AJW Motorcycles :: History
Chapter 6

The Flying Fox

John Wheaton said that by the end of 1930 his two-strokes were selling quite well.  However, it was becoming obvious that they were not going to sell in the quantities he had hoped. The big twins were still selling steadily, but John knew they were not going to make his fortune; if he were going to expand his business he would have to do more. So once again he was considering designing a 500cc machine.

At about this time Rudge-Whitworth Co had decided to offer their very successful engines as proprietary articles under the name ‘The Python’. This engine was being sold at a very reasonable price and it also had a very good performance. Rudge had, in 1930, made a clean sweep of the Junior TT, along with first and second places in that year’s Senior race. He therefore decided that his new 500cc machine should have this engine and he designed his frame around it.

Because the 500cc market was so well catered for he spent a lot of time designing the new machine.  It was quite useless producing another unless there were some definite new features incorporated. It was also very important that the motor cycle should have a good appearance and performance. Performance meant speed, liveliness and thoroughly good road-holding qualities.

John had learned a lot about frame design through racing Big-Twins, so he put everything he had learned into the frame of this new model.  He also went to a lot of trouble to keep the overall weight down without skimping on the specification, or spoiling the machine’s good looks.

The new machine had quite a lot of distinguishing features common place today, but quite novel at the time. Mudguards were flared and well balanced, the petrol tank was streamlined and was fitted on its top with a device to catch the rain in wet weather and prevent it running all down the riders’ legs, The saddle height was low, the wheel base short and ground clearance adequate.  John was pleased with the design of his new machine.

The first A.J.W. Flying Foxes, a 350cc and a 500cc, were announced at the Olympia Motor Cycle Show in October 1930.

The December issue of The MOTOR CYCLE announced.

Something different  can usually be expected from the A.J.W. Motor Company. For 1931 it takes the form of two extremely compact Python engined machines, one a radial valve 350cc and the other a 499cc model.

Head Lug

Head Lug

In design the two machines are almost identical except for their engines. Perhaps the most interesting feature is the frame, which, although of simple construction, is not only unusual, but has the advantage that it should be particularly rigid, in all six tubes diverge from the steering head.  Two run in a straight line to the rear spindle, two, which form the lower tank rails, to the seat pillar tubes and two to the front engine plates.  These last mentioned tubes, which, unlike the others, are brazed and not bolted to the steering head lug, are set wide apart at the top and converge at the bottom. Thus, the arrangement of the front down tubes approximate to triangulation. A similar scheme is adopted with seat pillar tubes, but in this instance the tubes are designed to converge at the top and be set wide apart at the bottom.

The chain stays, as on the two-stroke frames introduced last year, are malleable iron channel section castings, and are extended forward to bolt on the rear of the crank case and form a mounting for the Python four-speed gear box.

Immediately above the gearbox is a bolt on channel section, which carries the magneto and the oil tank.  The latter is ingeniously combined with the steel tool bags, which are set between the chain stays and seat stays, and makes a simple type of partial enclosure. In the near side of this toolbag oil tank unit is a pocket for accommodating the battery, which is held in place by a metal strap.

Frame 1931 and 1932

1931/2 Frame

Coil ignition and electric lighting are both standard equipment, but if desired magneto instead of coil ignition can be obtained at £2 extra. The dynamo is mounted between the engine and the front down tube, and is driven by chain, while the coil for the coil ignition is set vertically in the channel section at the rear of the cylinder.

Well-valanced mudguards are fitted and that for the rear wheel is quickly detachable immediately behind the saddle.  Once the Tommy bar carrying the saddle springs has been withdrawn, the rear two thirds of the mudguard can be pulled away, while if desired the saddle can be pivoted round its nose and rested on the tank so that still easier access to the rear wheel is obtained.

Flying Fox 1931

1931 Flying Fox

Other features of these machines, which go by the names of ‘350 Flying Fox’ and ‘500 Flying Fox’, are a totally enclosed primary chain lubricated by crank case breather, Python dry sump oiling, Druid single spring forks, Amal carburettor, twist grip control, ‘clean’ handlebars, 26in x 3.25in   Dunlop tyres, 7in  brakes, Terry saddle and chromium plating. The prices of the machines, which are fully equipped, are £59 10s and £62 10s. respectively.   For the T T replica engine there is an extra charge.

Python 499cc engineThe 499cc Rudge Python is a nearly square engine having a bore and stroke of 85mm by 88mm giving a capacity of 499cc. Steel flywheels are used in the built   up crank shaft assembly, which runs on single roller bearings on the timing side, and large roller and ball bearings on the drive side, the crank case being substantially thickened to give rigidity at this point.

The cast iron cylinder barrel is secured to the crankcase by six studs, while five more retain the detachable cast iron cylinder head.

A two-ring aluminium alloy piston has a fully floating gudgeon pin bearing direct both on the piston and small end of the H section steel connecting rod. Bass end pads prevent the gudgeon pin from scoring the cylinder walls. Positively lubricated caged roller bearings are employed for the big-end. Two overhead solid inlet and two overhead hollow exhaust valves are used, each having duplex valve springs retained by split conical collars. The over head rockers on the standard 499cc engine are carried on roller bearings mounted in hardened rings inserted in pillars cast on the cylinder head and are operated by internal rockers, tappets and push rods totally enclosed in oil tight cases.

Tool Box ASMThe oil tank, tool cases and battery carrier are made together in one unit which not only presents an extremely neat appearance, but also gives a large capacity oil tank and two roomy tool cases. The battery being pocketed into the centre of the oil tank enables it to be placed in the ideal position where it is subject to the minimum of vibration and road shocks. At the same time, as it is enclosed in on three sides, it is well protected from any damage that may result from a fall. The battery is easily removed without the use of spanners and, as a further precaution, it is earthed to the machine by a steel spring in addition to the usual earth wire.

The front mud shields, seen above, fitted between the exhaust pipes and the frame serve to keep mud thrown up by the front wheel away from the rider’s feet and legs, the additional shields are also shown fitted between the chain stays and silencers to prevent mud splashing out from the rear wheel.

Clutch (below) and gear box are of Rudge Python manufacture. Four speeds are employed, either of wide or close ratio as specified. The hand controlled two plate clutch is extremely sweet in action and light in operation, and will stand continued slipping without burning out or other ill effects,  The wide ratio gear box gives the following ratios on the 350, 5.3 7.2 9.5 and 17.2 and on the 499, 4.5 6.2 8.0 14.6 and with the close ratios of 5.3 6.6 8.6 and 13.7 is obtained on the 350 models, and 4.5 5.5 7.2 and 11.3 on the 499.  Kick starter folds out of the way when not in use.

Python clutch

These new models are due to be in production early in the new year,

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John Wheaton now had a new agent to distribute his machines; Glanfield Lawrence (Motors) Ltd. 230 Tottenham Court Road  London. W 1.  They told John that they could sell all the machines that he could make.

“And they did”, said John.

The A.J.W. record book states that 175 Flying Foxes were built in 1931.

Only one 1931 Flying Fox is known to have survived at the time of writing and that is in the process of being restored in Finland.

 

 

 

 

 

 

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