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Old Oct 8, 2015 | 01:43 PM
  #11  
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Rev. 100815
Some electrical 101 and a little more..

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.
 
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Old Oct 8, 2015 | 01:53 PM
  #12  
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EVERY vehicle should last 3 months without a battery tender.
All modern vehicles have electronics, such as burglar alarms, clocks or whatever. These draw negligible current. They are designed with the whole vehicle in mind (including the battery). A battery tender or other charger should never be needed when storing any vehicle for 3 months or less.
 
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Old Oct 8, 2015 | 02:44 PM
  #13  
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If your battery loses some of it's charge overnight, something is wrong. You do not need a battery tender on it all the time. That is bullshit, and it's hard to believe that some people fall for it.
 
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Old Oct 10, 2015 | 06:54 PM
  #14  
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If you still have a warranty, let the dealer find the issue. Yes, read your hand book. Purchase yourself a 2014 Touring HD Service Manual at the dealership. Good luck.
 
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Old Oct 10, 2015 | 10:55 PM
  #15  
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OP wrote above:
[[ when I asked service manager he said they recommend using a battery tender all the time! ]]

That's exactly what I'd recommend, as well!

I'm still using the factory battery in my '07 Road Glide...
 
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Old Oct 11, 2015 | 08:57 AM
  #16  
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Originally Posted by Fishrrman
OP wrote above:
[[ when I asked service manager he said they recommend using a battery tender all the time! ]]

That's exactly what I'd recommend, as well!

I'm still using the factory battery in my '07 Road Glide...
I have the original battery in my 2008 NT, and don't use the tender all the time, only when stored for more than a couple of months.

You may recommend it, and it can do no harm, but that does not make it a necessity and there's nothing to suggest that your use of the tender all the time played a role in your original battery still working.
 
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Old Oct 11, 2015 | 09:28 AM
  #17  
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Have to agree it's going down to fast if it's still under warranty , they need to do something about the problem
 
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Old Oct 11, 2015 | 09:38 AM
  #18  
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Originally Posted by Fishrrman
OP wrote above:
[[ when I asked service manager he said they recommend using a battery tender all the time! ]]
That's exactly what I'd recommend, as well!
I'm still using the factory battery in my '07 Road Glide...
If your battery is still good after all this time, it isn't because you used a battery tender all the time. You just got lucky and have a good battery. Do you use a tender on your car battery?
Using a tender all the time is unnecessary, don't fall for it, OP.
 
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Old Oct 11, 2015 | 10:02 AM
  #19  
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OP, how long does the engine run after you start it? I can't say for sure that there's a problem unless I know that the battery has what should be enough time to recharge after sitting/starting.
 
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Old Oct 11, 2015 | 10:12 AM
  #20  
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Get a load test done before you end up somewhere and need to be towed.

A healthy 12 volt motorcycle battery should maintain a range from 9.5 - 10.5 volts under the load for a good 30 seconds straight. If the battery begins to hold and then steadily drops in voltage, there is a problem. If the voltage drops below 9.5 volts, the battery has very low capacity and should be replaced.
 
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