Yamaha XZ550RJ 1982 Owner's Manual page 209

IF
1 . Upper level
1. Nivel superior
2. Lower level 2. Niveau minimum 2. Nivel inferior
Replenishing the battery fluid
A poorly maintained battery will deteriorate
quickly. The battery fluid should be checked
at least once a month.
1. The level should be between the upper
and lower level marks. Use only distilled
water if refilling is necessary.
CAUTION:
Normal tap water contains minerals
which are harmful to a battery;
therefore, refill only with distilled water.
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