Honda HHT31S Owner's Manual page 61

Model
Engine type
Displacement
Bore & stroke
Maximum output
Maximum torque
Ignition system
Spark plugs
Starting system
Fuel
Fuel tank capacity
Fuel consumption
Oil capacity
Carburetor type
Air cleaner
Idle speed
Ignition switch
Throttle control
OD
Frame pipe
Thickness
Type
Drive
Bushing
Ratio
Gear case
Type
Size
Engagement
Clutch
Drive
Type
Tuneup
ITEM
Spark plug gap
Valve clearance
(cold)
TECHNICAL & CONSUMER INFORMATION
HHT25S
GX25
4-stroke, overhead-cam, single-cylinder
1.5 cu in (25 cc)
1.4 x 1.0 in (35 x 26 mm)
1.1 hp (0.82 kW) at 7,000 rpm
•
0.8 ft-lbs (1.09 N m) at 5,000 rpm
NGK: CMR5H
Unleaded gasoline (86 octane or higher)
0.53 qt/16.9 fl.oz (0.50 )
0.61 lb/hph (370 g/kWh, 276 g/psh)
2.7 fl oz (80 cc)
Diaphragm type (overflow return) with fuel pump
Material
OD
Engagement
Material
Length
Intake:
HHT25S
Exhaust: 0.11 ± 0.02 mm
Intake:
HHT31S
Exhaust: 0.15 ± 0.02 mm
ENGINE
4-stroke, overhead-valve, single-cylinder
1.23 ft-lbs (1.64 N
Transistorized magneto
NGK: CR5HSB or DENSO: U16FSR-UB
Recoil
0.55 lb/hph (340 g/kWh, 250 g/psh)
Single element, semi-dry
3,100 ± 200 rpm
FRAME
HHT25S
Slide type
Two-motion trigger style
1.0 in (25.4 mm)
0.059 in (1.5 mm)
Flexible steel cable
0.25 in (6.3 mm)
0.20 in (5 mm) square drive both ends
57-1/2 inch (1460 mm)
1.24 (input shaft) : 1 (output shaft)
Ball bearings, helical cut gears, no shims required
2-1/8 inch
4,200 ± 200 rpm
Square female
Centrifugal
SPECIFICATION
0.024 - 0.028 in
(0.60 - 0.70 mm)
0.08 ± 0.02 mm
0.12 ± 0.02 mm
HHT31S
GX31
1.9 cu in (31 cc)
1.5 x 1.0 in (39 x 26 mm)
1.5 hp (1.1 kW) at 7,000 rpm
•
m) at 4,500 rpm
0.69 qt/22.0 fl oz (0.65 )
3.4 fl oz (100 cc)
HHT31S
Nylon
3-1/16 inch
MAINTENANCE
Refer to page 37
See your authorized
servicing Honda dealer
59