bike acting funny (battery/charging problem)

[Fruity]

hi guys, so i got a NEW agm battery, checked the voltage (13.5V), it was good. intstalled it, took it out for a ride and tried to start it again 2 days later it couldn't start again. checked the voltage, it has dropped to 7.2V. what's the problem? the immobilizer lights even came on and the speedometer needles went all funny when i turn it on and the LCD gave some funny temperature reading. something short circuited?

please offer some advice, i'm desperate. thanks.

[Buckethead]

What kind of bike?

How many miles?

What sort of mods?

These things are all very helpful to know.

[Fruity]

sorry, it an 04 monster s4r, termi slipons, PC USB, and like i said just got a new agm battery.

[ducpainter]

It sounds like there is a draw on the system.

First thing to do is recharge the battery then use an ammeter to see if there is a draw and what component is causing it.

[Howie]

It sounds like there is a draw on the system.

First thing to do is recharge the battery then use an ammeter to see if there is a draw and what component is causing it.

Or your charging system is out to lunch, and you were lucky to make it home.  As ducpainter said, first step is to recharge the battery and test for a draw.  You need to either take an ammeter with a milliamp scale and place it in series (between the negative battery post and the battery cable) with the battery or use an ammeter with an inductive pick up.  AFAIK, Ducati has no spec for draw, but a good any car spec is less than .5 amp.  More than that, start pulling fuses, one at a time, until the number drops.  That circuit is your problem.  Oh, do make sure the key is not in park position.  If there is no drain, start the bike and run at 3K RPM with a voltmeter across the battery.  You should see 13.5 - 14.5 volts.  If you see more or less, post back.

[erkishhorde]

While you're pulling fuses I would check the battery recharge fuse first. When my voltage regulator went kaput I blew that fuse and the bike died on my after about an hour and a half of riding.

[Fruity]

thanks guys. first let me get a hold of a multimeter. first of all i'm a real novice when it comes to electrics. i hope you guys can walk me thru this in diagnosing what the problem is. i've pulled out all the fuses and they looked ok, that much i've done. i'll try and get a multimeter today and see what kind of readings i get. cheers.

[Howie]

A cheapo Radio Shack digital high impedance meter is fine. 

[Fruity]

when i connected the negative battery terminal there were sparks, is  this an indication that there's a short somewhere? couldn't get it to start up coz the shop didn't charge up the battery enough the V measured at 11.5 so i have to take it back to the shop today as they were closed for the weekend. will post back.

[ducpainter]

With the key off there should be no 'load' sparks.

You connected positive first then negative...correct?

[Fruity]

yes, that's exactly what i did.

[Howie]

Assuming the key was off you have a BIG drain somewhere.  Are you sure the key is not in the park position?

[Fruity]

yes absolutely positive.

[Howie]

Get yourself a meter and start pulling fuses.  Actually, before that take a walk around the bike and make sure nothing is lit or making noise.  In your case, a test light will probably work since the draw seems to be large.  Place the test light between negative on the battery and the negative cable.  If the draw is big enough, the light will glow.  Pull fuses one by one until the light goes out.  This circuit is where the problem is.  From then on, it is a process of elimination  Put the fuse back in.  Disconnect each consumer on that circuit until the light goes out.  A wiring diagram is your friend.  When the problem is solved, bring the battery back and have it charged and load tested to make sure it is fit for service

[Fruity]

ok, got the battery charged up, installed it, HOWEVER, this time when i connected the negative terminal, there were no sparks  so i didn't bother pulling out all the fuses, should i do it anyway? what i did was run the bike at about 3000-4000 rpms and checked it with the multimeter but the voltage remained. it didn't even budge. so i figure could this be the alternator. i unplugged the socket, ran the bike again, and checked it with the multimeter (AC current) all 3 leads were within spec. could this be the rectifier/regulator then? did a search on the forum but can't seem to be able to find anything on checking the rectifier/. howie???

thanks