served to enhance the sport look. A short saddle and no passenger pegs indicated that this was a one-up ride. But you could get the groceries, as there was a small luggage rack and two tiny pannier bags, made from the hide of a Nauga. Total weight was 135 pounds.

There were several options as to presentation, and this one has the scramblerish high pipe and small skid plate. Shiny chrome fenders and nice paint on the tank and side panels enhanced the image. The company was also putting out new two-stroke models, designed with American riders in mind, like a 125 parallel twin with four gears and 15 horsepower.

All to no avail. Bankruptcy was declared in 1964 and the motorcycle side was shut down. We don’t know how many Runpet Sports were sold by the 300 dealers Hap Jones claimed were carrying the brand, but there don’t seem to be many in the used-bike lists.

Source: RiderMagazine.com

This was the bike that got a lot of Americans excited about the Norton marque. Brit bikes were relatively rare in the U.S. in the early 1950s, with mainly Triumph and BSA battling it out. Yanks had long read about Norton’s racing successes, like when a 500 Manx came in second at Daytona in 1949, but were not much interested in the single-cylinder Internationals, civilianized versions of the racing Manx. What they wanted was an easy to start twin, with enough zip to run up to the semi-magical 100 mph mark. The 500cc Dominator 88 did not quite have the punch needed, but when it was bored and stroked to 600cc (actually 597cc), that stoked some serious interest.

Some people, both industry and consumers, were a little surprised that Norton had not gone to the popular 650 size, which Triumph had done in 1950 with the Thunderbird, and BSA a year later with the Golden Flash. Nortons began to be imported in 1949, and had six U.S. distributors. After the arrival of the 99 the distributors apparently got together and jointly bought the first full-page ad seen in the bike magazines–in the November ’66 “Cycle.” After a very complimentary road test in the September issue.

Norton was an old company, with James Lansdowne Norton founding the Norton Manufacturing Company at the age of 29, back in 1898, when it started manufacturing chains for the burgeoning bicycle market. But motorized bicycles were the coming thing, and JLN got right on it. His 690cc Peugeot-powered V-twin, a touring model, won the Isle of Man Tourist Trophy in 1907; success was clearly in the stars. Norton began building its own engines and prospered.

Late in 1945, after WWII, Norton went back to building civilian motorcycles, both a side valve and an OHV 500 single, along with a very few OHC 350 and 500 Internationals. Triumph was hitting the advertising pages big time, promoting its sleek T100 Tiger 500cc twin, and that was getting a lot of attention. So Norton did the logical thing and hired a designer named Bert Hopwood, who had worked at Triumph before the war when the T100 first came to light. He joined Norton in 1947, improved the singles, and then worked on developing a parallel twin. In November of 1948 the Dominator Model 7 showed up at the annual Earl’s Court motorcycle show, with a vertical twin engine mounted in a Norton frame with a telescopic fork and a plunger rear suspension. Unfortunately, at 440 pounds it was 75 pounds heavier than the Triumph. In 1949 Hopwood moved on to the BSA company, assigned to the task of making BSA’s 500 twin into a 650.

Norton went to work bringing the Dominator 7’s weight down, and the big innovation was the advent of the Featherbed frame, originally intended for the racing Manxes. Previous frames had been complicated and heavy, whereas the Featherbed was essentially two one-piece loops that was both lighter and stronger, using expensive Reynolds 531 manganese-molybdenum, mild-carbon steel tubing. Since everything passes through the steering head, the backbone tubes were welded to the bottom of the head, while the downtubes actually ran between the backbone tubes and then welded to the top of the head. All suitably braced.

Norton then went about making a roadster edition of the frame, using less expensive steel. Initially the saddle-supporting rear section was bolted on, but soon was welded, as that was a lighter approach. Norton also saw fit to give the frame its own name, plus a secondary description, which began with Wideline, and then Slimline (1960), referring to the width of the frame beneath the forward part of the saddle. The 99 used an oil-damped Roadholder fork and a swingarm rear end with a pair of Girling shock absorbers. When the 500 Domi 7 twin got the Featherbed, the bike received new numeration: Domi 88.

Move forward to 1955, and we find Mr. Hopwood being invited to rejoin the Norton Company. And soon the 497cc 88 had a larger sibling, the 597cc 99, the 100cc gained by using an even longer stroke…the 88 having a 66 x 72.6mm bore and stroke, the 99, 66 x 82mm.

Nothing exceptional about the dry-sump engine. The crankcase was split vertically, the cylinders were iron, the head aluminum alloy. The camshaft was up at the front of the engine with four light-alloy pushrods operating the four valves. A single Amal Monobloc fed the fuel to the combustion chamber, having a modest compression ratio of 7.6:1.

A single-row primary chain ran in an oil bath from the crank to clutch, which had little rubber shock absorbers. This was all done inside a sheet-metal primary case. And if the cork gasket was in good shape, the oil stayed inside. The four-speed transmission was made by Norton, and in best British tradition, the shift was on the right side, up for first.

The bike weighed some 410 pounds wet, and put out 31 horsepower. It had a comfortable seat, slightly Americanized handlebars and a 4.4-gallon tank–test write-ups said the 99 got more than 50 mpg. The headlight shell held a speedometer, ammeter and light switch. Initially a Lucas magneto sparked the plugs and a dynamo lit the seven-inch headlight, but in 1958 a crankshaft-driven alternator and distributor did both tasks. Petcock on, choke if cold, tickle the carb, fold out the starter and a healthy kick or two would get the engine going.

That “Cycle” road test reported a top speed of 114 mph–impressive. And a quarter-mile time of 14.61 seconds. Equally impressive.

The years went on. In 1961 the 99SS version appeared, with twin carbs. Last official year for the 99 and 99SS was 1962, replaced by the 650SS, now stroked to 89mm to get the additional 50cc.

Source: RiderMagazine.com