Slide out the rubber cap [A].

Starter Motor InstallationExhaust System Identification
Exhaust Pipe Mark Position [A]
Premuffler Chamber Mark Position [A]
Muffler Body Mark Position [A]
Premuffler Chamber [A] with Hole [B] for Oxygen Sensor [C]
Honeycomb Type Catalyst Position [A]
Specifications
...
Front Fender Removal
Remove:
Bolts [A] with Washers (Both Sides)
Reflectors (Both Sides, US, CA, CAL and AU Models)
Front Fender [B]
Take the brake hose off the clamp [C] (both sides).
Front Fender Installation
Apply a non-permanent locking agent to the front fender
mounting bolts.
Tighten:
...
Piston Removal
Remove:
Crankshaft (see Crankshaft Removal)
Remove the piston together with the connecting rod to the
cylinder head side.
NOTICE
Discard the connecting rod bolts and nuts. To prevent
damage to the crankpin surfaces, do not allow
the connecting rod bolts to bump against the
crankpins. ...