Matchless G45 Replica Racing Motorcycle

The prototype of what would become the G45 first appeared at the '51 Manx Grand Prix ridden by Robin Sherry, eventually finishing 4th after a promising debut. In fact, the G45 was not an entirely new design but essentially a hybrid comprised of AJS 7R-based cycle parts and a tuned Matchless G9 roadster engine equipped with a new aluminium-alloy cylinder barrel and 'head.

In 1952 the prototype G45 garnered much valuable publicity, and not a little controversy, when Derek Farrant won the Senior Manx Grand Prix after leading from start to finish. Strictly speaking, a works prototype had no business in an event for amateurs riding over-the-counter machines, but AMC quickly announced that a production G45 would be available for 1953. Although still based on that of the G9, the production version's engine incorporated a different camshaft and breathed via a pair of Amal GP carburettors. Claimed power output was 48bhp, increasing on later models to 54 horsepower. Apart from revised valve gear and the eventual adoption of a forged crankshaft, the G45 changed little over the course of its life. Production ceased in 1957 after around 80 machines had been built, of which it is believed approximately half survive today.

The current private vendor purchased this G45 Replica from Bonhams' Stafford Sale in April 2016 (Lot 403). At that time we said the following: "This replica G45 has been constructed with a 7R frame and a 650cc Matchless G12 engine, in homage to the twin-cylinder racer. It is equipped with a Grimeca four-leading-shoe front brake, AMC clutch and four-speed gearbox, genuine 7R oil tank, and valanced alloy rims. Carburation is via twin Amal Concentrics, and ignition by Lucas magneto. It is fitted with an oil tap to prevent wet-sumping.

"Little is known of the history of the machine, other than that it was said to have been raced in Northern Ireland prior to acquisition by the vendor some three years ago. During the present ownership the bike has not been raced or paraded, although the owner has started it on regular occasions."

The vendor advises the 7R frame is a replica; the oil tank mentioned above was incorrect; and the Matchless G12 engine dates from 1959. The oil tank has since been replaced with a period-correct 7R (though possibly G45) item and repainted. The 7R type fuel tank is glassfibre, while other notable features other than those listed above include Suzuki GT380 front forks and a Manx-style Triumph conical rear hub/brake. The rear hub has been re-coated and the wheel rebuilt with stainless steel spokes and fitted with Manx style cooling rings. A rev counter drive gearbox has been sourced (missing when purchased) and the correct fuel tank supports fitted: steel brackets at the front, rubber bobbins at the rear.

The silencer stays have been replaced and the silencers upswept to better approximate those of a G45; the front wheel spacers corrected and the front mudguard fixing modified; the front fairing cowl repositioned; and a kickstart and cranked gear-shift fitted. It should be noted that the crankshaft breather has been blanked off and a pressure control valve (PCV) fitted to the breather routed from the dynamo area. The engine's state of tune for racing is not known.

Last run in June 2025, this splendid G45 replica provides the looks and style of the original at a fraction of the cost of the real thing.

Following a period of inactivity, this motorcycle will require recommissioning to a greater or lesser extent before returning to the track and thus is sold strictly as viewed. Prospective purchasers should satisfy themselves with regard to this motorcycle's completeness, history, authenticity, originality, usage, age and mechanical condition prior to bidding.

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