Gilera SMT 50 Manual page 53

ENGINE TECHNICAL DATA
Engine
Diameter per stroke
Cubic capacity
Compression ratio
Cooling
Lubrication
Fuel
Carburettor
Clutch
Main transmission
Inlet
Gearbox
Speeds
Single-cylinder 2 strokes of
aluminium with inner nickel coating
and silicon carbide.
39,86 X 40 mm
49 cm³
11.5 :1
With coolant
Thermal unit: With engine oil 2T
through pump and variable
capacity
Transmission: With oil-coated
gear for transmissions
Unleaded petrol
Dell'Orto PHVA-17.5 with manual
starter
Oil-coated multiple disk
At rectified gears. Ratio: 21/78
Reed direct on the crankcase
At 6 speeds with selector, fork and
distribution drum operated by
external control
First Speed 11/34
Second Speed 15/30
Third Speed 18/27
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