Honda Metropolitan CHF50 User Manual

CYLINDER HEAD/VALVES
CYLINDER COMPRESSION TEST
Warm up the engine to normal operating tempera- COMPRESSION GAUGE
Stop the engine and remove the spark plug cap and
spark plug.
Install a compression gauge into the spark plug
hole.
To avoid discharging
the battery, do not
operate the starter
motor for more
than 7 seconds.
Open the throttle all the way and crank the engine
with the starter until the gauge reading stops rising.
The maximum reading is usually reached within 4-
7 seconds.
COMPRESSION PRESSURE:
1,393 kPa (14.2 kg/cm
2
, 202 psi) at 1,500 rpm
Low compression can be caused by:
- Blown cylinder head gasket
- Improper valve adjustment
- Valve leakage
- Worn piston ring or cylinder
High compression can be caused by:
- Carbon deposits in the combustion chamber or
on piston head
CYLINDER HEAD COVER REMOVAL
Remove the fuel tank (page 5-28).
Disconnect the vacuum hose and air supply hose.
Remove the bolts and cylinder head cover.
Remove the O-rings from the cylinder head cover.
O-RINGS
8-6

Honda Metropolitan CHF50 Specifications

General

Engine Type	49cc liquid-cooled single-cylinder four-stroke
Ignition	CDI
Transmission	Automatic V-Matic belt drive
Rear Suspension	Single shock
Front Brake	Drum
Rear Brake	Drum
Front Tire	80/100-10
Rear Tire	80/100-10
Seat Height	28.3 inches
Fuel Capacity	1.3 gallons
Bore x Stroke	37.8mm x 44.0mm
Compression Ratio	12.0:1
Starter	Electric
Curb Weight	179 pounds