Honda GX270 Technical Specifications

Engine Specifications
Model GX270
Type 4-stroke, OHV, single cylinder, inclined by 25°
Displacement 270 cm 3 (16.5 cu-in)
Max. horsepower 9.12 PS (9.0 HP, 6.7 kW) at 3600 rpm
Max. torque (crank PTO) 19.5 Nm (1.95 kg·m, 14 ft·lb)
Carburetor Horizontal type, butterfly valve
Cooling system Forced-air
Ignition system Transistorized magneto ignition
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 6.0 L (1.59 US gal, 1.32 lmp gal)
Fuel consumption 313 g/kWh (230 g/HPh, 0.51 lb/HPh)
PTO shaft rotation Counterclockwise (from PTO shaft side)
Type S Type Q Type L Type R Type H Type W Type P Type V
Length, mm (in) 355 (14.0) 380 (15.0) 405 (15.9) 440 (17.3) 425 (16.7) 370 (14.6) 380 (15.0) 400 (15.7)
Width, mm (in) 430 (16.9)
Height, mm (in) 410 (16.1)
Dry weight, kg (lb) 25 (55.1) 25 (55.1) 26.5 (58.4) 30 (66.1) 26.5 (58.4) 25 (55.1) 25 (55.1) 25 (55.1)
Operating
weight, kg (lb)
30 (66.1) 30 (66.1) 31.5 (69.4) 35 (77.2) 31.5 (69.4) 30 (66.1) 30 (66.1) 30 (66.1)
Cylinder block
Compression ratio: 8.2
Bore x Stroke 77 X 58 mm (3.0 x 2.3 in)
Sleeve internal diameter 77.00 mm (3.031 in)
Piston skirt outer diameter 76.985 mm (3.0309 in)
Number of piston rings (compression / oil): 2 / 1
Ring side clearance Top/second/oil 0.015-0.045 mm (0.0006-0.0018 in)
Ring end gap Top/second 0.2-0.4 mm (0.01-0.02 in)
Oil 0.2-0.7 m (0.01-0.03 in)
Ring width Top/second 2.0 mm (0.08 in)
Crankshaft outer diameter 32.985 mm (1.2986 in)
Cylinder Head
Warpage (limit) 0.10 mm (0.004 in)
Valve Arrangement: Overhead valve
Valves: 2
Stem outer diameter (standard): INTAKE 6.59 mm (0.259 in)
EXHAUST 6.55 mm (0.258 in)
Cam height: INTAKE 31.52-31.92 mm (1.241-1.257 in)
EXHAUST 31.56-31.96 mm (1.243-1.258 in)
Camshaft outer diameter: 15.984 mm (0.6293 in)
Engine
Maximum speed 3850 ± 150 rpm
Idle speed 1400 ± 150 rpm
Cylinder compression 6.0-8.5 kg/cm2 (85-151 psi) at 600 rpm
Valve clearance
Intake valve 0.15 ± 0.02 (0.006 ± 0.001)
Exhaust valve 0.20 ± 0.02 (0.008 ± 0.001)
Carburetor
Main jet Externally vented carburetor bowl: #88
Internally vented carburetor bowl: #95
Float height 13.2 mm (0.52 in)
Pilot screw opening 2
Oil system
Oil type Honda 4-stroke or an equivalent (SG.SF/CC.CD)
Recommended oil SAE 10W-30
Oil capacity 1.1 L (1.16 US gal, 0.97 lmp qt)
Ignition system
Ignition timing 20 ° B.T.D.C (Fixed)
Spark plug NGK: BP6ES, BPR6ES
NIPPONDENSO: W20EP-U, W20EPR-U
Spark plug gap 0.7-0.8 mm (0.028-0.031 in)
Spark plug cap 7.5-12.5 kΩ
Primary ignition coil resistance 0.8-1.0 kΩ
Secondary ignition coil resistance 5.9-7.1 kΩ
Ignition coil air gap 0.4 ± 0.2 (0.016 ± 0.008)
Starter motor
Brush length 7.2 mm (0.28 in) limit: 3.5 mm (0.14 in)
Mica depth 1.0 mm (0.04 in) limit: 0.2 mm (0.01 in)
Tightening torque specs
Connecting rod bolt (M8x1.25 Special) 14 Nm; 1.4 kg·m; 10 ft·lb
Cylinder head bolt (M10x1.25) 35 Nm; 3.5 kg·m; 25 ft·lb
Flywheel nut (M16x1.5 Special) 115 Nm; 11.5 kg·m; 83 ft·lb
Rocker arm pivot lock nut (M6x0.5) 10 Nm; 1.0 kg·m; 7 ft·lb
Rocker arm pivot bolt (M8x1.25 Special) 24 Nm; 2.4 kg·m; 17 ft·lb
Crankcase cover bolt (M8x1.25) 24 Nm; 2.4 kg·m; 17 ft·lb
Oil level switch joint nut (M10x1.25) 10 Nm; 1.0 kg·m; 7 ft·lb
Fuel filter joint nut (M10x1.25) 2 Nm; 0.2 kg·m; 1.4 ft·lb
Muffler mounting nut (M8x1.25) 24 Nm; 2.4 kg·m; 17 ft·lb
Air cleaner wing nut (M6x1.0) 9 Nm; 0.9 kg·m; 6.5 ft·lb
Oil drain bolt (M12x1.5) 23 Nm; 2.3 kg·m; 17 ft·lb
Fuel tank bolt (M8x1.25) 24 Nm; 2.4 kg·m; 17 ft·lb
Air cleaner mounting nut (M6x1.0) 10 Nm; 1.0 kg·m; 7 ft·lb
Fuel strainer cup (M24x1.0) 4 Nm; 0.4 kg·m; 2.9 ft·lb
Standard torque values
Bolt, nut (5 mm) 5.5 Nm; 0.55 kg·m; 4.0 ft·lb
Bolt, nut (6 mm) 10 Nm; 1.0 kg·m; 7 ft·lb
Bolt, nut (8 mm) 24 Nm; 2.4 kg·m; 17 ft·lb
Bolt, nut (10 mm) 37.5 Nm; 3.75 kg·m; 27 ft·lb
Bolt, nut (12 mm) 55 Nm; 5.5 kg·m; 40 ft·lb