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Battery not charging

Roxter Rider

New member
The bike is a 2004 R1150R Rockster 20,000 miles and has ABS. The battery is not holding a charge. I put it on the trickle charger and it will take a full charge. I can stop to fuel up and it will restart but after a day(12 hrs) at work it will not start. I have replaced the battery and it is doing the same thing. I am guessing alternator possibly?
 
The only thing I have is heated grips. About three months ago I did have the left cylinder, valves and piston replaced but I don't see how that could cause this effect.
 
you need to do a few tests to be sure.

Check static battery voltage it should 12.6 volts or above

Check cranking voltage of the bike, it should be n o lower than 9.6 volts

Charging voltage should be 14+ volts engine running.

I think you will find less than 14 volts running which points to the alternator or belt.

David
 
you need to do a few tests to be sure.

Check static battery voltage it should 12.6 volts or above

Check cranking voltage of the bike, it should be n o lower than 9.6 volts

Charging voltage should be 14+ volts engine running.

I think you will find less than 14 volts running which points to the alternator or belt.

David

Good suggestions to make sure the charging system is functioning properly.

If you suspect a parasitic drain on the battery the easiest way to find out is to disconnect one of the battery terminals and place a voltmeter set on the DC Amperes setting in between the battery and the terminal you just disconnected and measure the current. If you have a clock on that bike you will see less than three milliamps (.003 Amps) of current draining the battery. If it is any more you have a problem somewhere that needs to be tracked down.

If the charging systems tests OK and the parasitic drain current tests OK remember that even a new battery may not be perfect and may be draining _itself_ due to dendrites or some other small short in the battery itself. Brand new defective batteries are rare but it does happen from time to time.

If you see the correct voltages as per the previous post and there is no significant current observed at the battery then suspect the battery itself as the problem.
 
Just curious- how old is the battery? It may be worth taking the battery to a local auto parts place (Autozone, etc.) and have it load tested. They usually will do it for free and that may save you some headache...
 
I am guessing alternator possibly?

Stop guessing and take measurements. Hook up a digital multimeter to your battery while the engine is running. Take the RPMs up to at least 2000 and see what it reads...hopefully between 14.0 to 14.4V.

You'd know for sure if you had a voltmeter installed.

015%20-%20Datel%20Meter%20-%20Mounted%202-L.jpg
 
Check static battery voltage it should 12.6 volts or above

Check cranking voltage of the bike, it should be n o lower than 9.6 volts

If it has the same OEM battery, rest voltage is 12.85 to 12.90 V for a healthy battery. Mine sits at 12.9 V and then drops down to 12.8 V three weeks later when parked for an extended period.

Cranking voltage is kind of hard to measure since the load varies.
 
If it has the same OEM battery, rest voltage is 12.85 to 12.90 V for a healthy battery. Mine sits at 12.9 V and then drops down to 12.8 V three weeks later when parked for an extended period.

Cranking voltage is kind of hard to measure since the load varies.

My meters have a "min/max" function. It remembers both. Its a fluke. :blah

The 12.6 volts static is a minimum for ALL batteries. Below that and the battery is not fully charged or defective.
That is why its the first test. If it fails that one then cranking test is kinda useless.

My R1200R has been sitting for a week since run, I will check it today. I use no charger of any kind.


David
 
My meters have a "min/max" function. It remembers both. Its a fluke. :blah

Yup, so does my Fluke 88V (same as the 87, but the automotive version with RPM instead of Hz), but I also have a scope and 200A current shunt to perform current draw tests. People buying a meter should look for that function. Its available on meters not costing all that much...well under $100.


The 12.6 volts static is a minimum for ALL batteries.

For a Flooded Lead Acid (FLA) battery, yes, but the AGMs and GELs sit at a higher voltage when fully charged. My OEM BMW battery rest voltage is 12.9V days after the charger had been disconnected.
 
Thanks for the info. I don't have a good digital meter only an old analog. I am going to talk to the instrument guy at work and see if I can borrow his multi-tester, I am not sure which fluke (he has several) he uses but he usually has a couple around I can "borrow" from work.
 
You assume in all this that the battery is OK, and think the problem might be a parasitic drain or a defect in the bike's charging system. You think the battery's OK because it'll take a charge then start the bike.

I think the most likely scenario is that the battery's defective, and it's easy to test without instruments. Charge the battery fully, then disconnect either the + or - terminals, so one battery terminal is bare. Presto! No parasitic load. Then leave it for a day or two. Then try to start it. If it doesn't crank or cranks poorly, then the battery is not holding a charge and is indeed defective. If the bike cranks well, then you can (now with some reason) assume that the battery does indeed hold a charge, and go on to seek other causes.
 
Okay, I didn't have time to tank the tank off so I've been checking the battery across the leades I use for my trickle charger. After 36 hrs the battery has held 12.78v. No parasitic drain, and battery is charging fine. When I try to crank the bike the voltage drops to 5.2v and it sounds like the starter isn't engaging. It is making a loud continuous clacking sound. After trying to start the battery voltage is returning to just a little less than it has been prior to starting, about .2v . I can put jumpers on it from my truck to the bike and it will start no problem, no dragging starter sound.
 
When I try to crank the bike the voltage drops to 5.2v and it sounds like the starter isn't engaging. It is making a loud continuous clacking sound.

You say that you can start it if you use booster cables, so the low voltage isn't due to a stalled starter drawing big amps.

Sounds like your battery is done.
 
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Cranking voltage below 9.6 at the battery.

Battery shot.

It sounds like a bad connection inside the battery but I can't see from here. :scratch

Did you get a charging voltage? (engine running)

David
 
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