The Isetta is a city car (namely it is small, practical and thrifty on fuel consumption) produced by the Italian carmaker Iso of Bresso (Milan) between 1953 and 1956 and, under licence, by the German BMW between 1955 and 1962.
After World War II the Italian industrialist Renzo Rivolta (refrigeration plants, household appliances) spotted a gap in the market – a means of transport accessible to a large slice of a population drained and impoverished by the war but very anxious to start living, working and moving about again.
So he decided to venture into the automotive field. The project he set in motion targeted passenger convenience and comfort, in addition to extreme practicality and simplicity. He called in two aeronautical engineers: Ermenegildo Preti and Pierluigi Raggi. The general lines of the project were laid down by by Preti while the body was designed by Raggi. The first prototype giving a foretaste of the egg-shaped body, the motorbike-derived mechanicals, the single front-opening door, was presented in the summer of 1952.
At the beginning it had just three wheels, a solution later abandoned in favour of four, the rear of which were very close together to avoid having to fit a differential (which would have meant adding weight to and complicating the mechanicals). The engine was a single-cylinder two stroke with a capacity of 198 cc and delivering 8 hp which would be increased in the final model.
The vehicle was officially presented at the 1953 Turin Motor Show. The hinging of the steering wheel to the front door to make occupant access easier caused a great deal of surprised comment.
But it was the vehicle as a whole, so different from all the other micro-vehicles presented, but capable of a quite respectable speed of 85 kph, that caused all the surprise and consternation.
In fact the Isetta took its place on the leading edge both for the originality of its design and the rational layout of its mechanicals. In spite of its cut-down dimensions it remained a car to all intents and purposes, livable and handy. The expansive glazing “betrayed” Giovanni Michelotti’s contribution to the design. The canvas roof could be rolled up to transform the Isetta into an open-roof car.
In spite of the wonder aroused by the presentation, sales were below expectations, perhaps because its price was just a little less than the Fiat 500 “Topolino”. As early as the end of 1954, however, Renzo Rivolta managed to strike a licensed manufacturing agreement with the prestigious German maker BMW which would produce it between 1955 and 1962 with great success: in Germany it was the all-time biggest seller among single-cylinder engine cars (161,728 units).
The BMW 250, namely the German Isetta, retains all the ideas of the Iso but adds a small but effective heating system and sliding side windows. From the mechanical point of view, the novelties were to be found in the adoption of a four-stroke engine with a slightly higher capacity (245 cc) which explains the new name, and power output of 12 hp.
The success of the BMW 250 was two-fold: first it was the perfect vehicle for people who could afford a second car, and it became the ideal vehicle to underpin the mass motorisation process. In Germany there was a special driving licence for vehicles under 50 cc.
BMW 300 1955
Single cylinder four-stroke engine
Capacity 297 cc
Power output 13 hp at 5200 rpm
Weight 350 kg
