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Old 07-25-2011, 09:45 AM   #9 (permalink)
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
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Blackfly - '98 Geo Metro
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Battery pack woes!

So, four years of light use later, the battery pack in this bike has given up the ghost.

Power output from the motor is low, and the "fuel gauge" LED's on the twist throttle show "empty" under anything but the lightest amount of assist. Also, the charger will show "green" (charged) indicator almost immediately after plugging it in, which isn't normal.

As mentioned in post #3, the 24 volt battery pack is comprised of 2x 12v 12AH (@20H) valve regulated sealed lead acid batteries wired in series. They're the type of battery you'd see as backup in an alarm system, for example:

(The two batteries on the left are the same type of 12 Amp hour ones used in the bike's battery pack. The three on the right are 7 Ah.)

One of the pair is dead. The other still has about 2/3 of its rated capacity, after doing a simple capacity test using a 12v DC/AC inverter.
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