Power came from a 9 bhp, 174cc four-stroke, single cylinder engine, although the four-wheeled Type 154 had a 204cc motor.

The Heinkel featured coil spring suspension on all three wheels, rack and pinion steering and hydraulic brakes.

Following problems over alleged infringement of BMW patents, production ceased in Germany in 1958, but the cars were then built in Ireland by Dundalk Engineering.

These Heinkel-Irelands had 198cc engines, producing 10 bhp. Irish production stopped in late 1961, but the design was to have another lease of life, in the form of the Trojan 200 built at the Croydon firm's factory until the end of 1964.

Like the other bubbles, the Trojan was eventually overtaken by more sophisticated economy cars, including BMC's Mini.

What to check

THE bodywork - especially the floor should be closely examined for evidence of rust or bodged repairs. An original car will have a spare wheel well built into the floor pan, plus reinforcing ribs on the inner wings.

The outer wings and the lower section of the single door can also suffer from rust.

Check the engine and drivetrain for obvious ailments and bear in mind that depending on how it has been looked after

If the power unit fitted is approaching 30,000 miles of active service, an early overhaul may be on the cards.