free website stats program need help | Page 4 | Harley Davidson Forums

need help

I'm betting on a Bad New Battery..

I had the same problem years back and when they FINALLY gave me another New battery, Installed and all was well....

Now IF it isn't kicking over this may be what Glider is suggesting by using the wires to start and by-pass the switch...

Keep us informed... that is how We (I) Learn..

signed....BUBBIE
 
getting all readings from battery post. bought the battery at the harley dealership. also had it load tested read full charge and 347 cold cranking amps.

There has to be something wrong with the tester the dealership used to test your battery. The reason I say that is because by definition, cold cranking amps (CCA) is the amount of current in amps that the battery will deliver for 30 seconds (at 0*F) and maintain 7.2 volts across the output posts. Now at 75*F it is probably more like 390 amps. But just for the sake of argument lets just say your battery has 347 CCA @ room temp.(And we know it should have EVEN MORE at ROOM TEMP)

So far do we agree? If so, continue.

So now we assume your battery was tested and is said to have 347 cold cranking amps. That would mean your battery can produce 347 amps for 30 seconds and maintain 7.20 volts across the battery posts.

So far do we agree? If so continue.

Then you agreed (entry point #26 paragraph 2) that the same fully charged battery will go from 12.70 volts to 3.80 volts when you hit the start (crank) button on the bike. So we can extropolate from the above statements and say with fairly good accuracy, that in order to pull the battery voltage from 12.70 to 3.8 volts in 5 seconds (or even less), your bikes electrical system would have to be able to load the battery to over 650 amps and that just can not be possible.

You could dead short a starter motor across the battery terminals and it would not draw that kind of current. Remember that this battery is only rated at 19 amp hour. These crazy amperage numbers are outside the physical limits of the battery.
 
Back
Top