Lately I've been having some trouble starting my bike, I've got a 2012 Fat Bob with the original battery - Which has been on a CTEK charger since I got it.

Just to put it all out there I have noticed it taking longer to turn over, I'm not sure when it started but I just attributed it to age and didn't worry about it ... or that stupid neutral safety switch under the clutch lever (I've had some trouble with that in the past) But the bike always started pretty quickly, and if it was warm immediately.

The other day though I got home, plugged in the trickle charger, but then forgot to turn off the bike. When I went out to the garage the next morning I found all the lights flashing and of course nothing worked. I turned it off and left it charging for awhile and eventually I got it to start, reluctantly, but it's never been the same since. It takes a long time (days possibly) for the charger to ever say it's done charging now and if I leave it off the charger for to long it sounds like its struggling. Yesterday when I tried to start it I noticed the battery light flash, and I've seen it once more since then.

The dealer hooked it up to a battery tester which says the battery is in great shape and there is absolutely no cause for concern, but obviously something is wrong. He did say the cold cranking amps were a little low, but I don't know how low and he didn't seem to concerned about it since everything else was well within the green.

I'm at a loss here, I don't know what the problem could be? I'm fine with buying another battery if I have to, but I'm not sure that would solve the problem if every test says the battery is ok? The CCA are what start the bike though, so if that's low maybe a new battery would fix it, any other ideas?

Thanks for your help

 

First thing you should do is get a multimeter and test your battery. Then test it running to see if your charging system is working correctly.

 

Get a new battery. It's probably warn out.

Some electrical 101 and a little more...

Rev. 091615

Remember, the best made brand new battery that has been on a maintenance charger for 3 days that has a loose or bad connection is no better then a boat anchor with a loose rope. The connection can get loose after one ride if the battery is not anchored and the wires are short and get tugged in a direction that can unscrew the bolts.

After a good 24+ hour maintenance low amperage charge, with the charge light in the solid green and the battery has set about 24 hours off charge, voltage should be about 12.8 volts.
12.8 = full charged
12.6 = 75% charged
12.3 = 50% charged (Lot of new modern cars with system protection will not even click at this point but will have good headlight beams showing)
12.0 =25% charged

Always check both the terminals at the battery lead and also at the terminal on the wire. That helps to verify connection. With a DC volt meter (one that has a feature to lock high and low reading is best) hooked across the battery terminals and reading 12.8 or so, crank motor and while its cranking it should not drop below about 9.6 volts and as soon as it starts and throttled up to 2000 rpm, voltage should read around 14.8 volts. The 2000 rpm is the bench mark standard. Ignore idle output. Ignore output above 2000rpm unless it exceeds 14.9 volts. That is a sure indication that regulator is bad.

The crank check shows a rough check of the reserve amperage capacity of the battery while cranking with a 150-200 amp load on it. The 14.8 shows a good alternator and if you leave it on a while as the regulatory will drop the voltage a little showing itself working. However, with the lights and stuff always on, it will never drop back much. If you have a lot of options, most modern bikes will not show 14.8 charging volts at idle but stock newer bikes will be close. Older bikes with lower amperage output not so much. However, 2000 rpm is the bench mark for the standard 14.8 volts.

If you think battery is good and something is draining it sitting, now would be a good time to check for drain problems. Go to Harbor Freight and get you a AC/DC meter for under $25 or so. http://www.harborfreight.com/ac-dc-d...ter-37772.html Make sure it has DC amps draw, DC voltage, resistance and AC voltage. Key off. Remove the negative cable off the battery. Set meter on DC amps. Hook the meter lead to cable and the other to battery. How many milliamps (mA) is it drawing? It should be no more then 6 mA which is the ECM (1), speedometer (1), tac,TSSM (1),HFSM (1) and voltage regulator (1)

When a battery wears out, a good charge will show fairly good voltage, but the battery can still have very low amperage capacity which will show in the crude crank test above, but it really should be checked after a good charge by removing it from bike and getting a free check at a place like AutoZone that has a fancy load meter check that gives you a print out of the battery health. Battery MUST BE CHARGED to check it. Be sure they set their meter to correct cold cranking amperage stated on the battery. Never charge the AGM absorbed glass mat battery with a regular car battery charger unless it is a newer one that says safe with this type of battery. Also, by taking battery out you now know you have good connections. Vibration tends to loosen the connections or a little corrosion will prevent charging or cause starting problems.

Using the maintenance charger can get more years from a battery but be careful here. You do not want the last start 5 miles from home. If it still grunts when you first hit starter or kicks back with a bang, replace it. After a few years, charge and pull battery and have it checked for cold cranking amperage ever spring. Even then, if it grunts most ever start, I would replace it. Most battery checkers at AutoZone and places like that do not do really well on the low amperage setting on small batteries. Not sure why but they tend to say they are OK when they are weak. If they have one that fits your bike, Wal-Mart's AGM absorbed glass mat battery is just as good as any for one third to half the money of a Harley Battery. Do not put an old fashion one with vent tubes on a modern TC Harley. Do not jump, push start or run bike with a half dead battery except in an emergency. If a bike battery is down and you jump it, throwing all that amps to it from a big car battery especially one that is running can wreck a bike regulator or charging system. Charging a worn out battery can kill alternator stator or the voltage regulator or both. Probably ending in a big dollar repair.

It is also a good idea to always check your battery at 2000 RPM with your meter set to AC. If by chance, the regulator goes bad, sometimes it will let AC come thru. That is a sure sign of a bad regulator. The older stators with two wires are a two phase AC system. Lot of people call it a single phase but it is two phase. The AC voltage you see appears single since you check it AC across the two wires since there is no earth ground. If you were to check one wire to an earth ground, it would show one half the voltage that you would see when you check the two wires together on the bike. Same with the other. Together they double and are two phase. The newer three-wire system is a 3-phase AC system for the higher amperage output.

Also remember, when starting a Harley, hit the starter and hold it in till it is firing on both cylinders and running before letting up. If you let up before it’s running, quiet often, it actually take an FI motor longer to start. There is a fraction of a second more for a long stroke Harley then a multi-cylinder car for it to get going. If you do not do this, it will kick back with a bang, sneeze thru the intake or crank a lot longer the second time or shame on you the third time. Also, if you have a habit of doing this, the starter solenoid switch contact will only have half the life it could. You cannot hurt the starter. The starter gear has a sprag clutch. There are drive pins in it that as the gas motor catches and run, it outruns the starter motor drive and disengages it from the electric motor. If you hold it in a little too long and listen carefully, you will hear the sprag clutch run up the ramps and slip. Makes a sizzle hum. This will show you your starter sprag clutch is OK.

 

Agree, just go buy a new battery.
Good post Ripsaw.

 

Put a cheap aftermarket battery in your bike, save $50, and BOHICA

Or put in the correct Harley Davidson battery that was engineered and built specifically for your Harley Davidson and ride for another 5 years.

Regardless of what some well meaning but naive members say, there IS a difference, and that difference may be the difference between you being stuck in the boonies with a dead battery or putting on down the road without a care...

Your choice...you can save $50 or have confidence that you have the best battery available in your ride...choose wisely...

But, before you buy another battery, you need to check your system. It is simple if you can use a voltmeter and understand what you are doing.

How low does the battery voltage drop across the terminals when you are cranking ~ >9.5 vdc, minimum.
How much voltage is at the battery terminals when the bike is running ~ 14 vdc minimum

Check these two things and come back with the results.

 

Thanks Guys, I'm just catching up on this now for some reason I never got the notifications. I'll go through all of this information more thoroughly when I get home but I'm fairly sure the dealer checked all of this, I saw him check some of it. If the consensus is the battery probably needs to be replaced then that's what I'll do. The tester said it was fine but as I said he did mention the CCA was low and I've seen the battery light flicker which I assume is a warning to replace the battery. I can believe there is some room for error in these testers I just wanted to make sure there wasn't anything I was missing before I needlessly bought a battery that didn't fix the problem.

I might as well wait for summer then, the bike will be parked for the winter soon anyway.

Thanks again

 

I wouldn't wait for summer. Just in case it isn't the battery and you lose saddle time when summer starts while you're trying to fix it. Get the new battery and hopefully that will cure the problem. You said you have a trickle charger, but get a battery tender and keep it on the battery all winter.

 

Running on a crappy battery (the kind that will go dead if left sitting more than a week except on a trickle charger) is asking for trouble. It can also lead to stator failure.

 

i was going through a similar thing with mine.

pulled the battery box and found some corrosion on the wire from the battery to the starter. cleaned it up and put some dielectric grease on and she fires right up again.