Yamaha YBR 125K Owner's Manual page 69

1. Bulb
WARNING:
Avoid touching the glass part of the headlight bulb to
keep it free from oil, otherwise the transparency of
the glass, the life of the bulb and the luminous flux
will be adversely affected. If the headlight bulb gets
soiled, thoroughly clean it with a cloth moistened with
alcohol or lacquer thinner.
4. Put a new bulb, install the socket and the bulb rubber
cover.
5. Reconnect the connectors.
6. Reinstall the headlight assy. If it is necessary to adjust
the headlight beam, please consult a Yamaha dealer.
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