Motorcycle PMZ-A-750: history of creation, design, characteristics

PMZ-A-750 is the first heavy motorcycle in the Soviet Union, which was manufactured in the 1930s at the Podolsk Mechanical Plant. Produced in a double version, and with a stroller. Actively exploited in the army, the national economy, public services. At present it is of great interest for museums and private collectors.

Development

In the early 30-ies, the Scientific Automotive Tractor Institute (NATI) was asked to develop a heavy motorcycle with a capacity of 750 cm ³ , adapted to the road conditions of the USSR and suitable for work with a stroller. For the development of the project in Moscow was invited constructor Mozharov Piotr Vladimirovich, the creator of the first motorcycles IZH.

The working group reviewed the existing design solutions of the American firm Harley-Davidson and the German BMW, drawing a number of ideas. Invaluable help in the creation of PMZ-A-750 was provided by young designers Alexander Fyodorov, Igor Okunev, Sergey Semashko, Boris Fiterman and others. Later Fedorov worked as the chief engineer of the plant in Irbit. Okunev became the chief designer of the Moscow engine plant, and then the AZLK auto plant. Fitterman participated in the development of VMS cars.

From idea to realization

The concept of the engine, proposed by Soviet engineers, was reminiscent of "Harleevskaya", and was distinguished by many details. For example, the lubrication circulation system consisted of a dry crankcase system and a two-stage oil pump. The oil tank was proposed to be located in the overall casting of the motor housing. The motorcycle used a battery for ignition, the engine is equipped with a gear transmission.

First-born

Work on the future PMZ-A-750 was progressing very quickly. Drawings by the spring of 1932 were already prepared and sent to Izhevsk. In May 1933, four prototypes of motor vehicles were collected, called NATI-A-750. On August 20 of the same year they were taken to Moscow.

Compared with the standard models in the experimental motorcycles, the frame structure and the rear seats were simplified. On the left side of the front fork there was a sound signal, which was later transferred to the steering wheel. The shift lever and clutch pedal are located on the left side, as in American motorcycles of that period. Also in the American style the driver's seat is made: the saddle is deep, for the rear passenger is highly supplied. The footrests are far forward, the front and rear wheels are equipped with a retractable stand.

Production

The developers were eagerly awaiting the launch of mass production, but the shops in Izhevsk were not yet equipped enough to cope with such a complex product. In 1935, the People's Commissariat handed technical documentation to the operating Podolsky Mechanical Plant, which was a Russian branch of Singer. At the sewing machine factory, 11,000 employees worked and there were good conditions for responsible production.

The first serial motorcycle PMZ-750 came off the assembly line in 1935, exactly to the significant date - May 1. When production was visited by the People's Commissar of Heavy Industry Ordzhonikidze on July 25, the factory workers showed nine units of motor vehicles.

Specifications

Motorcycle PMZ-A-750 has the following characteristics:

• The cylinder of the motor is four-stroke, cooling is air. The working volume is 747 cm ³ .
• Power - 15 liters. from. (11 kW) at 3600 rpm.
• Number of gears - 3 (ratio 3,045-1,58-1,00).
• The transmission is a chain 5 / 8x3 / 8 ".
• The tire size is 4.50x19 ".
• Wheelbase - 1395 mm.
• The height of the model is 1050 mm.
• The length is 2085 mm.
• Clearance road - 112 mm.
• The total weight is 225 kg.
• Load-carrying capacity - 115 kg.
• The volume of the fuel tank is 21 liters.
• The speed (maximum) is 105 km / h (without the stroller).
• Fuel consumption (average) - 6 liters.

Reviews

Motorcyclists ambiguously evaluated the PMZ-750. Some praised the frame structure and easy access to the components, others considered the device not very well thought out. In many ways, the maintenance of the motorcycle was different from other models, which caused some inconvenience.

The mechanical gearbox was located at the top of the engine, while the shift was carried out by a special lever, located on the left side of the motorcycle. The clutch was of two types: either two-lever with a pedal on the left side, or a lever on the steering wheel on the left side. In the hot period, it was often necessary to change the oil in the lubrication system - every 1000 km. Customizing the motorcycle was difficult and time-consuming.

The Schebler carburettor often created problems when starting the engine. It required precise alignment of the optimum positions of the air damper, ignition (on the left side of the steering wheel) and the opening of the throttle (on the right side of the steering wheel). Motorcyclists jokingly deciphered the abbreviation PMZ as "try to get me started." Meanwhile, the design was innovative, many interesting ideas were used in subsequent models. In total, more than 4600 units were collected.

PMZ-750 was used not only in state agencies and the army, they were also sold to private individuals. A motorcycle with a stroller was especially appreciated . The price to the beginning of 1938 was 7760 rubles, it is very expensive in comparison with other mass models. For example, Izh-7 was sold for 3,300 rubles, "Red October" L-300 was estimated at 3,360 rubles.