Economic Motorcycles

Today in Motorcycle History

Economic Motorcycles


The Eynsford Engineering Co., Ltd., Primrose Works, Eynsford, Kent.

Produced motorcycles and three-wheelers from 1921 to 1923.

The engine was built in the United States as the Johnson Motor Wheel, and had been used to power a World War I trench pump. It was an interesting 165cc flat-twin two-stroke and the crankcase was split on the centre line with each half cast in one with a cylinder. It cost just 28 pounds.

Surplus engines were available after the war, and Economic installed these firstly in-line and then across the frame. It had friction driven transmission.

It was not marketed for long, although the reasons for this are unclear. It may have been because the engine was not reliable, or perhaps because of lack of supplies.

The engine was supplied by Economic to other manufacturers including Cambro and Mohawk, and may also have been sold as a stationary engine for industrial applications.

In the USA, the Johnson engine evolved into the Johnson outboard engine in 1921.

Three Wheelers

The firms' first three-wheelers were built in 1921 with an open two seater body of aluminium supported by a wooden chassis built of ash. It was powered by the same flat twin engine as used by their motorcycles, with chain drive to just one of the rear wheels. It had no suspension. Production ceased in 1922.

1921 165cc Economic Motorcycle

An ultra lightweight engined with a flat twin two-stroke - the Economic.


Economic Motors specialise in a two-stroke flat twin motor attachment with flywheel magneto, originally designed to be used as a pedal cycle attachment, but this unit, which is now British-made, will be shown fitted to a duplex frame lightweight with chain-cum-belt drive. An Economic de luxe attachment engine will also form part of the exhibit, and will be fitted to a pedal bicycle. It will incorporate the Economic spring drive and lighting from the flywheel magneto. The spring drive is bolted to the rim of the rear wheel, and the initial shocks are taken up by means of suitably arranged springs interposed between the sprocket and its attaclmient. The standard product of this firm will be a pedal cycle fitted with the unit, having a sprocket attached directly to the spokes of the rear wheel. A tradesman's carrier will be shown fitted with the Economic unit and spring drive to the rear wheel. Quite a novelty will be a simple three-wheeler for one person, fitted with the Economic engine and a friction gear.

The Motor Cycle, 1921

The 1922 Olympia Show.

ECONOMIC. (Stand 45.)

Friction-driven Miniature.

2 H.P. Model.

52.5x38.5 mm. (165 c.c); flat twin cyl. two-stroke; petroil lubrication; own make carb.; flywheel mag.; variable-sp. gear; no clutch or kick-starter; friction and beltdrive; 26 x 2¼in. tyres. Price £28 17s.

The Eynsford Engineering Co., Ltd., Primrose Works, Eynsford, Kent.

The Economic miniature has frankly been designed and built down to a price, but the fact that it has survived the handicap of a necessarily none too superfine external finish proves that it is quite a practicable vehicle. For next year this finish has been much improved, being now the more conventional black instead of red. It is notable as employing the only flat-twin two-stroke engine on the market, which incidentally is of the very simplest construction. The friction drive provides a wide range of gears, and also enables the overall weight of the machine to be kept down to 115 lb. This despite the fact that a duplex frame is employed. Its greatest achievement was an A.C.U. observed ride from London to Edinburgh at an average running speed of 17 m.p.h.

A light delivery model has a box carrier over the rear wheel.

Olympia Show 1922
The Motor Cycle, November 30th, 1922. Page 843

Sources: Graces Guide, The Motor Cycle,,

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