Yamaha BIG BEAR YFM400S Owner's Manual page 148

1. Tail/brake light bulb holder
4. Remove the defective bulb from the bulb
holder by pushing it inward and turning it
counterclockwise.
1. Tail/brake light bulb holder
2. Bulb
5. Install a new bulb in the bulb holder by
pushing it inward and turning it clockwise.
6. Install the bulb holder (together with the
bulb).
7. Install the washers, and then install the
nuts.
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