As with many others involved in the field of automotive design, Stevenson had little in the way of formal qualifications in this area, although he had completed one term of mechanical engineering at the Technische Hochschule Berlin.

[5] His design concept was for a very simple three-wheeled car with room for two people inside, it would have two wheels at the front for stability, and be driven by a small engine at the rear.

[6] Initial work on the project was carried out with funding from Peter Stein, the publisher of the Rhein-Zeitung, using a 350cc Horex Columbus engine and other proprietary components, but economic conditions at the time proved unworkable.

[8] Now recognised as a major advance in driving safety, this provides an inherent stabilising effect on slippery road surfaces or when brakes are applied unevenly to wheels on either side of the car.

Nicknamed "Flea", the prototype car made its official – if somewhat inauspicious – debut in the Rosenmontag carnival procession in Fulda, in March 1950.

With the air-cooled engine, heavy body and slow, walking pace of the procession, it was perhaps inevitable that the car would succumb to heat failure en route,[15] nevertheless, it was greeted enthusiastically by the press.

[10] The car underwent significant development, modification and changes in appearance throughout its production life, but generally was only referred to in advertising and contemporary publications as either the Fulda–Mobil or the Fuldamobil, without a specific designated model number or suffix.

Internal production records and some individual vehicle registration documents have been adopted subsequently and are now used by most modern reference works to allocate more specific model designations, but should not be seen as definitive.

Fabric car bodies were common in the 1920s, and in post-war Germany the scarcity of sheet steel, coupled with low manufacturing cost and light weight, briefly countered more negative factors such as an old-fashioned appearance and relatively poor durability.

[20] The issues with the bodywork design were resolved by adding a rounded nose to the car, whilst at the same time moving the windscreen closer to the driver and making it more upright.

Rather than soundly rectify any structural failings, the remedial work consisted of the fitting of additional gaskets beneath the cylinders, a bodge which offered a far from a permanent or professional solution, whilst at the same time producing a detrimental effect on the overall performance of the car.

[20] A more contemporary source indicates Baker & Pölling gearing up production to extend its range of Split-single engines at this time, used in the 125cc Express Radex motorcycle and manufactured at their Niedernhall factory.

Further, the plywood and fabric bodywork had been superseded by sheets of hammered aluminium,[30] giving the car a very distinctive look, which led to the nickname "Silver Flea".

[34] Around the same time, Werner Ritterbusch, a disabled war veteran, drove his Fuldamobil on a round trip of nearly 9,000 km (5,592 mi) from Oberzwehren in Kassel to Lapland and back.

Former Czech racing driver Georg Kremel, a Fuldamobil company representative, made a non-stop journey across some of the steepest roads in Europe, taking in the Grossglockner, Plöcken and finally the Katschberghöhe Alpine passes, the last of which included a 2 km, 32% ascent.

[41] Recent sources state that a prototype had been displayed earlier in July 1953,[42][43] which may have been at the Great Rationalization Exhibition that took place in Düsseldorf at that time and where the manufacturers of the Fuldamobil had been awarded a gold medal for their contribution to motorization for the people.

[49][47] The Fuldamobil was now Elektromaschinenbau Fulda's largest source of income,[50] and the Type N would remain in production for some time[40][51] with parts for a large number of cars held at the factory.

[52] The firm of Nordwestdeutscher Fahrzeugbau [de] (NWF) had been established in 1946 and built specialised bodywork for a variety of vehicles, including buses, ambulances and postal vans and operated in conjunction with the much larger company of Krauss-Maffei.

The NWF factory had worked on a series of prototypes of a road/rail bus, the Schienen-Straßen-Omnibus, and when the expected demand for further buses of this type proved to be lacking, were left with excess capacity to fill.

[53] At this same time, International interest in microcars had grown rapidly and had begun to attract serious investment from established companies such as Messerschmitt and Hans Glas.

[56] The deal for NWF to build the main bulk of the new model appears to mark the breaking point between Karl Schmitt and Norbert Stevenson.

[58] When he was approached by entrepreneur Romanus Müthing in the Spring of 1954 he quickly accepted the offer of a substantial commission to direct a team working on a redesign of the Pinguin (automobile) [de].

[59][55] NWF were at the time the second largest coachbuilding company in Germany[60] and were looking to diversify their output with the Fuldamobil, to the extent that it would form the bulk of their production at a factory in Lohne, which was due to open in 1955 and where they were hoping to employ as many as a 1000 workers.

[55] Despite the reduction in capacity, the power output[55] was identical to the Sachs 360cc engine whilst at the same time resolving the capacity-related driving-licence issue, previously mentioned, with a motor more powerful than the 175cc Sachs engine used in the Type N. Torque figures were substantially less than the 360cc motor however and Stevenson pointed out that this would substantially reduce the cars hill-climbing ability.

The Fulda factory would continue to produce the 360cc cars on a limited basis, principally supplying Switzerland and the Benelux countries,[63] but eventually only the 200cc version would be sold.

Towards the end of 1954, manufacture at NWF was suspended “to meet urgent orders from Ford”, during which time demand for the car was said to have continued, with production from Fulda fulfilling requirements.

Sales volume had been insufficient to keep up with production and cars quickly stockpiled and were sold back to Fulda to save payment on licensing fees.

[86] The chassis was redesigned[80] with the front suspension simplified to cut costs, although this also meant the loss of its negative scrub radius[85] and the rear hatch was replaced by a larger fixed window.

The S7 was longer and taller with bigger windows and smoother lines than previous cars, and the weight reduction of around 55 kg significantly improved both acceleration and fuel consumption.

Often the situation is further confused by direct exports of complete Fuldamobils from Fulda to the prospective licensees prior to and in the absence of the development of any localised production.