Volt meter reading question??

[garyg1957]

I have a 2016 Ultra Classic and have noticed that when bike has sat for a week without starting/running when I go to start it up battery seems very low, starter strains to start bike.  Is this common for these newer bikes, are there things (security system, etc.) that are power-up when bike is sitting that is draining the battery.  Once started the volt meter is constantly reading 14.5 to 15 volts......seems high to this old school mechanic?  Dealer changed out volt regulator at 1000 mile service stating it was defective with above complaint.  I am thinking I have a bad battery, they assured me it wasn't the battery??  Advice, comments, suggestions.....all welcomed and appreciate all input.
Thanks,
Gman       

[Hossamania]

There is some parasitic drain when the bike sits. Use a good volt meter to measure voltage at the battery, before you start it, and after it is running.
When sitting, it should be over 13 volts, and running over 14, up to about 14.7. Don't rely on the dash guage to be real accurate, just close.
You could also have the battery load tested to check its health, though that is not always a perfect test.
There are many threads on this site discussing battery failures, many that are less than 2 years old.
I put mine on a battery tender every few weeks when it is not ridden regularly.

[FLHRI_2004]

. . . I put mine on a battery tender every few weeks when it is not ridden regularly.

I do the same; keeps the battery topped up.

[jbexeter]

1/ traditional lead acid batteries have slightly different numbers than other types, so double check you are looking at the *correct* numbers for your battery.

2/ Unless you've got an old shovel or possibly early evo there are small parasitic loads, alarm etc.

3/ Bike should go a month gradually draining on parasitic loads and still start, with a good battery.

4/ most on vehicle meters are worse than useless when it comes to accuracy, even cheap digital multimeters aren't very accurate, I've seen 5% errors on them and at a nominal 12.000 VDC they could read anything from 11.400 to 12.600 VDC, even a "not quite walmart bargain bin" 2% accuracy will get you 11.760 to 12.24 volts.... so a half decent 0.1% accuracy digital meter will get you 11.998 to 12.012 VDC from a 12.000 VDC source, you're looking at a 50 buck upwards meter here, doesn't have to be a fluke... that's overkill.

5/ charging voltage measures across the battery terminals should be 14.200 to 14.500 VDC, 14.100 is too low and 14.600 is too high.

https://www.w8ji.com/battery_and_charging_system.htm

[garyg1957]

Thanks all for input, I have been using battery tender, after sitting for a day I hooked up tender and it did a battery condition test, stated battery was only 67% charged, reached 100% at 3 amps in about an hour.  I'll have to pull seat and do some test at the battery and see where we are at.....
Thanks Again,
Gman     

[Panzer]

I think you might be forgetting that when you start the bike, the headlight is on which is a big draw on the battery and starter.
Keep the battery tender on......jmo

[motorhogman]

Thanks all for input, I have been using battery tender, after sitting for a day I hooked up tender and it did a battery condition test, stated battery was only 67% charged, reached 100% at 3 amps in about an hour.  I'll have to pull seat and do some test at the battery and see where we are at.....
Thanks Again,
Gman     

Per HD service manual:  28 AH battery

Battery at 75%  charged, needs 3 amps for 2.5 hours to get to 100% charge.

[koko3052]

I think you might be forgetting that when you start the bike, the headlight is on which is a big draw on the battery and starter.
Keep the battery tender on......jmo

That's why I hooked up a relay that cuts all the lights when you touch the start button....but I do prefer a seperate HL switch.
I hate push starting!

[smoserx1]

I am thinking I have a bad battery, they assured me it wasn't the battery??

Lots of good advice here, but I am thinking you are right about your battery.  About half the ones I have had died suddenly, the others gave me plenty of warning, just like you describe.  Yes newer bikes do have parasitic loads, but they should be small.  When batteries begin failing to maintain a charge while sitting it is often from ever-increasing internal resistance, which is pretty much a sign the battery is headed for the graveyard.

[Evo160K]

Did I read the battery is supposed to set for a couple of hours after coming off of the charger before checking the voltage?  Something about dissipating the surface charge??

[motorhogman]

Did I read the battery is supposed to set for a couple of hours after coming off of the charger before checking the voltage?  Something about dissipating the surface charge??

Probably right.  Think I have seen let it sit for an hour after full charge. 

[harley_cruiser]

Did I read the battery is supposed to set for a couple of hours after coming off of the charger before checking the voltage?  Something about dissipating the surface charge??

You CAN get a reading higher than 12.7 after a charge, I have seen guys brag about their 14 volt batteries, but this surface charge will dissipate pretty quick. Give it a crank.
Anything lower than 12.5 you should start planning on a new battery, 12.4 or lower and you are asking for a walk home.