Tag Archives: Retrospective

Retrospective: 1960-1964 Tohatsu CA2 Runpet Sport 50cc

1962 Tohatsu Runpet Sport 50cc
1962 Tohatsu Runpet Sport 50cc. Owner: Cliff Shoening, Bremerton, Washington.

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.

1962 Tohatsu Runpet Sport 50cc
1962 Tohatsu Runpet Sport 50cc. Owner: Cliff Shoening, Bremerton, Washington.

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!”

1962 Tohatsu Runpet Sport 50cc
1962 Tohatsu Runpet Sport 50cc. Owner: Cliff Shoening, Bremerton, Washington.

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.

1962 Tohatsu Runpet Sport 50cc
1962 Tohatsu Runpet Sport 50cc. Owner: Cliff Shoening, Bremerton, Washington.

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.

1962 Tohatsu Runpet Sport 50cc
1962 Tohatsu Runpet Sport 50cc. Owner: Cliff Shoening, Bremerton, Washington.

Source: RiderMagazine.com

Retrospective: 1974-1979 Kawasaki KZ400 Twin

1976 Kawasaki KZ400
1976 Kawasaki KZ400D3. Owner: Michael Lane, Kansas City, Kansas.

Nice little bike. Great for commuting, but entirely capable of a cross-country trip. This model was an answer to problems in the global economy. The dollar was devalued in 1971, with President Nixon taking us off the gold standard, meaning we had less money to spend on foreign products. Also, Congress was upping the import tariffs on lots of things, trying to figure out how to pay for the war in Vietnam. In response, Kawasaki decided to build a factory in Lincoln, Nebraska. This was not a real manufacturing facility, but more of an assembly plant, as the import duties on bits and pieces of a motorcycle were a lot less than bringing in a whole one.

1976 Kawasaki KZ400
1976 Kawasaki KZ400.

Kawasaki had been looking at the success of Honda’s little four-stroke twin, the CB350, which had modest performance but all the amenities Americans seemed to like, including an electric starter. Kawasaki’s R&D backroom boys put their heads together, drew up plans and came forth with a very efficient, if rather uninspired, 398cc vertical twin, with a 360-degree crankshaft, an overhead camshaft and an electric leg. In June of 1974 the first KZ400 rolled off the assembly line in Akashi, Japan, and a number of them arrived in the United States. But that was just the beginning, as the factory was turning out a lot more parts than those assembly line workers could use. Crates of them were going to Nebraska. In January of 1975 a KZ400 rolled off the Lincoln line with “Made in the USA” on the ID plate.

One should add that the price of gas went up 45 percent between 1973 and 1975, from 39 cents per gallon to 57 cents. Could there be a better time for a 50-mpg econo-bike to hit the market?

1976 Kawasaki KZ400
1976 Kawasaki KZ400.

The frame was a simple double cradle having dual downtubes, with a big, fat backbone tube meeting up with the cradle at the swingarm pivot, a very solid affair that avoided any notion of flexiness. Front fork was by Kawasaki, very much like a Ceriani, and on the inexpensive, non-adjustable side. Five inches of travel was good, with a 27-degree rake and trail of approximately four inches offering a very middle-of-the-road stance. The swingarm ran out 20 inches, bouncing along on a cheap pair of Kawasaki shock absorbers having preload adjustability and three inches of travel. Too soft, reviewers said.

Spoked wheels were both 18 inchers, the front carrying a 3.25 tire, the rear, 3.50. Braking was done by a single 226mm (10.91-inch) disc on the front, a 180mm (7.09-inch) drum on the back. As a polite reviewer might say, adequate. But this was not intended for sporting riding like the Z-1, and the brakes worked fine for commuter use. Distance between the axles was 53.3 inches.

The wet-sump engine was straightforward, being slightly oversquare with a 64mm bore, 62mm stroke. Of minor note was the chain-driven counter-rotating balancer system down in the crankcase, called “harmonic” by one reviewer. It did not smooth out all vibrations, but for anyone happy to ride at two-thirds of redline (9,000 rpm) it was entirely adequate. Commuters, the intended buyers, were not known as rip-snorting riders.

1976 Kawasaki KZ400
1976 Kawasaki KZ400.

The four valves, two per cylinder, were pushed down by a single overhead camshaft, and 36mm Keihin CV carbs fed high-test gas (preferred) and air into the combustion chambers, where it was compressed 9:1. The engine was rated by the factory at 35 ponies, which was usually measured at the crankshaft, not the rear wheel; on a dyno it was closer to 29. Respectable; good for an honest 90 mph. In 1977, with the fuel crisis in the headlines, the carb size was reduced to 32mm to enhance mileage figures a little. And the compression was raised to 9.4:1, which served to create roughly the same power output. Ignition was by battery and single two-feed coil. Starting was by button, except a kickstarter was there as a backup, as many Americans did not yet fully trust electrically powered gizmos.

1976 Kawasaki KZ400
1976 Kawasaki KZ400.

Primary drive was via a Hy-Vo chain, and then through a wet clutch to a five-speed transmission and chain final drive. The long, flat saddle was great for one person, a bit crowded for two. Looks were OK, with shiny chrome fenders and nice paint on the 3.2-gallon gas tank and side panels. Curb weight was a shade more than 400 pounds. The only complaint seemed to be about occasional oil weepage coming from around the head.

The number of KZ400 models expanded. The D series, the essential KZ400 that we have here, went from ’74 to ’77 and cost $1,170 in ’74. The cheaper S series, with a drum front brake and no electric starter, went for $995 in ’75. And for one year, ’77, there was the A model, with small handlebar fairing, saddlebags and luggage rack.

1976 Kawasaki KZ400
1976 Kawasaki KZ400.

For ’78 the D designation became a B, with a redesign in the head, a slightly different gas tank and mufflers, an extra gear in the transmission and the fuel tap getting a diaphragm. The low-price version stayed with five speeds and had a two-into-one exhaust. And there was the stepped-saddle LTD “custom” model, with cast wheels.

This modest motorcycle was also a modest financial success. Kawasaki ran a lot of entertaining ads focused on the commuter, one saying, “More fun than any car I ever drove.” This ’76 model, in the same family since new, is quite stock except for the MAC mufflers.

For 1980 the engine was bored out to 67.5 mm, a 10 percent increase in size, and received a new KZ440 designation, giving the basic design four more years of life.

Source: RiderMagazine.com

Retrospective: 1968-1973 Honda CL350 Scrambler

1968 Honda CL350 Scrambler
1968 Honda CL350 Scrambler. Owner: Jack Wagner, Grover Beach, California.

Honda motorcycles opened for business in the American market in 1959, when the four-stroke 50cc Super Cub came on the market. And over the next 10 years the company acquired a very positive reputation, well deserved, for having high revving, hard hitting, highly dependable products, especially with its 305 series, like the CB77 Super Hawk and CL77 Scrambler.

But, as we say about horses, the 305s were getting a bit long in the tooth. What to do? Shouldn’t cost too much because lots of money was going into the carefully kept secret–the four-cylinder CB750. Having a different number would be good, from 305 to 350. The bore was increased from 60 to 64mm, the stroke reduced from 54 to 50.6mm, the true size of the “new” engine being only 325cc. No matter, as minor exaggeration is considered to be quite acceptable in the advertising world.

Honda used it in three models, the 1968 CB Super Sport and CL Scrambler, and a year later the SL Motorsport. All told, more than 600,000 of these 350s were sold in the U.S. over the six years of production, which means a lot of them are probably still stashed in old barns or forgotten behind the junk in the back of the garage. Here we are dealing with the Scrambler version, better characterized as a street-scrambler, having only minor pretensions to being competent off the pavement. It was a styling thing, much like the “adventure” bikes of today, with the rider liking to think that he can dash across the Gobi Desert any time he wants. Or, more likely, he wants other people to think that.

1968 Honda CL350 Scrambler
1968 Honda CL350 Scrambler. Owner: Jack Wagner, Grover Beach, California.

The essence of the scrambler style were those upswept pipes, curving individually around the left side of the cylinders and ending up in one large muffler that held a permanent spark arrester. Which was covered by a black heat shield for the first two years, and then the shield was chromed. Interestingly, the shiny header pipes were pipes within pipes, the ostensible reason being that the owner would not have to put up with the inevitable bluing that arrived with time. A secondary reason, which should really be the primary, was that the actual pipes carrying the exhaust were quite small in order to maintain a high exhaust-gas velocity that was essential to the tuning system.

This whole CL exhaust shebang weighed a substantial 24 pounds, and was responsible for a loss of several horsepower compared to its CB sibling, which had a longer, more efficient exhaust. Power was 33 horses at 9,500 rpm in the CL, compared to the CB’s 36 at 10,500, despite the engine internals being identical. CL owners usually ignored the redline on the tachometer dial.

1968 Honda CL350 Scrambler
1968 Honda CL350 Scrambler. Owner: Jack Wagner, Grover Beach, California.

Another Scrambler notion was the larger front wheel, 19 inches as opposed to 18. This was more about looks than performance, with the more serious off-roader, the SL, having a 21-incher. Front fender was slightly abbreviated, and the gas tank held 2.4 gallons, almost a gallon less than the CB’s. There were also rubber gaiters on the CL’s fork legs, always good for the daredevil look.

Those were the differences, now for the similarities. Looking into the powertrain, the parallel twin used alloy cylinders with iron liners, and the oversquare engine had lots of possibilities for revs–10,500 of them! In 1968 street-going four-strokes were not known for spinning ten thousand times a minute, and the less knowledgeable thought that this would mean a brief lifespan. But ten grand! How did they achieve that? First, there was a single overhead camshaft, spun by an endless chain between the cylinders. And the camshaft itself was a solid piece of work, weighing some three pounds.

1968 Honda CL350 Scrambler
1968 Honda CL350 Scrambler. Owner: Jack Wagner, Grover Beach, California.

But how does one get valves to seat properly at that speed? The valves all had dual coil springs, but the springs themselves were wound progressively, so that there was relatively less tension when the valve was seated, increasing greatly as the valve got pushed down. Carburetion was a pair of 26mm Keihin constant-velocity units using neoprene diaphragms.

The crankshaft, with four main bearings, spun using a 180-degree firing order as on the 305, but was a lot smoother due to excellent balancing. Primary drive was via straight-cut “paired” gears that were both efficient and quiet. Honda knew that the popular helical gears were quiet but not overly efficient, and came up with this mildly complicated system. A multi-disc wet clutch passed power through a five-speed transmission (up a gear from the 305) and out via a chain running along the left side of the rear wheel.

The chassis was not a notable construction, but suitable for delivering a good feeling to the rider. The backbone was a pressed-steel stamping, which was falling out of aesthetic favor at the time, though inexpensive to make. Fortunately it was hidden beneath the gas tank, and the viewable bits were mostly tubular, a single tube coming down from the steering head to spread into a double cradle.

1968 Honda CL350 Scrambler
1968 Honda CL350 Scrambler. Owner: Jack Wagner, Grover Beach, California.

Suspension was adequate, with a telescoping fork at the front and a pair of DeCarbon-type shocks at the back. A 3.00-19 tire was on the front wheel, 3.50-18 at the back. A double-leading shoe drum brake did yeoman’s service at the front, a single leading shoe at the back. It had 52 inches between the axles, and a wet weight of around 370 pounds.

The saddle, about 32 inches high, was long and flat, while the upswept handlebars had the mandatory cross-brace, part of the scrambler look. The rider saw separate speedo and tach above the headlight. Fenders were chromed, with excellent paint on the gas tank and side panels. And the essential electric leg for starting.

Price was $700, less than half that of the 750 four. Which is why these middling bikes outsold the big one…though we can only presume that quite a few 350 owners upgraded to the 750.

Source: RiderMagazine.com

Retrospective: 1969-1971 Yamaha DS6-C 250cc Street Scrambler

1969 Yamaha DS6-C Street Scrambler. Owner: Ed Heckman, Paso Robles, California.
1969 Yamaha DS6-C Street Scrambler. Owner: Ed Heckman, Paso Robles, California.

For more than 10 years 250 two-stroke twins were the mainstay of the Yamaha range here in the United States, from the DS1 of 1959 (though not sold in the U.S. until 1961) to the DS7 of 1972. We have no idea what the DS stands for, but doubt that it has anything to do with the DS prefix used in Yamaha’s music department. Two-strokes were the popular engines for sporty bikes in the 1960s, being reasonably powerful and inexpensive to make. Running against this 250 DS6 were Suzuki’s Hustler and Kawasaki’s Samurai, all in the $600 range. Any college student having a few bucks in his pocket could probably arrange time payments with the local dealer…backed by Dad’s signature.

When Yamaha advertised this quarter-liter as having 30 horsepower, interest was great. And it passed the eye test as well, with high pipes, one on each side. This was styled as a dual-purpose machine–hence the C in the alpha numerology. The chassis design was much more favorable to the street rather than the trail, so the high pipes were more a styling point rather than functional.

1969 Yamaha DS6-C Street Scrambler. Owner: Ed Heckman, Paso Robles, California.The history of the DS6 engine was long and had the distinct advantage of being associated with Yamaha’s racing 250, the TD1, which had great success over the previous decade. Riders could thank Yamaha’s racing shop for improvements, as the company was intent on keeping its 250 riders on the podium. And what is good on the track can be tuned down to find its place on the street. Any time the engineers improved the racer, they would try to figure out a way to adapt whatever it was to the street bike. Ads for the DS6 promoted the TD’s Daytona wins in 1967 and 1968.

The DS6 246cc engine was of piston-port design, with the 56mm bore and 50mm stroke that had been around for 10 years. This was a genuine five-porter, the ports being cast into the aluminum cylinders with cast iron liners. The new for ’69 cylinders had three transfer ports, along with intake and exhaust, allowing for a larger fuel charge to find its way into the combustion chambers faster. Compression ratio was a reliable 7.3:1, and the cylinders now had copper head gaskets to replace the earlier aluminum ones–which had a tendency to fail when pushed very hard. Naturally these new gaskets came from the racing TDs. Inside the engine were race-worthy bearings, though they would never be subjected to the 10,000-plus rpm attained by TDs. Those 30 advertised horses were said to be generated at 7,500 rpm, and were certainly taken off the crankshaft rather than the rear wheel. Road tests merely quoted the “claimed bhp.”

1969 Yamaha DS6-C Street Scrambler. Owner: Ed Heckman, Paso Robles, California.Two 26mm Mikuni VMC two-stroke carbs combined with Yamaha’s Autolube system fed the fuel/oil mixture into the crankcase. Yamaha was noted for having developed the Autolube system, using a separate container for oil rather than messily mixing it with gas in the tank. It was being used on Yamaha’s race bikes in the late ’50s, and then adapted to street machines in the early ’60s. The greatest advantage to Autolube was that it could closely regulate the amount of oil to be mixed with the gas, so instead of having a steady 20:l mixture, which could get quite smoky at times, the oil was metered by both engine speed and the opening of the throttle valves. This could diminish oil input when idling through town, and give it an almighty whack when the rider decided that a full-on accelerator rush down a country road was in order. The oil capacity was three pints, which was good for half a dozen fill-ups of the 3-gallon gas tank.

1969 Yamaha DS6-C Street Scrambler. Owner: Ed Heckman, Paso Robles, California.Crankshaft power ran back the left side via helical gears to a seven plate clutch, blessed with six torsion springs that helped to absorb even the most abrupt of gear changes. And rubber cushions in the hub helped reduce vibration. Smoothness was what the rider felt when going through the five gears. All this sat securely in a tubular steel double-cradle frame, which looked remarkably like that on a race bike.

A rather steep 34mm telescopic fork ran down to the 18-inch front wheel, where a 7-inch double-leading-shoe front brake did an excellent job of slowing things down. The rear swingarm had a pair of shocks with adjustments available for spring preload. And the wheel, another 18-incher, also had a 7-inch brake, but with a single leading shoe. The 50.8-inch wheelbase was a quick handler on the street, but would keep the sensible trail rider at a more modest pace.

1969 Yamaha DS6-C Street Scrambler. Owner: Ed Heckman, Paso Robles, California.The look was quite different from the preceding low-pipe DS5, which had a rather bulbous 4-gallon tank, and speedometer and tach built into one unit. The smaller 3-gallon teardrop tank was much more attractive in appearance, and the speedo and tach were now separate…very English. Long, flat saddle and chromed metal fenders added to the good looks, going along with the upswept pipes–which did have protective heat-shielding, but long pants were advisable. Yamaha had dropped a tooth from the DS5 countershaft sprocket, which reduced the top speed a small amount, down to 90 or so mph–depending on the weight sitting on the saddle. And a skid plate was bolted on, more for looks than the thought that this shiny fellow would ever scrape its underbelly.

The DS6-C weight was down 20 pounds on DS5, weighing 304 pounds dry. Much of that had to do with the absence of an electric starter. Firing up this baby was done the old-fashioned way…admittedly a very simple task.

The DS series was a great sales success, lasting until the RD250s took over in 1973.

1969 Yamaha DS6-C Street Scrambler. Owner: Ed Heckman, Paso Robles, California.

1969 Yamaha DS6-C Street Scrambler. Owner: Ed Heckman, Paso Robles, California.

Source: RiderMagazine.com

Retrospective: 1956-1962 Norton Dominator 99 600cc

1958 Norton Dominator 99. Owner: Cliff Schoening. Photos by Ralph Noble.
1958 Norton Dominator 99. Owner: Cliff Schoening. Photos by Ralph Noble.

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.

1958 Norton Dominator 99Norton 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.

1958 Norton Dominator 99Norton 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.

1958 Norton Dominator 99Move 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.

1958 Norton Dominator 99The 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

Retrospective: 1974-1977 Montesa Cota 247-T

1977 Montesa Cota 247-T
1977 Montesa Cota 247-T. Owner: Pete Gray, Atascadero, California.

The Spanish Civil War ended in 1939, and then the rest of Europe spun out of control. Spain sensibly decided to stay neutral in World War II. With a limited domestic market, business stagnated. But by 1944, with the end of that conflict in sight, Spaniards started thinking about the future. A couple of like-minded fellows, Pedro Permanyer and Francisco Bulto, met up and decided that providing their countrymen with basic transportation could be profitable. They built a factory in Barcelona and began producing Montesa motorcycles, little two-stroke singles under 125cc, and had great success. But the partners had their differences, and in 1958 Bulto went off on his own to found the Bultaco motorcycle company.

Permanyer persisted, built larger engines, and in 1965 showed the 247cc engine (21 horsepower at 7,000 rpm) in a Scorpion motocrosser. Several years later a mildly detuned version appeared in the Cota trials bike, and in 1968 the Cota won the Spanish Trials Championship. It should be noted that trials competitions were very popular in Europe, less so in the U.S.

1977 Montesa Cota 247-TIn the early 1970s the Japanese OEMs began modifying some of their competitive 250 dirt models into more civilized trail bikes, or as we might say today, dual-purpose. These had two-up seats, lights, a horn, whatever it took to make them street-legal. Permanyer took note. He had a great 250 engine, seen in motocross, roadracing, enduro and trials versions, so why not turn that trials bike into a trail version for the European street crowd; those countries weren’t quite as fearful of two-stroke emissions as were the Americans. The Cota 247-T (for Trail) was born.

Montesa had about 300 dealers in the U.S., who were doing well with some of the competition bikes. Apparently the importer thought this 247-T could be an added attraction. According to sketchy records the factory produced some 2,300 of them, with very few coming to this country. One reason being that it was expensive compared to the competition.

1977 Montesa Cota 247-TThe Owner’s Manual, in Spanish, English and French, begins well: “The MONTESA motorcycle which model is introduced here do (sic) not require an excessive care for maintenance, only a minimum attention is required to ensure a long and perfect serviceable time.” Truth, as the Cota is a delightfully basic machine.

The oversquare piston-port single cylinder has a bore of 72.5mm, stroke, 60mm, with a compression ratio of 10 to 1, generating some 19 horsepower at 6,500 rpm. Ignition is via a flywheel magneto/alternator and coil. The header pipe goes out the left side, high up, with a two-part muffler and spark arrestor. A respectable muffler, too, the two-stroke pop-pop being pleasantly muted.

The air cleaner is under the seat, with a Spanish-made 27mm Amal carburetor carrying fuel into the engine. A previous owner of this bike has replaced the Amal with a Mikuni. Should there be a need to remove the carb, the manual says, “Have in mind that you must shut the entrance of the admission pipe while the carburetor is out, in order to avoid the entrance of odd objects in the interior of the cylinder.”

1977 Montesa Cota 247-TPrimary drive is via spur gears, 22 teeth off the crankshaft, 64 teeth on the clutch, which uses “multiple steel discs in oil bath with constant tension springs….” That power goes through a five-speed transmission to a 10-tooth countershaft sprocket and a 40-toother on the back wheel. A very nifty chain-oiler has been built into the right arm of the swingarm, which holds a supply of oil that drips onto the chain just as it enters a tensioning device.

The engine/transmission unit sits in a tubular steel frame, with bolts holding it steady fore, aft and top. A single tube comes down from the reinforced steering head, spreading into a cradle at the front of the crankcase, with a sturdy skid plate built in. A small hole in the skid plate allows access to the drain plug. The rear section, holding the seat and upper shock absorber mounts, is built into the main frame, with a strong pivot point for the swingarm. The shocks on this model have no identification mark, but are probably of Telesco making. The telescoping fork is Montesa-made, with a 29.5-degree rake, 5.6 inches of trail.

A 21-inch wheel at the front wears a 2.75 tire, an 18-incher at the back has a 4.00 tire. Small 110mm single-leading-shoe full-width drum brakes are at both ends. When inspecting the wheels it is advisable “to slightly grease all the whirling points with SAE-40 oil.” A short 51.5 inches lie between the axles.

1977 Montesa Cota 247-TThe bike has an attractively slim look, having a narrow 2.14-gallon fiberglass gas tank with wings extending under the long saddle. Fenders are lightweight alloy. A small headlight, horn and taillight make it more or less roadworthy, except there is no battery. The speedometer is missing from the photo model. A modest toolkit fits into a cylindrical container beneath the seat. Dry weight, according to the manual, is 200 pounds…lightweight fun!

The last 247cc 247-T was built in 1977, the similarly branded 1978 version having a slightly smaller 237cc engine. That model was then dropped, but the 348-T version kept on for two more years.

Postscript: In 1980 a trials version, the Cota 348, won the World Trials Championship, but Montesa was running into serious financial difficulties. The next year Honda essentially bought the company in order to have better access to the European market, and Montesa Cota models are still being built–albeit with four-stroke engines.

Source: RiderMagazine.com

Retrospective: 1980-1984 Benelli 254

Benelli 254
1982 Benelli 254. Owner: John Goldman, San Francisco, California.

Here was a delicious little machine, a transversely mounted 231cc in-line four, putting out some impressive horsepower and weighing, fully fueled, a modest 269 pounds. With a top speed of more than 90 mph. However, in 1980 Benelli dealers also had 500 and 650 fours, along with an impressive six-cylinder 750, on the showroom floor…and Americans interested in Italian motorcycles did not care for these tiddlers. Anyone wanting a 250 could get one much cheaper from a Japanese dealer.

Cosmopolitan Motors was importing Benellis, and in 1980 the factory apparently told Cosmo that in order to get a few 750s they would have to take some 250s as well; Cosmo did so. Actually, when this 250 was conceived it was aimed strictly at the European market, as Italy and some other countries gave sub-250 bikes a good tax break and insurance costs were lower. The American market had never been seriously considered, but when 250 sales in Italy and elsewhere were not doing well, the company decided to foist a few off on the Yanks.

Benelli 254A little Benelli history: In 1911 the six Benelli brothers set up a garage in Pesaro, Italy, and specialized in fixing motorcycles—and soon started fabricating their own spare parts. In 1921 they built their first motorcycle, the 98cc Velo, and like any good Italian manufacturer took a big interest in racing. In 1937 they hired a young engineer named Lino Tonti in the racing department, and two years later he presented his 250 DOHC, in-line-four racebike, which was liquid-cooled and supercharged, ready for the 1940 season. Unfortunately Mussolini signed up with Hitler in June of 1940, and the rest is history.

War ended, Allied bombing had flattened the Benelli factory, but the boys—now older gents—got to work and had a pair of 250 and 500 single-cylinder street bikes for sale by 1947. When the GP races began again in 1949, they had a DOHC 250 single ready for the fray. In 1960 a new DOHC 250 four was at the track, winning a World Championship in 1969.

But the company was in financial trouble, due partially to racing expenses and the unexciting two-strokes they were selling to the public. Then a wealthy Argentinian businessman of Italian origin, Alejandro de Tomaso, showed up, acquiring 85 percent of the company in 1971 and then buying Moto Guzzi in 1973. Coincidentally, Lino Tonti was working for Guzzi at the time, and de Tomaso said he wanted some multi-cylinder bikes for the market. In 1974 the Benelli 500 and 650 fours appeared, which were closely patterned after some Japanese fours. But the next four-banger, the 250, was said to be very Italian, as nobody had made a road-going four that small. But it cost 30 percent more than Benelli’s 250 two-stroke twin.

Benelli 254The 231cc wet-sump engine was of the oversquare, short-stroke design, with a 44mm bore, 38mm stroke and a compression ratio of 10.5:1, happily revving to 10,500. All this was done using one overhead camshaft, two valves per cylinder and four 18mm Dell’Orto carburetors; 27 horsepower at the crankshaft. Ignition was done via battery and distributor, with the battery also powering the electric starter. Hardly necessary on such a small engine, but deemed essential in the modern market.

Primary drive was by a combination of chain and gears, a wet clutch putting power through a five-speed gearbox, with another chain going out to the rear wheel.

The open tubular frame was light, using the engine as a stressed member, and sportily rigid. A single downtube was bolted to the engine between the second and third cylinders. The front fork was a Benelli design, with the damping oil inside the cartridge, the oil in the fork legs for lubrication only. A pair of shock absorbers suspended the rear. The alloy wheels, both 18-inchers, had six twin-spokes, a 260mm disc brake on the front, drum at the back. Wheelbase was a modest 50 inches.

Benelli 254In 1977 similar models were sold by both Benelli and Moto Guzzi. With styling focusing on the sport rider, the Benelli was labeled the 250 Quattro; the Moto Guzzi 254 was aimed at the touring rider..

The styling fellow who did the Benelli bodywork had been charged with making the bike look modern, as well as appearing sleek. The end result was not very aesthetic; light thermoplastic panels, using straight rather then curved lines, covered the small gas tank and then angled down to where separate side panels would normally be. Moto Guzzi, on the other hand, had more traditional styling, with small panels making the gas tank look normal. Long panels traveled under the seat to a curved tail section, creating an attractively sporty look.

Benelli 254In an attempt to declutter the handlebar area on both bikes the speedo, tach and warning lights were positioned flat on top of the gas tank, requiring the rider to take his eyes off the road to see how fast he was going—not a good idea. Much better to have the instruments up by the headlight. For further decluttering, the reservoir for the front brake fluid was also tucked under the top of the tank.

Time went on, neither 250 selling well, and in 1980 the Mark II version came along. The Guzzi-labeled 250 was dropped, with the new Benelli 254 retaining the better-selling Guzzi styling and adding a little quarter fairing. The only picture we could find of the little Benelli sold in the U.S. was in the “1982 Motorcycle Buyer’s Guide” and it showed that slab-sided 250 Quattro model (the bike pictured in this article was imported to the U.S. from Europe). Cosmo dropped the model after 1982, while the factory went on producing the 254 version in Europe for another two years.

Benelli 254

Source: RiderMagazine.com

Retrospective: 1973-1975 Suzuki GT250 Hustler

1975 Suzuki GT250M Hustler
1975 Suzuki GT250M Hustler. Owner: Chris Wesney, Templeton, California.

Back in the early ’70s Suzuki was looking into the inevitable future and concentrating on getting into the four-stroke market, while still making good money from its two-strokes. And the predecessors of this GT250 Hustler had helped a lot.

Its parallel twin engine, perfectly square at 54 x 54mm bore and stroke, had first seen the light of the showroom floor in 1965 as the X-6 Hustler, a 250 tiger, which astounded the American motorcycling mind with a 90-plus-mph top speed and six-speed transmission. The engine was a simple piston-port design, with new-fangled automatic oiling, and cylinders were aluminum with iron liners.

Move forward eight years, and the rather similar GT250 Hustler appears—but with Suzuki’s Ram Air System (RAS) bolted to the top of the engine. The rubber-mounted hood was first seen on the company’s 1972 triples, the GT380 Sebring and GT550 Indy, which was the beginning of the Grand Touring series. The approach was simple enough, with this rather angular shroud aiding the cooling of the triple’s middle cylinder, sending more air through the cooling fins.

On a parallel twin this was more problematic, but useful in keeping the noise down. Two-strokes from the ’60s were notoriously rackety, especially in warm-up mode, and prone to give out a ringing and pinging sound from the fins. Strips of heat-resistant rubber were used in the 250’s cylinder-head fins to reduce the noise. All very civilized.

1975 Suzuki GT250M HustlerRAS was also a sales gimmick, giving the previous T250 model a new look. The factory was claiming the GT twin developed 31 horses at 7,000 rpm, but “Cycle” magazine used a rear-wheel dyno to measure the 1973 model’s horsepower: 22 at 7,500 rpm. The same magazine got a mere 20 horses when testing the similar 1975 version. As the humorist types back then liked to say, Suzuki was measuring power at the top of the piston.

It is true that Suzuki with this GT version had knowingly cut back on the power. This was because a major effort had been made, wise or not, to give the touring rider a quieter ride. However, it took some bright light to take the 26mm Mikuni carburetors apart and measure the slides; they had been lengthened by 6mm, which meant that full throttle was an impossibility. Two-strokes made a lot of noise from the intakes, so Suzuki used the longer slides on the GT–hence the slightly quieter engine. When found out, Suzuki immediately switched to correctly sized slides.

A battery and coil supplied the sparks, and the battery was a mere five amp/hour. Americans were coming to accept the electric leg, but because of weight and costs, no such starter was on the GT250. The rider’s left leg provided the starting mechanism, not that pushing the left-side kickstarter was much of a problem.

1975 Suzuki GT250M HustlerThe engine was Suzuki solid, with the crankshaft running on three ball bearings, the one-piece connecting rods having needle bearings both top and bottom. Gasoline passed into the crankcase via that pair of Mikunis, while lubrication was done by the improved CCI (Crankcase Cylinder Injection) automatic-oiling arrangement. Just to make sure that the end bearings on the crankshaft were properly taken care of, they were pressure fed using CCI’s multipoint injection system. Compression ratio was an acceptable 7.5:1. The oil tank, part of the right side cover, held 2.8 pints and had a little window to alert the rider when oil was getting low.

Helical gears sent power rearward to a multi-disc wet clutch and then through the tranny, with its own oil supply. Sixth gear was very much an overdrive, which helped reduce noise at touring speeds.

1975 Suzuki GT250M HustlerFrame was a double cradle, with a major change from its T250 predecessor found under the four-gallon gas tank; instead of one large beam, there were now a trio of smaller tubes, strengthening the chassis and allowing for a more positive feel in the corners. The frame extended under the seat, so there was no bolt-on addition. Since this had touring pretensions, wheelbase was extended almost an inch to 52 inches for better high-speed stability.

The telescopic fork was adequate, as were the pair of adjustable shocks on the swingarm. Both wheels were 18-inchers, carrying a 3.00 tire on the front, 3.50 on the back. Front brake was a competent single disc, with a drum at the back that was activated hydraulically. Above the headlight were a speedo and tachometer. Wet weight was a hefty 350 pounds, 50 more than the original X-6.

The GT designation did not really live up to the bike’s touring abilities. As a solo bike, it was OK in the quarter-liter category, but with a passenger on board taking off from a stop was both a bit slow and noisy. If the engine was pulling less than four grand, a stall was quite possible, and quiet departures were not to be had. Plus the seat height of 31 inches meant a relatively tall rider was probable, leaving not much room for a passenger. The saddle was narrowed at the front, for those with challenging inseams, but not very comfortable for the rider when carrying a passenger.

1975 Suzuki GT250M HustlerIn the end the GT250 Hustler, now a pussycat, only lasted three years. The RAS was removed, and the bike became simply the GT250 for the next two years–with bigger fins in the head to aid in cooling. That Ram Air System apparently served mainly to slow things down.

This 1975 model seen in the photos, in Aztec Yellow, spent much of its life in boxes and was only recently put back together–the only thing missing being the left side cover, which comes from a different year.

Source: RiderMagazine.com