Kawasaki FE120

The Kawasaki FE120 is a 124 cc (7.57 cu-in) single-cylinder air-cooled 4-stroke internal combustion small gasoline engine with horizontal shaft manufactured by Kawasaki Heavy Industries LTd., for general-purpose applications.

The FE120 engine has an OHV (overhead valve) design; cast iron cylinder liner; float type carburetor with fixed main jet; flywheel magneto transistor type ignition system; mechanical governor and recoil starter with automatic compression release (electric starter was available as an option). The engine uses dual-element air cleaner or oil bath type air cleaner as an option.

Сylinder bore is 60.0 mm (2.4 in) and the piston stroke is 44.0 mm (1.73 in), compression ratio rating is 8.5:1. The Kawasaki FE120 motor produced 4.1 PS (3 kW; 4.0 HP) at 3,600 rpm of horsepower and 7.6 Nm (0.78 kg·m; 5.61 ft·lb) at 2,800 rpm of torque. The FE120G – 1/2 cam gear reduction.

General information

Engine Specifications
Model	FE120D / FE120G
Type	4-stroke, OHV, single cylinder
Displacement	124 cm 3 (7.57 cu-in)
Max. horsepower	4.1 PS (3 KW; 4.0 HP) at 3,600 rpm
Max. torque (crank PTO)	7.6 Nm (0.78 kg·m; 5.61 ft·lb) ta 2,800 rpm
Carburetor	Float type with fixed main jet
Cooling system	Forced-air
Ignition system	Flywheel magneto transistor type
Lubricating system	Splash
Starting system	Recoil or electric starter
Stoping system	Ignition primary circuit ground
Fuel used	Unleaded gasoline (octane number 86 or higher)
Fuel tank capacity	2.5 L (0.66 US Gal, 0.55 Imp Gal.)
Fuel consumption	250 g/HPh
PTO shaft rotation	Counterclockwise (from PTO shaft side)

Dimensions and Weight

	Kawasaki FE120 D/G
Length	291 mm (11.5 in)
Width	349 mm (13.4 in)
Height	344 mm (19.5 in)
Dry weight	14.5 kg (32.0 lbs)

Cylinder Block and Head

Cylinder block
Compression ratio:	8.5:1
Bore x stroke:	60.0 x 44.0 mm (2.36 x 1.73 in)
Cylinder internal diameter (max):	60.067 mm (2.3648 in)
Number of piston rings (compression / oil):	2/1
Connecting rod big end diameter (max):	26.052 mm (1.0257 in)
Connecting rod small end diameter (max):	14.042 mm (0.5528 in)
Piston pin diameter (min):	13.975 mm (0.5502 in)
Side clearance (Top):	0.150 mm (0.0059 in)
Side clearance (Second):	0.120 mm (0.0047 in)
Piston ring end gap (Top):	1.000 mm (0.0390 in)
Piston ring end gap (Second):	1.000 mm (0.0390 in)
Piston ring end gap (Oil):	Visual Inspection
Piston ring thickness (Top):	1.420 mm (0.0560 in)
Piston ring thickness (Second):	1.420 mm (0.0560 in)
Crankshaft journal diameter (min):	19.930 mm (0.7846 in)
Crankshaft crankpin diameter (min):	25.944 mm (1.0214 in)
Cylinder head
Valve arrangement:	OHV (overhead valves)
Valves:	2
Valve steam diameter (INTAKE):	5.430 mm (0.2138 in)
Valve steam diameter (EXHAUST):	5.415 mm (0.2132 in)
Valve spring free length (INTAKE):	31.8 mm (1.2520 in)
Valve spring free length (EXHAUST):	31.8 mm (1.2520 in)
Camshaft journal diameter:	PTO side: 22.927 mm (0.9026 in) Flywheel side (FE120D): 22.927 mm (0.9026 in) Flywheel side (FE120G): 29.930 mm (1.1783 in)

Tightening torque specs

Tightening torque specs
Connecting rod bolt	12 Nm; 1.2 kg·m; 9 ft·lb
Cylinder head bolt	25 Nm; 2.5 kg·m; 17 ft·lb
Flywheel nut	64 Nm; 6.5 kg·m; 47 ft·lb
Rocker arm lock nut	7 Nm; 0.7 kg·m; 6 ft·lb
Crankcase cover	10 Nm; 1.0 kg·m; 7 ft·lb
Oil drain plug	32 Nm; 3.3 kg·m; 24 ft·lb
Spark plug	23 Nm; 2.3 kg·m; 17 ft·lb

Service Information

Engine
Maximum speed	4,000 ± 100 rpm
Idle speed	1,600 ± 150 rpm
Cylinder compression	3.0-4.0 kg/cm2 (42-57 psi) at 600 rpm
Valve clearance
Intake valve clearance	0.12 mm (0.0047 in)
Exhaust valve clearance	0.12 mm (0.0047 in)
Oil system
Oil type	4-stroke or an equivalent (SF, SG, SH, or SJ)
Recommended oil	SAE 10W-30
Oil capacity	0.6 L (0.63 US. qt, 0.53 Imp. qt.)
Ignition system
Spark plug	NGK: BP5ES
Spark plug gap	0.7-0.8 mm (0.028-0.031 in)
Ignition coil air gap	0.3 mm (0.012 in)