Motorcycle production at Zschopau in Saxony began with DKW in the 1920s, and after World War II the works became East Germany's state motorcycle enterprise, later known as MZ. In the 1950s and 1960s engineer Walter Kaaden's work on expansion chambers extracted race-winning power from small two-strokes, influencing engine design worldwide as the technology spread.

MZ road bikes were known for toughness and simplicity: the ES touring singles, the TS dual-purpose machines and the ETZ 125 and 250 two-strokes that carried commuters across the Eastern bloc and were also exported to Western Europe. The company struggled after German reunification, and motorcycle production under the MZ name ended in 2008.

MZ manuals cover two-stroke engine rebuilds, crankshaft and piston specification, carburetor and ignition settings, clutch and five-speed gearbox service, and wiring diagrams for both six-volt and twelve-volt systems. Torque tables and clearances follow factory practice, the service schedules reflect the short maintenance intervals two-strokes require, and electrical fault charts cover the common ignition and lighting failures.

Surviving ETZs and TSs are prized as cheap, repairable classics whose owners do most work themselves. Restorers, rally riders and Eastern Bloc vehicle enthusiasts rely on accurate documentation for correct rebuilds, and on these machines a proper manual typically pays for itself during the first top-end service. Spares and pattern parts remain available, so documentation converts directly into kept bikes.