The story begins with veteran riders Vaclav Stanislav and Jaroslav Simandl returning from the 1949 ISDT held in Great Britain who discussed improving the JAP engine which resulted in Simandl creating eight modified versions of the JAP design using the remnants of the Joli production.
He then designed a new short stroke engine which built in his workshop with 18 employees and was fitted to road racer which his son Jiri began racing.
The firm Simandl established went on to build speedway, ice-racing, moto-cross and road-going motorcycles with OHV engines of 250cc to 500cc. Early in the 1960s production was devoted entirely to speedway machines, and this factory was taken over by Jawa in 1969. Production of the speedway bikes continued but under the Jawa name.
ESO Production 1948 - 1964.
1949-1953 Production of tools, ingot moulds, presses etc. Speedway Engines "S" - small series.
1951-1957 Production of prototype for Road Racing Motorcycles.
1953-1954 Production of prototype Speedway Motorcycles "ESO" S-45
1953-1954 Scooter "ESO" 100 Production.
1953-1956 Carburetters "ESO" 30mm - 40mm.
1954-1956 Four Valve Racing Engine.
1954-1955 Spare parts for Road Race motorcycles Walters
1954-1962 Production Motocross Motorcycle "ESO" MC350
1954-1958 Formula 3 Race Car "ESO" F3
1955-1958 Production of Speedway Motorcycle "ESO" S-45
1955-1962 Production Motocross Motorcycle "ESO" MC500
1955-1962 Production Motocross Motorcycle "ESO" MC250
1955-1958 Prototypes of Road Race Motorcycles "ESO" 350 and 500 with OHC engines
1959-1965 Production of Speedway Motorcycle "ESO" DT-5
1959-1962 Prototype of Longtrack motorcycle.
1960-1962 Prototype of Motocross motorcycle "ESO" MC250 with desmodromic engine.
1962 Prototype of Motocross motorcycle with Longstroke Engine.
1963-1965 Production of Motocross motorcycle "ESO" MC500 with Long stroke engine.
1964-1965 Prototype of Ice Racing speedway motorcycle.