0.8 amp battery trouble

[HOOD66]

I am running a 1981 xs 650 with pamco ignition stock charging system kick only.

I tried using a small 0.8 amp battery. And am getting high voltage spikes over 14.5 volts resulting in blown headlamp and tail light. i decided to disconnect the small 0.8 amp battery and hooked up directly to my car battery. The voltage stays around 13.5 volts at a high rev with the car battery. I checked all grounds they are good.
has anyone had any trouble with this battery, What should i do. What battery would work on the cheap? Or am i missing something?

 

[XSLeo]

From the few people that report on using that battery they work well but don't last long.
How long have you been running that battery?
Leo

 

[HOOD66]

Just a few months bike just got finished. It does hold a charge bike starts every time.

 

[HOOD66]

A few pictures and the wiring diagram I used.

 

[jamesgs4]

14.5 shouldn't blow your headlight or taillight. Is your regulator mounted in open air?

 

[HOOD66]

I am getting voltage spikes over 14.5 highest I read was 15 volts. And the regulator is in the stock location.

 

[jamesgs4]

I used to run those without any problems, but I am beginning to think I was just lucky? I guess you are taking a chance with a 6 dollar battery.

 

[HOOD66]

Is there any reason why voltage is ok on the car battery and high on the .8 amp battery? FYI voltage tests were done with all lights off.

 

[coughing skunk]

I had one for almost a year with no issues, then one day the bike was breaking up in mid RPMs and wouldn't rev past it. I built my own 'super capacitor' to replace the battery and have been trouble free since.

PamcoPete suggested that the max charging current of the .8Ah battery is much less than the output of the charging system on the bike, causing over heating and internal shorting of the battery.

I think the real ticket would be the .8Ah battery with a capacitor bank in parallel to suck up the extra current. Still maintains a smaller than normal size battery package.

 

[XSLeo]

The output of the alternator is around the 14.5 volts as long as the reg/rec is working and the amps can be anywhere from just a few milliamps up to around three or four amps.
The .8 a/h battery can handle the low amps ok but it can't handle the higher amps. A car battery has the physical and electrical capacity to absorb this higher amps.
With the .8 amp battery not able to withstand this it may cause the voltage to vary.
I might try a bit larger battery. Say a 4 amp/hour battery. It will be bigger but it will handle the alternator output better.
Leo

 

[HOOD66]

I will try a bigger battery! thanks everyone for the info and i will post the results later this week.

 

[HOOD66]

I get a new battery today 12 volt 7amp. I am now producing 14.5 volts steady through out the RPM range. Again thanks for the help.