Saxomat

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Transmission types
Manual Sequential manual Non-synchronous Automatic Tiptronic Semi-automatic Twin-clutch gearbox Direct-Shift Gearbox Saxomat Electrohydraulic manual transmission
Continuously variable Variomatic multitronic
Bicycle gearing Derailleur gears Hub gears
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Saxomat was a type of automatic clutch available as an option on Fiat 1800, Saab 9-3, Volkswagen Beetle, Borgward, Goliath, DKW, BMW, Opel, NSU, Glas, Trabant and Wartburg. Opel sold it as Olymat; Trabant and Wartburg named the system Hycomat. The Hydrak, used in some Mercedes-Benz vehicles between 1957 and 1961, was a similar system with a hydrostatic torque converter in place of the Saxomat's centrifugal clutch. The system also reappeared in the 1990s as Sensonic.

Cars with a Saxomat clutch did not have a clutch pedal. The Saxomat consisted of two independent systems, the centrifugal clutch and the servo clutch. The centrifugal clutch was engaged above certain engine RPM by centrifugal force, acting on spinning weights inside the clutch, similar to a centrifugal governor. The servo clutch used an electric switch that supplied vacuum via an actuator valve to a reservoir that disengaged the cluch. The clutch is disengaged automatically whenever the gear shift lever was touched.