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NSU Superfox 125cc OHC

NSU Superfox (Type 125 OSB)

Production: 1955-1957
Units built: 1955:4130 1956:9992 1957:1408
Engine: 1 cylinder 4-stroke, dry sump with external oil tank
HP: 8.8 at 6500 rpm
Engine displacement: 123cc
Cylinder diameter: 52mm
Piston stroke: 58mm
Compression ratio: 8.5:1
Ignition timing: 5 mm or 31 deg. before Top Dead Center (TDC) with mechanical advance device in full open position
Breaker points gap: 0.3-0.35 mm
Spark plug: W 240 T1, gap: 0.6-0.7 mm
Valve clearance (cold engine, piston at TDC, both valves closed): Intake valve: 0.05 mm, Exhaust valve: 0.08 mm
Valvetrain: OHC, hairpin-style valve springs, camshaft driven by ULTRAMAX rods,
Carburetor: BING 2/20/16 main jet:80, idle jet: 40 , needle jet: 2.68 , needle 2nd groove from top, idle screw 1.5 turns open
Transmission: 4 speed
Frame: solid NSU sheetmetal frame
Brakes: 140 mm drum brakes
Tire size: 2.75-19"
Weight: 132 kg
Max. weight: 290 kg
Length: 1987 mm
Gas tank volume: 10.8 ltr
Oil tank volume: 1.2 ltr, summer: SAE 20, winter: SAE10. Change oil every 2000 km and filter every 6000 km. After an oil change, let the engine idle long enough to pump the oil up into the oil tank before checking dipstick.
Fuel consumption: 2.7 ltr/100 km
Top speed: 95 km/h
General information: The Superfox has many features of the Supermax like the hi-tech engine . 1956: MICRONIC paper oil filter, 1957: new carb (Bing 2/20/18), 1958: new crankshaft design

By Hartmut Schouwer