Honda GL1800 2004 Owner's Manual page 128

Cylinder Head Side Cover Removal
Refer to Saf ety Precautions
Both cylinder head side covers must be removed for spark plug maintenance.
The left cylinder head side cover must be removed for crankcase breather
maintenance.
Removal
1. Remove the rubber plugs.
2. Remove the bolts.
Installation
Installation can be done in the reverse order of removal.
LEFT SIDE
cylinder head side cover
on page 106 .
bolt
Cover Removal
rubber plug
Servicing Your Honda
121