[TLeonard]

Ok, so I have a 20' RGS and keep it on a Battery Tender Plus all the time. I rode for about 45 min up the highway, stopped and had breakfast and hung out for about 90 min. Volt meter reads 14 while running. Turned igntion on, all lights, fuel pump came on like normal, hit starter switcth and nothing. No crank, no start.

I have an Antigravity micro start XP-1 and associated pigtail hooked to battery. All connections are clean & tight. Plugged in XP-1 and biked started with slight delay on cranking. Not slow or weak, just not immediate. I didn't wait long once I plugged in xp-1 before starting.

Headed out and rode for about an 1.5 Hrs, stopped and hung out, had lunch. When leaving, bike started but cranked a little slow before starting. Volts read 14. Rode back for an hour, parked bike for 2.5 - 3 hours. Time to head out, turn ignition on, all lights come on, no crank, no start again. Used Xp-1 again, took a few tries to get it to fire but it started and I made it back 45 min to home and parked it.

I let it sit for a few hours, started right up.

I left it off the tender for the night and checked voltage in the morning - 12.25 and 10.2 at crank, 14.1 at idle.

I did this same test over next few days, lowest reading 11.38 / 8.9 at crank, 14.1 at idle. Started no problem, no hesitation.

The pigtail for the XP-1 is the only accessory that I have added to the bike that requires power. Honestly, I put this in my bag as a part of a growing tool kit I am putting together. Thankfully, I had it.

I am using a digital probe, I don't have a multimeter so I haven't check for parasitic draw yet.

I did check codes and it shows U0100 - Lost communication w/ECM under the radio, none on ecm, bcm or abs.
I do ride with a Cardo Packtalk and was having issues with it toggling back and forth between bluetooth on phone and FM on radio. Kept losing connection like it was buffering.

I admit, I'm not great with electrical but understand some basics.

I appreciate any thoughts, advice and help on this. I am reluctant to get stranded somewhere and not be able to get it started with the XP-1.

Thanks

 

[Thermodyne]

VOM is the first step, the dash gauges are not to be trusted.

12.25 is not charged much. Two things that jump out at me, sans vom numbers. The battery may need to be run through a regen cycle, because of all the time it's spent on the tender. And there might be a regulator issue, you'll need to see what the voltage is out on the road with the vom.

 

[TLeonard]

VOM is the first step, the dash gauges are not to be trusted.

12.25 is not charged much. Two things that jump out at me, sans vom numbers. The battery may need to be run through a regen cycle, because of all the time it's spent on the tender. And there might be a regulator issue, you'll need to see what the voltage is out on the road with the vom.

I will pick up a VOM asap, was hesitant to post this question w/o those numbers. When checking voltage on the road, what's the easiest way to connect VOM? Apologies in advance for all the noob questions that are about to follow re VOM usage.

 

[Thermodyne]

Easy is to just connect it to the battery tender plug.

A little more accurate would be the battery cable at the starter and a ground on the engine cases.

 

[jp7430]

That 8 volts during start is a tad low and also be mindful of static voltage reading. Just off a charger or even a tender, that is surface voltage, not the actual voltage. Hit the start button for just a bump, then read voltage. That will knock off the surface voltage and give you the real level of battery state.

as far as VOM vs gauge reading, compare between the two on a reading while idling…that should give you an idea of what you need to add or take away, if anything, no need to do crazy stuff like attempting to measure with VOM while riding.
My guess…and it is a guess, if gauge is showing 14 in a ride, your stator and regulator are likely working as they should. A weak cell in a battery will do exactly what you are experiencing.

 

[TLeonard]

Easy is to just connect it to the battery tender plug.

A little more accurate would be the battery cable at the starter and a ground on the engine cases.

I wasn't sure about using the battery tender plug with VOM, I have been using it with the probe for numbers to this point.

 

[Thermodyne]

I wasn't sure about using the battery tender plug with VOM, I have been using it with the probe for numbers to this point.

On the M8's, it goes right into the power center through a fuse.

 

[TLeonard]

That 8 volts during start is a tad low and also be mindful of static voltage reading. Just off a charger or even a tender, that is surface voltage, not the actual voltage. Hit the start button for just a bump, then read voltage. That will knock off the surface voltage and give you the real level of battery state.

as far as VOM vs gauge reading, compare between the two on a reading while idling…that should give you an idea of what you need to add or take away, if anything, no need to do crazy stuff like attempting to measure with VOM while riding.
My guess…and it is a guess, if gauge is showing 14 in a ride, your stator and regulator are likely working as they should. A weak cell in a battery will do exactly what you are experiencing.

the 14 Volts that I have read have been both at idle with digital probe and the gauge on the dash. I have been turning on the ignition so lights and everything come on, letting it sit for a few minutes before testing voltage at Battery Tender plug and then at Idle also.

 

[Rob-B]

Is this an AGM battery?

 

[TLeonard]

Is this an AGM battery?

It’s the Original Battery. I bought the bike in December of 2020.

 

[hawk06Glide]

@TLeonard "I did check codes and it shows U0100 - Lost communication w/ECM under the radio, none on ecm, bcm or abs. "

That code usually points towards a bad battery. I would suggest load testing the battery outside the bike. You can buy a manual load tester at an auto parts store. The dealership could also test the battery for you even if it isn't a Harley battery. Don't overthink the problem.

Simple tests you can do is key off and key on voltage, as well as cranking. You'd want to pull the seat off and test these numbers directly at the battery. If the battery drops more than 1 VDC between key on and off, you have an issue. If the battery drops below 10.5 VDC cranking you have a problem. All pointing towards the battery.

Sounds like to me as though the charging system is doing what it is supposed to be doing if you're getting at least 14.5VDC. This is of course assuming you have the seat off and physically tested at the battery.

Next question I have is this, is this a regular AGM or a LiFE battery?

 

[TLeonard]

@TLeonard "I did check codes and it shows U0100 - Lost communication w/ECM under the radio, none on ecm, bcm or abs. "

That code usually points towards a bad battery. I would suggest load testing the battery outside the bike. You can buy a manual load tester at an auto parts store. The dealership could also test the battery for you even if it isn't a Harley battery. Don't overthink the problem.

Simple tests you can do is key off and key on voltage, as well as cranking. You'd want to pull the seat off and test these numbers directly at the battery. If the battery drops more than 1 VDC between key on and off, you have an issue. If the battery drops below 10.5 VDC cranking you have a problem. All pointing towards the battery.

Sounds like to me as though the charging system is doing what it is supposed to be doing if you're getting at least 14.5VDC. This is of course assuming you have the seat off and physically tested at the battery.

Next question I have is this, is this a regular AGM or a LiFE battery?

Tomorrow I will have a VOM and will test the battery at the battery vs the Battery Tender plug. Also, I will take the battery and have it bench tested.

I haven't had the battery out of the bike at this point so I don't know what type of battery it is.

 

[TLeonard]

Thank you for the replies and suggestions so far. I appreciate the help, You guys are awesome!

Once I have a chance to check it with the VOM as well as have it tested, I will post that information.

Thanks again!

 

[FATBOY1994]

It’s the Original Battery. I bought the bike in December of 2020.

Buy a new battery.

 

[TLeonard]

Ok, so here’s what I have at the battery
With ignition switch off ~ 12.7
bumped starter and checked voltage ~ 12.46
At Idle ~ 14.10

 

[skratch]

you aren't checking the voltage with a starter bump, you need to crank it and see how far it drops while cranking.

 

[TLeonard]

you aren't checking the voltage with a starter bump, you need to crank it and see how far it drops while cranking.

No, I did a bump start to clear any surface voltage and then cranked it over. It was a little slow cranking and it dropped to 10.1 during cranking.

 

[skratch]

looks to me like your battery is going dead. i don't know your location, but here in louisiana, the heat kills batteries. if i get 2 years out of one, i consider myself lucky. the one i have now is one of the longest i have had, and it's on year 3. the wife's died last year and i have been expecting mine to follow shortly after, but seems to be doing okay. though, usually mine just up and quit. don't even have the decency to give any warning beforehand.

 

[TLeonard]

looks to me like your battery is going dead. i don't know your location, but here in louisiana, the heat kills batteries. if i get 2 years out of one, i consider myself lucky. the one i have now is one of the longest i have had, and it's on year 3. the wife's died last year and i have been expecting mine to follow shortly after, but seems to be doing okay. though, usually mine just up and quit. don't even have the decency to give any warning beforehand.

It’s looking like that’s all it is ~ I’m trying not to overthink this and look for a problem that isn’t there.

 

[jwade420]

looks to me like your battery is going dead. i don't know your location, but here in louisiana, the heat kills batteries. if i get 2 years out of one, i consider myself lucky. the one i have now is one of the longest i have had, and it's on year 3. the wife's died last year and i have been expecting mine to follow shortly after, but seems to be doing okay. though, usually mine just up and quit. don't even have the decency to give any warning beforehand.

I will second the battery going out. Same deal with the heat killing em in Southern Oklahoma. I've tried keeping em on a tender and not using one at all. Both ways about 2 years is all I can get from one. My '20 RGS was delivered to dealer in July of '20 and I am experiencing some slow turnovers that just started so I will be replacing it soon. I quit using the tender when the bike started fine as I left for work one morning but would not turn over at lunch time. Had to jump it to get home.