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Engine
STIHL single cylinder four-stroke 
engine with mixture lubrication
Ignition System 
Electronic magneto ignition
Fuel System 
All position diaphragm carburetor with 
integral fuel pump
Weight
Blades
Other Special Accessories
Contact your STIHL dealer for 
information regarding special 
accessories that may be available for 
your product.
Displacement: 1.73 cu. in. 
(28.4 cm
3
)
Bore: 1.5 in. (38 mm)
Stroke: 0.98 in. (25 mm)
Engine power to 
ISO 8893:
1.3 hp (0.95 kW) at 
7,000 rpm
Idle speed: 2,800 rpm
Cut-off speed 
(rated): 10,500 rpm
Max. output shaft 
speed (cutting 
blade): 8,500 rpm
Valve clearance:
Inlet valve: 0.004 in. (0.10 mm)
Exhaust valve: 0.004 in. (0.10 mm)
Spark plug (resistor 
type): Bosch USR 7 AC
Electrode gap: 0.02 in. (0.5 mm)
Fuel tank capacity: 17.9 fl.oz (0.50 L)
dry, with deflector 
and blade 13.7 lbs (6.2 kg)
Special Accessories
Length Thickness Marking
8in. 
(200 mm)
3/32 in. 
(2.4 mm)
4133 / 01
8in. 
(200 mm)
5/32 in. 
(3.8 mm)
4133 / 02