AGM BATTERY PROBLEM.

engelwagen · Post by **engelwagen** » Wed Oct 08, 2014 11:47 pm

i PUT IN A MOTTTO AGM BATTERY FROM EBAY TODAY IN MY 64 CA77. THE BATTERY HAD A SURFACE CHARGE OF 12.5 V WHEN i GOT IT. I REPLACED THE OLD ROTTEN GROUND STRAP NEGATIVE LEAD WITH A HIGH END 8G COPPER STRAND WIRE. i WAS ABLE TO KICK THE BIKE OVER AND IT STARTED UP. THE NEUTRAL LIGHT DIDNT SEEM TO BRIGHT.I DROVE THE BIKE DOWN THE STREET AND ONLY MADE IT ABOUT 5 HOUSES AND IT DIED AND BATTERY WAS COMPLETELY FLAT. ZERO VOLTAGE ACROSS THE TERMINALS. i PUT A CHARGER ON IT WHILE IT WAS STILL HOOKED UP AND IT READ 12 VOLTS FROM THE CHARGER OUTPUT. i KICKED IT OVER AND HAD IT RUN FOR A FEW MINUTES AND TESTED THE VOLTAGE ACROSS THE TERMINALS WHILE IT WAS RUNNING AND CHARGER HOOKED UP AND IT SAID 29 VOLTS????WAS THAT BECAUSE THE CHARGER WAS HOOKED UP AND ON? I HAD NO ELECTRICAL PROBLEMS BEFORE I REPLACED THE BATTERY. NOW IT SEEMS THAT THE NEUTRAL LIGHT NO LONGER WORKS THOUGH ALL THE LAMPS STILL WORK.

G-Man · Post by **G-Man** » Thu Oct 09, 2014 3:10 am

Hi

Please could you write your posts in lower case as upper case is like shouting and hard to read...

We need to determine the source of your problem. Have you tried putting the old battery back in?

Stupid question. Is the battery connected up the right was round?

29 Volts would probably blow your bulbs. Inadvisable to run the engine with the charger on.

It sounds like there is a bad connection to the battery somewhere.

Is your new ground strap connected to bright metal on the chassis?

Does anything look / smell hot?

Send come pics and then we can see what you see...

G

Hamamatsu Nippon · Post by **Hamamatsu Nippon** » Thu Oct 09, 2014 12:00 pm

Be very careful working around an AGM battery. They don't like 15v, so at 29v I'm surprised the battery didn't go kablamo. You're getting some pretty odd numbers from your voltmeter. 0 volts? even a battery sitting in a bone yard for 5 years is going to show something. 29volts when running with a charger also seems hard to reach. Try using another voltmeter and compare the results.
I would remove the battery then check the terminal voltage. If it still shows 0 volts I wouldn't put a charger on it. If it shows voltage, use a low amperage smart charger until it clicks to float mode. Let the battery sit for several hours to see if it maintains its charge. Take a good look at the rectifier. Is it burned, are the wires secure/sealed?

engelwagen · Post by **engelwagen** » Thu Oct 09, 2014 1:44 pm

The battery has zero voltage. I am going to get a replacement. I wonder if the positive terminal shorted out against the battery over or if the battery was just defective. If either terminal touched the battery lid that would kill the battery I think. The bike worked great with the old battery.

G-Man · Post by **G-Man** » Thu Oct 09, 2014 2:27 pm

If it discharged from 12.5 volts to zero in such a short ride there's going to be some evidence, somewhere....

G

engelwagen · Post by **engelwagen** » Thu Oct 09, 2014 10:49 pm

I took the old battery and charged it up. it was sitting at 10.5 volts. I kicked the bike and started right up. I checked the voltage and it was 12.5 or so. When I revved it it jumped to 13.9 .I did not check it with the headlight on. I think the positive terminal grounded on battery cover and killed the battery or the battery was defective. I have a new agm coming under warranty. I will check voltage with new battery before I put cover on and check the clearance.All of my lamps are good except the neutral light. Are they hard to find and replace?

engelwagen · Post by **engelwagen** » Wed Oct 22, 2014 10:20 pm

The new replacement battery came in today. Everything seems to be fine. I have 12.99 volts across the battery while it idles and when I have the lights on no flicker or dimming and they battery output was a steady 12.99. Looks like the only lamp I lost was my neutral light. I have searched online and I cannot find a replacement.