Mauser Einspurauto

Mauser, of Oberndorf am Neckar, made rifles. After the First World War it looked for other things to make: cars, and from 1920 measuring tools.source 1 A familiar story says that the arms makers turned to vehicles because the peace treaty banned them from making arms; the sources read for this page do not tie the Einspurauto to any ban, only to a firm finding new work after the war.

The idea was not new. Single-track cars with outrigger wheels had been tried before 1914: Kent’s Pacemaker, the Rabe-Mobil and Scripps-Booth’s Bi-Autogo.source 2 In 1920 Gustav Winkler of Berlin built a prototype of his own, and Mauser took it up and improved it; one source names a different Berlin designer, Reinhold Böhm.source 1source 3source 2 As the Mauser Einspurauto 2/6 PS, the “single-track car” was shown at the Berlin motor show in 1921.source 1source 2 A Motor Sport correspondent wrote in 1976 that it was exhibited at the Berlin show of 1926, perhaps a later appearance, perhaps a slip.source 4

A motorcycle in a car’s clothes

The body was a long, narrow tub of plywood covered in leathercloth, with one door on the left, a full-width windscreen fixed to the steering, and a rear panel that lifted off for maintenance. Two people sat one behind the other.source 3 Underneath was a pressed-steel box frame with forks front and rear, like a motorcycle’s. The front wheel steered and the rear wheel was driven by chain from a water-cooled single-cylinder engine of about 500 cc under the rear seat; the radiator sat in the nose, joined to the engine by long hoses.source 1source 3source 4 The engine started with a kick, and its three-speed gearbox lived in the crankcase.source 3

The driver steered with a wheel and worked car pedals for the clutch, brake and accelerator, but balanced the thing like a motorcycle.source 1 The two small outrigger wheels were the trick. Lowered, they held the car upright at a standstill; on the move, a lever raised them out of the way. The driver had to remember to let them down before stopping and to raise them again on moving off.source 1source 3source 2 The handbook asked for every moving part to be greased, and the radiator topped up, every 300 km.source 1 The maker gave the top speed as 60 km/h (37 mph).source 1

Series production ran at Oberndorf from 1923 to 1925, with a few more cars until 1927.source 1source 2 German Wikipedia puts the total at about 100 to 150, and the same encyclopaedia’s article on single-track cars calls Mauser the most successful maker of them.source 1source 2 Over those years the engine grew: 496 cc at first, then 510 cc, and on late cars 573 cc with overhead valves. The sources disagree about the details and about the power, which is given as 6 PS and as 10 PS.source 1source 3 Mauser built a conventional four-cylinder car alongside it, the 6/24 PS Typ M 6 of 1923–⁠26 and the M 7 of 1926–⁠27.source 1 It is counted among the German cyclecars of the 1920s, though it ran on two wheels.source 2

Winkler carries on

When Mauser stopped, in 1926 or 1927, Gustav Winkler bought the remaining parts and went on building the car himself, first in part of the Mauser factory and later in Berlin. He cut 12 cm from the wheelbase and lowered the car by 10 cm to make it handle better, and called it the Typ EA 2.source 3 It took either a 510 cc single or a BMW flat twin of 493 cc. Winkler production ended in 1929.source 1source 3

The French Monotrace

France had its own version, built from 1924 to 1930. The Ateliers du Rond Point in Saint-Étienne began it, and from 1926 Établissements Monotrace SA of Courbevoie, under Joseph-August Roten, built it on the Mauser pattern, with a 510 cc water-cooled single of about 12 hp, three speeds and chain drive.source 5 The sources call it licensed or copied; either way it is one of the cars on our page about cars built under licence.source 2source 5 At the Paris Salon of October 1925 it cost 8,900 francs, and a delivery van followed in 1926 and a single-seat sports model in 1929.source 5 A reader of Motor Sport who had a photograph of the German car compared the two in 1976:

in all other respects the Einspurauto, of which I have a photograph, was identical to the Monotrace Type Luxe

Others tried the idea too. In Berlin the Atlantic Einspurwagen, a separate make with a BMW flat twin, was built in about 100 examples in 1921–⁠22; later came the Whitwood Monocar of Portsmouth, of which six were built in 1934–⁠36, the Czechoslovak Dálnik of 1936–⁠42 and, in 1984, the Peraves Ecomobile.source 2

Oberndorf’s local history museum, the Heimatmuseum, has an Einspurauto, and one was shown in 1998 at the Deutsches Automuseum at Schloss Langenburg.source 3 In 1977 the East German magazine Kraftfahrzeugtechnik tested a survivor’s exhaust, in an article titled Abgasgünstiger Veteran, a low-emission veteran.source 1 No count of the survivors and no auction result has been found. Of the pictures on this page, the hero and the two Berlin photographs of 1923 show Mauser-built cars; the rest show Monotraces and Winkler’s car.