Today in Motorcycle History

Eagle Motor Manufacturing Co

Eagle motorcycles and cyclecars were produced in London in 1912 and 1913.

  • Early in 1912 the company announced an ambitious plan to produce a wide range of models. These included a 2hp lightweight with overhead inlet-valve, Druid forks and belt drive. This was to be followed by 3½ hp, 4hp and 8hp twins plus 2hp single-cylinder and 4hp V-twin ladies models. In the spring they added a 10hp V-twin with a double exhaust.
  • Unfortunately these grand plans over-extended the company and it soon collapsed.


THE engine of this machine, which we had the opportunity of seeing last week, is designed for sidecar and cyclecar work, and for these purposes it should be eminently suitable. It is made by the Eagle Motor Manufacturing Co., at Shepherd's Bush, who also make worm-driven back axles, three speed and reverse gear boxes, steering parts and clutches for cyclecars.

The size of the engine is 85 mm. bore by 88 mm. stroke, cubic capacity 998 c.c. The cylinders are unusually smooth castings. There is a system of double exhaust which allows the exhaust gases from each cylinder to pass under the exhaust valve of the other as well as down its own exhaust pipe to the rear. The cylinders are slightly offset and compression is fairly high. The inlet valve is of the mechanically operated overhead type. The plugs are placed in the centre of the cylinders, and the compression taps at the side where they are readily accessible. The magneto timing is independent.

The Benton and Stone method of lubrication is used combined with a sump at the bottom of the crank case. The small end has already been described in our columns. The gudgeon pin is keyed to the connecting rod and rocks in wide bearings attached to a disc which screws into the top of the piston and is then secured by means of a wedge bolt and nut. The machine is equipped with a Senspray carburetter.

The Motor Cycle April 25th, 1912. Page 459


SEVERAL new models are being placed on the market by the Eagle Motor Co., 1, Shepherd's Bush Road, W.

The accompanying illustration shows the first to be turned out a 2 h.p. light-weight 60 X 70 mm. The engine possesses several new features. The inlet valve, which is mechanically operated, works on the overhead system, while two exhaust ports are fitted so as to allow free exit for the exhaust gases and to avoid distortion of the valve on one side. The combustion head on this model is detachable. The most interesting feature in this and the other types of engines made by this firm is the patent gudgeon pin fixing, which is illustrated herewith.

Eagle 1912 Gudgeon Pin

The method of fixing the gudgeon pin.
A. Taper pin fitting into split portion.
B. Nut.
C. Gudgeon pin bearing.
D. End of screw, burred over to prevent nut coming off.
E. Thread for screwing into piston.

A brass disc on which the gudgeon pin bearings are cast is screwed into the piston, tight up against the underside of the top of the piston. A mica washer is placed on the top of the disc to act as an insulator. The disc is split, and near the outer end of the split a threaded taper pin is inserted. After the disc has been screwed home the pin is locked by means of a nut, the end being burred over to prevent the nut unscrewing. The taper pin expands the disc and renders it a rigid fixing in the piston. The gudgeon pin is a tight driving fit in the small end of the connecting rod, and the rod is, of course, threaded on the gudgeon pin before the disc is screwed into the piston. For this method it is claimed that the fixing is absolutely safe and the gudgeon pin has a large bearing surface.

Both sides of the crankshaft run on ball bearings. In the large models a special oil sump is provided in the bottom of the crank case, which allows the oil to be kept at a reasonably cool temperature. The magneto is carried in an aluminium case, and is driven by means of an enclosed chain. The frame has the top tube dropped at the rear, while Druid forks, front and belt rim brakes, and footrests are provided.

The lubrication is by crank case suction through an adjustable drip feed and an auxiliary hand pump. Brown and Barlow carburetters are fitted to all models.

Other types which will shortly be ready are a 3½ h.p. tourist single-cylinder 85 x 88 mm., a T.T. model with an engine of similar dimensions, a 4 h.p. twin 60 x 60 mm., and an 8 h.p. twin 85 x 88 mm., which may be had with either belt or chain drive.

Other specialities are a ladies' 2 h.p. single with slightly inclined engine and a 4 h.p. ladies' twin. To these a stand will be fitted which will allow the rider to remain at rest in traffic without the need of putting the feet to the ground. Another item which will be supplied to fit these models is a special quickly detachable sidecar, the frame of which is suspended on semi-elliptical springs. All models may be had with change-speed gears and foot starting.

It is interesting to note that the Eagle Motor Co specialise in all repairs to motor cycles.

The Motor Cycle January 25th 1912 p99

Sources: Graces Guide, The Motor Cycle

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