Post-War Contender

Story by Graham Clayton// Photos by Carl Kotevich and Graham Clayton
August 1 2015

Matchless enjoyed a long history, but unfortunately fell from grace along with the rest of the British motorcycle empire

In the early 1950s, lightweight 4-stroke singles were the preferred machines for trials riding and scrambling (the forerunner of motocross) in much of Europe. Prominent among these were the AMC (Associated Motor Cycles) Matchless 350 G3L models that had been produced in large volume for the British military during the Second World War, and which, painted in a gloss-black civilian colour scheme, were the first new motorcycles to be introduced in the U.K. market in 1945.

The following year, AMC introduced Britain’s first post-war competition model, the Matchless G3L C (for “competition”) scrambler. This was a long-stroke 348 cc OHV single with a 69 mm bore and a 93 mm stroke. The earliest versions had a 6.3:1 compression ratio and ran on low-octane pool gas fed by a one-inch 76D Amal carburetor, and transferred power to the gearbox using a four-plate wet clutch with fabric inserts.

The engines were of a pre-unit-construction design with a separate dry sump engine and a linked 4-speed gearbox. These machines were readily identifiable thanks to their tall alloy barrel and cylinder head with chromed exterior pushrod tubes on the right side of the engine. The G3L engines were fitted into a brazed steel-tube single-backbone cradle frame that was both hefty and strong.

Suspension Improvements

engine One of the standout features of the Matchless was its patented oil-damped telescopic front forks, which had first been introduced in 1941. These were a huge improvement over girder forks and provided an extra three inches of wheel travel, which made for a far more controllable ride. Matchless was also working on a rear suspension system in 1946, but it wasn’t introduced for another five years.

The Matchless 350 single was a rugged, reliable machine that used a 21-inch front wheel and a 19-inch rear, both laced with heavy-duty spokes. The trial-type Dunlops measured 2.75″ x 21″ on the front and a 4.00″ x 19″ on the rear.

Alloy fenders were used both front and back, along with 6.5-inch drum brakes and an upswept exhaust system. A three-gallon (13.5 L) steel fuel tank, solo twin-spring saddle and low-rise handlebars finished the package. Optional items included a headlight and rear brake light, making it both street legal and available for night use.
Matchless also produced a 500 class version of the G3L, designated the G80. It used a larger 82.5 mm bore along with the same 93 mm stroke for a swept volume of 497 cc, had a 6.0:1 compression ratio and used a heavier five-plate clutch.

Upgrading Continues

speedometer of bikeBetween 1946 and 1951, AMC continued to introduce various improvements to both scrambler models. In 1947, both versions were fitted with new, ½-inch shorter connecting rods, an improved oil pump and other modifications.

For 1948, new seven-inch drum brakes were made standard both front and rear on both models. The G3L C got a larger three-inch wide front tire, an improved four-bolt mount for the handlebars, and minor changes to the saddle and forks. Starting mid-year, the G3L C also began being fitted with the same heavier bottom end as the 500 G80 C.
Both models were up-rated in 1949 with cylinder heads that used larger cooling fins, hairpin valve springs and a new compression release. In addition, the introduction of a frame-mounted steel “bash plate” better protected the lower engine.

The following year, the 350 gained a five-spring clutch, a new alloy engine top end, an iron cylinder liner, cast-in valve seats, plus a Lucas “Wader” magneto. The fuel tank, now alloy, was downsized to 2.25 gallons (10.1 L) and was notably slimmer; a new cylindrical toolbox was now located under the saddle; and a quick-detachment headlight was fitted.

Rear Suspension Introduced

British motorcycle Rear suspension on Matchless singles was introduced in 1951, which comprised a rear swinging arm and twin shocks, the latter being the AMC-made large oil capacity “jampot units.” The rear-suspension versions of the 350 were designated as the G3L CS (for “suspension”), though the rigid-rear versions were still sold alongside them for riders who preferred a solid rear to use in trials competition. An alternative rigid-rear option was to replace the shocks and bolt in a pair of steel strut tubes in their place as needed.
All G3L Cs were by then equipped with a new Burman-type BA 4-speed gearbox, improved engine bearings and a relocated toolbox now on the right side of the machine.

From Basket Case to Beautiful Restoration

The 350 scrambler pictured with this article is Carl Kotevich’s award-winning 1952 Matchless G3L CS that he recently treated to a ground-up restoration after acquiring it disassembled from its original owner. This involved replacing quite a few old parts, including a variety of items that had found their way onto the bike from other brands. Carl got help in this regard from AMC Classic Spares in the U.K., as well as from AMOC (The AJS & Matchless Owners Club).

In 1952, AMC moved its Matchless scrambler’s magneto to the front of the engine, as had long been the practice with AMC’s very similar AJS scramblers, such as the model 16MC 350. Also new for the scrambler in 1952 was a Burman B52 gearbox. Other changes that year included the addition of an alloy backing plate for the seven-inch front brake and a new three-bolt handlebar clamp.

The engine for Carl’s bike was all apart when he bought it, so he entrusted the rebuild to well-known AMC-Norton guru Herb Becker in Kitchener, Ontario, to ensure that it was put together correctly. Herb replaced many of the engine’s internals to bring the 350 back to like-new full-spec condition. Also added, as part of the rebuild, was a brand-new gearbox sourced from AMC Classic Spares. Jim Struke, Herb’s AHRMA (American Historic Racing Motorcycle Association) partner, performed much of the engine reassembly work.

Ready for Competition

Carl’s bike is set up for competition use with a 9.5:1 compression ratio, high lift “SH” cam, a straight-through competition pipe, cast competition foot pegs that weigh a hefty 2.3 kg apiece, and a Lucas NR-1 competition magneto to supply the power to the single 14 mm spark plug. One non-stock item found on Carl’s scrambler is a 11/16-inch Amal 376 monobloc carburetor that replaced the standard one-inch Amal Type 76 AE-1AK.

Carl says the bike is generally easy to start using a set procedure, and with the aid of the valve lifter (compression release) while kicking down on the right side kick-starter. Once warm, the engine idles well and pulls away cleanly.

Imitating the Best

Carl’s Matchless rolls on competition-spec rims with a 19-inch front, as opposed to the standard 21-inch, plus a 19-inch rear. Onto these are mounted a pair of Ensign Universal Trials tires, three-inch front and four-inch rear. The rim size change (an early 1950s southern California off-road racing practice popularized by racing legend Bud Ekins) makes for better handling and control when riding in either deep sand or rough cross-country terrain.

Ekins began racing a Matchless scrambler in 1950, and had such success in U.S. events that he was offered a works ride by Matchless and became one of the first Americans to contest the FIM Motocross GP series in Europe.

On Carl’s 350, the original forks have been completely rebuilt with 11/8-inch fork tubes, and external but shrouded fork springs. Different lengths of fork springs can be used on the CS, allowing for different amounts of travel. The forks are also fitted with a wheel-type friction damper located on the upper triple clamp that can either loosen up or stiffen the steering.

The only instrumentation on the 350 is a Smiths speedo that reads to 90 mph (145 km/h). The 350 has a small solo saddle, the competition alloy fuel tank, alloy mudguards and a non-standard modest-rise handlebar. The machine has no electrics, just the competition magneto.

The overall weight of the 350 is about 145.5 kg dry; that’s some 27.3 kg lighter than its 350 G3LS road-going sibling. The engine develops an estimated 18 hp at 5600 rpm – good for about 100-plus km/h with its lower off-road gearing. Off-road bikes are more about low rpm pulling power or torque than high-revving horsepower. Carl says his bike has “a noticeable amount of torque while in second gear and a steady pull through third.”

Accurate Handling

Carl is still going through the breaking-in period for the rebuilt engine, so he hasn’t pushed it hard yet, particularly in fourth gear, but he reports that the bike “is very manageable because of its being relatively lightweight. The steering is accurate and the wider ‘Westerner’ handlebars add to the overall control and balance while riding,” Carl said. He also mentioned that using a heavier fork oil also helps dampen the front suspension, although the teledraulic forks manage nicely over most terrain. The combination of the massive jampot rear shocks and the heavier springs on the solo seat, working together with the swingarm itself, offers a strong positive grip. Braking is sufficient while riding at lower speeds with the help of the aggressive tires.

In the 1950s, the G3L C and CS models, and their AJS siblings were competitive mounts in off-road competition, including trials, scrambles, hillclimb and grass-track events, and consequently sold well. One of the best known of the many British Matchless 350-mounted competitors in the early 1950s was Artie Ratcliff, who won the gruelling Scottish Six Days Trial twice, first in 1950 and again in 1954. He and fellow Brit Matchless racer Ted Usher won numerous national-level events throughout the decade riding G3L competition machines.

For 1954, the Matchless 350 benefited from an enlarged inlet port and was fitted with a new 11/16-inch Amal carburetor. This was replaced in 1955 by an Amal Type 376 monobloc carb of the same intake size, and this is why Carl went the same route with his scrambler.

Unfortunately, 1954 was destined to be the final production year for rigid-rear framed Matchless models.

For 1956, AMC had developed new short-stroke all-alloy engines for its 348 and 497 cc competition models. The new bore-and-stroke dimensions were 72 x 85.5 mm for the 348 cc scramblers badged as either Matchless or AJS models. These bikes were built for several years, but were ultimately deemed to be both too heavy and too expensive to be competitive in the market for off-road performance machines.

Financial Troubles

Production of the G3L-based 350 Matchless scramblers ceased in 1960, though production of the larger-capacity Matchless G80 models continued until 1966. By then, AMC’s faltering bike sales and dire financial situation resulted in bankruptcy. That same year, AMC’s assets were purchased by Manganese Bronze Holdings and its Matchless-AJS operations were absorbed into the newly formed Norton-Villiers concern. This would mark the end of the line for Matchless and AJS singles production. “


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