something's draining my battery

When my battery is charged, the bike starts fine. After the bike sits for a few hours, the battery won't start the bike and I have to charge it up again. What could be causing this?

 

Bad battery, meaning won't hold a charge.

How old is the battery?

 

I bought the battery (online) and installed it for the first time in May. It's a Motobatt AGM, cost me $80 so I was hoping it was not the battery. It worked fine up until about a month ago when this problem started.

Is there a way to check to make sure it's the battery?

Also I should add that before this, the headlight fuse burned out, but I replaced it and a guy resoldered the fuse holder and fixed the connection to the headlight. Don't know if that would have anything to do with it.

 

Could be a bad (new) battery, a short that drains the battery or the alternator isn't charging enough.
Charge the battery and check the fuses and the connection that was soldered. Make sure the solder didn't drip and cause a short.
With the battery charged, check battery with voltmeter. Should read 12.5 to 13 volts, turn on ignition and push start button. If volts drop below 9 volts, most likely a bad battery. If it cranks, your volts should be 13 to 14 at about 2500 rpms. If not you have a charging problem.

 

Fully charge the battery and take it to the auto parts store and have it load tested.

If it's a higher capacity battery than originally fitted, it may not be being recharged fully by the bike and is now no longer capable of being fully charged.

 

A lot depends on how that Battery was filled and charged.

If you bought it on-line; it's likely a sealed battery.

If it's not a sealed battery; top-it-up with distilled water.
Fully charge the Battery with at least a 2-Amp Charger.
Bring the FULLY CHARGED Battery into an AutoZone Store.

Have the Battery TESTED for DEPTH of Charge.
CRANKING AMPS.

You might be operating off the TOP of that Battery.

ALSO;

TEST your CHARGING SYSTEM.
You should get a reading of +14.2 -to- +14.5VDC at the Positive Terminal of the Battery with the Engine RUNNING @ 2,000rpm's and above.
If not, ... you aren't charging the Battery while running.

 

OK
Assuming the battery is good and tests out OK.
How about hooking an amp gauge from the battery cable and the battery terminal. If there is an amp draw start unhooking things untill the draw goes away. As you disconnect things keep an eye on the meter, as soon as it goes to zero amp draw you found the problem.

MN

 

Depends on the TCI, if it draws amps like a car computer then that goes out the window unless it's ridiculously high.

 

As far as the battery capacity is concerned, I'm reasonably sure that won't be an issue due to the limit of space in the bike to battery size ratio. Even if it's a dry cell compact battery it would have to be a truck battery to be a strain on the bike.
Load test on the battery at a car part store is a good idea if you can find a clerk that knows how to do it properly. Make sure it's fully charged first.

 

Most digital multi meters like Fluke have a 10 amp setting. You can switch lead leads to the amp position and hook it up between the battery and the cable. If something is drawing an amp or two this will show up.

 

Amp meter not needed yet.

If you charge the battery and it starts the bike straight up but not 4 hours later it can only be one of two things.

Cactus battery or current drain.

Charge the battery, leave it disconnected for more than 4 hours then try it.

Wont start = dead battery
Will start = time to find the current drain (ammeter time)

 

Thanks everybody. I'll update after I try your suggestions.

 

The Ignition Switch is supposed to control the demand on the Battery.

Look for any Non-Factory wiring additions.
Some common ones are:
Alarms
Horns
Aux Lighting
Audio

 

I tested my battery. After a complete charge, the meter read 13.28. When I put it in the bike, no key, it read 12.24. When i turned the key to the on position, ignition to on position, it read 9.20.

 

That's really too high surface charge after charging...should only get to 12.85v or so...so that means you probably charged it too forcefully?...2 amps MAX on cycle batteries.

They won't usually throw enough ass to fire the plugs if they go below 9-10v when cranking, in my experience anyway.

If you had 9.2v with just the ignition on, I'd say the battery is toast.

Unless you've got a screamin' short to ground, which should blow a fuse or fry something. I don't see that as likely.

I think your AGM just bit the dust. Better check to make sure your reg/rec isn't allowing too much volts and frying it before putting a new one in though.

 

Occasionally you see a stator with a short to ground when the winding's insulation starts to get old and crack too.

IIRC you can check for this by checking for continuity between the engine case and the three leads going to the reg...if any show a path to ground, the stator is bad...and if there's any continuity between any of the three wires and any other of the the three, it's shorting out 2 phases of the windings...

Should show 1/3 of the total expected charging volts from any of the three when it's running...so if you expect to see 13.5v, each should show output of 4.5v.

Someone correct me if I'm wrong, it's been a while...

 

Thanks

The battery charger I have is a 12 volt, 1.3 amp charger. It's called batteryminder plus.

I got a new regular lead/acid battery from autozone today. I will charge it up in a bit and see if there's any difference.

 

Huh. Could be the AGM's top out higher than lead acid...haven't messed with em much.

But the other readings really point to trouble with that battery anyway...

I forget if you said...got warranty on that one? I do remember you said online sale? Prolly a bitch to warranty it out even if, huh?

Don't forget, check that charging voltage when you get the new one in there...make sure you're not cooking it or undercharging.

 

http://www.electrosport.com/media/pdf/f ... iagram.pdf

 

Wow thanks for all this help. This is really cool.

 

Does the xj chargng system not like agm batts? I was going to replace mine with an agm next season, but now hearing it only lasted a year in the bike, i dont think its worth the added cost.

thanks guys!

 

HOLD ON. 1.3A is about .1A too much. The MAX you should charge the new battery at is 1.2A; and I'd recommend 1.0A or even 0.75A to keep from cooking it. (Read the instructions, it says 1.2A, betcha.) If you're going to use the 1.3A charger, keep an eye on it and don't let it go more than about 10~12hrs max.

 

Not gonna argue with ya, because in absolutes you're right...but most people's charger has a minimum 2A setting, and it works fine for wet cycle batteries long as you don't do prolonged charging...

And in the case of a new one that needs to be filled, after soaking acid for an hour they will usually be at 85% charge or so, and only need 20-30 mins at 2A to top out. Sometimes not even that much.

My charger has a 0.3A maintain setting, but I don't even bother when putting a new one into service. But if you wanted to be absolutely sure of your procedure to a fault, a long charge at that rate would be the way to go. Me, I'm not that precise. Not in this case, anyway.

Or, if the bike starts fine and charges correctly, you can just use it from the surface charge after filling and soaking, and the bike's charging system will take care of the rest from there, provided you ride it far and fast enough initially to get it topped out.

This is not just my opinion, I have a good friend who has worked for 30+ years in the vehicle/equipment battery industry and he agrees.

Just didn't want you to think I'm stating uneducated opinion, for what it's worth.