I have a battery that was purchased and installed in early March.  Since then, I have ridden 3000 miles.  I leave the bike unridden for two weeks and the battery is dead.  So I charge it for a few hours and it seems okay.  Bike starts fine.  I ride about 100 miles including one stop for gas after which the bike starts up okay.  One week later, the battery is dead again.         What's going on here?  Are motorcycle batteries this crappy, or do I have something else wrong?

Quote from: Toad Rider on June 18, 2007, 11:01:31 AM
I have a battery that was purchased and installed in early March.  Since then, I have ridden 3000 miles.  I leave the bike unridden for two weeks and the battery is dead.  So I charge it for a few hours and it seems okay.  Bike starts fine.  I ride about 100 miles including one stop for gas after which the bike starts up okay.  One week later, the battery is dead again.         What's going on here?  Are motorcycle batteries this crappy, or do I have something else wrong?

Something's drawing current with the bike switched off, probably.  Does the bike have an alarm or something?  If so, that would be the first suspect.  Otherwise, your alternator diodes could be leaking current in reverse, enough to discharge the batters over a period of a week.

To test: disconnect the battery + lead with the ignition off.  Then hook up a multimeter set to measure current (mA) between the disconnected + lead and + terminal.  Current flow should be nil to 5mA or so.  Anything greater and you have a leakage problem.

If this doesn't show any leakage current, you sure you didn't leave your key in the Park position, which leaves the taillight on?

-b.

Quote from: bosozoku on June 18, 2007, 11:09:53 AM

Quote from: Toad Rider on June 18, 2007, 11:01:31 AM
I have a battery that was purchased and installed in early March.  Since then, I have ridden 3000 miles.  I leave the bike unridden for two weeks and the battery is dead.  So I charge it for a few hours and it seems okay.  Bike starts fine.  I ride about 100 miles including one stop for gas after which the bike starts up okay.  One week later, the battery is dead again.         What's going on here?  Are motorcycle batteries this crappy, or do I have something else wrong?

Something's drawing current with the bike switched off, probably.  Does the bike have an alarm or something?  If so, that would be the first suspect.  Otherwise, your alternator diodes could be leaking current in reverse, enough to discharge the batters over a period of a week.

To test: disconnect the battery + lead with the ignition off.  Then hook up a multimeter set to measure current (mA) between the disconnected + lead and + terminal.  Current flow should be nil to 5mA or so.  Anything greater and you have a leakage problem.

If this doesn't show any leakage current, you sure you didn't leave your key in the Park position, which leaves the taillight on?

-b.

I 2nd that motion and move for a 10 minute recess,you're honor.To fix the problem.AAAHHHHH we're not in court are we? 

Yeah you probally have a drain on the bat as mentioned above, but make sure your water level is high enough. Mine seemed to need a little water added every few months. Don't know why and it seemed to work fine though.

If the alternator is bad, is it expensive/difficult to replace?

Quote from: Toad Rider on June 18, 2007, 11:47:09 AM
If the alternator is bad, is it expensive/difficult to replace?

Unlikely to be the alternator itself -- probably the diodes in the regulator if anything.  As far as expense/difficulty -- no and no.

-b.

If your alternator/generator is over charging,it will cause the water in the battery to boil off.That little battery can only take so much,that's why charging systems have regulators.

For my own knowledge as well as others here , if you were to take a meter to the battery terminals while the bike was running would it read around 14v like on a car ? I have to keep a battery tender on my bike , or else it'll start acting a little sluggish and the headlights will oscillate at low RPMs .

I need to check mine 'cause it seems as if it's not charging properly - the tender is just a quick fix in the meantime

Quote from: genEricStL on June 18, 2007, 12:48:52 PM
For my own knowledge as well as others here , if you were to take a meter to the battery terminals while the bike was running would it read around 14v like on a car ? I have to keep a battery tender on my bike , or else it'll start acting a little sluggish and the headlights will oscillate at low RPMs .

I need to check mine 'cause it seems as if it's not charging properly - the tender is just a quick fix in the meantime

But there great when you store for the winter.Use 1 on my riding mower.  Mower is 4 years old,never replaced a battery.However next year I'll have to cause Battery Tender is going on my GS for da winter.

If you're not keeping up the water levels, and 'tending' it while not in use, it will be worthless in a hurry.

I wouldn't blame the alternator immediately because of how you described your riding (very little).

Give a tender a shot. 

my 04 is starting to show its colors but my fault really i should have put that damn trickle charger on it last winter

Got 1 1/2 years on the OEM.  That was about 14,000 miles.
Got 3 1/2 years on the current battery and abou 11,000 miles.
Battery Tender is the trick.

To check the voltage regulator output...bike running, headlight on high, rpm's at 5000...voltage at battery should be 13.5-15
To check the stator...disconnect the 3 wires of the stator, bike running at 5000rpms, voltage across any 2 of the stator leads should be 75v or more.

Basically, running a bike under 5000rpms does very little to charge the battery.