Yamaha Raptor 90 YFM90RA 2011 Service Manual page 90

CHECKING AND CHARGING THE BATTERY
Relationship between the open-circuit voltage
and the charging time at 20 °C (68 °F)
Charging time (hours)
These values vary with the temperature, the condition of
the battery plates, and the electrolyte level.
TIP
Since VRLA (Valve Regulated Lead Acid)
batteries are sealed, it is not possible to check
the charge state of the battery by measuring
the specific gravity of the electrolyte. Therefore,
the charge of the battery has to be checked by
measuring the voltage at the battery terminals.
1. Remove:
• seat
• battery band
Refer to "SEAT, FENDERS AND FUEL
TANK".
2. Disconnect:
• battery leads
(from the battery terminals)
NOTICE
First, disconnect the negative battery lead
, and then the positive battery lead
3. Remove:
• battery
4. Check:
• battery charge
a. Connect a pocket tester to the battery ter-
minals.
Positive tester probe →
Negative tester probe →
TIP
•The charge state of an VRLA (Valve Regulated
Lead Acid) battery can be checked by measur-
ing its open-circuit voltage (i.e., the voltage
when the positive terminal is disconnected).
• No charging is necessary when the open-cir-
cuit voltage equals or exceeds 12.8 V.
b. Check the charge of the battery, as shown
in the charts and the following example.
3 - 38
CHK
ADJ
positive battery terminal
negative battery terminal
.