Does your brake light glow slightly?

Go to HF and buy a cheap multimeter ($7), you can check the battery yourself while you wait for the shop to get your bike in. You can even check for amperage draw when bike is off, just to see how many milliamps going out. That would tell you if there is some abnormal current draw.

John

 

Don't know if they have Harbor Freight over in the UK.

 

Hi John
thank you for that 👍 I do have a multimeter but I am ashamed to say I don’t know how to use it 🤭🤣🤣

but I have a mate who would check it for me I will pop and see him 👍

cheers John
Alby

 

I use a multi meter every day almost. But a lot can be done without. Its a new bike, I wouldn't start with parasite draws.

Charge bike on charger, let it sit off charger, if it doesn't start in the next day or two most likely battery. Which is what I guess it is.
If you want unhook battery to prove not a parasite draw.

Most likely failure is battery, or he is not riding enough to charge it. Going to miles to work every day might not be enough, if that is the case.

As for the simplest test with meter put it on DC volts and put one lead on each battery post. If you don't know where to turn dial, keep turning until you get around 12.7. Start bike rev it up to 3-4k rpm, should go up to around 14.4 volts at battery. If it doesn't issue is volt reg or stator most likely. I would not tear into it on a new bike. But there are plenty of videos on testing AC output of stator, which I am guessing should go up to around 80-100 volts ac when revved up. J&P has good video I think,


But lets not over complicate this, charge it, and let it sit 1-2 days, if it doesn't start, most likely battery.

 

Battery on my Sportster S failed. Voltage was good but the CCAs were very low so it would not start the bike. Everything else checked out ok (charging system, etc…).

HD recommends having these bikes (RevMax) on the tender pretty much anytime the bike is parked. I feel it’s most definitely a flaw and the battery will most likely need to be replaced every few years.

With the new warranty battery from HD, I have yet to have an issue with the bike starting. When I first got the bike it rarely started on the first try and things just kept getting worse but now it always starts on the first attempt.

 

Well having ridden the bike 70 odd miles yesterday, I didn’t put the bike on the trickle charge to just see if it kept its charge. I tried it on twice today a few hours apart and it started both times straight away.
We have just come back from dinner and pulled the cover up and this is what we saw the rear light was glowing fairly brightly. So it seems that Harley were right !!
It was good to find that really 👍
I have tried to add pictures but it won’t let me 🤣

 

What was harley rigtht about? You proved it will go a day. Seems battery is kind of ok. If you really want to test it, leave it off for 2-3 days, but one day is a decent start. Maybe things have radically changed for the worse, and they may have, but a bike should sit for atlest 5 days. My rushmore with fob goes couple weeks, my older ultra will go a few weeks or so .
How can you travel, if you cannot go over night without a tender?

Some people I know were talking about dealers not being able to start bikes because of the batteries. I thought they were being dramatic. Maybe not.

 

"when the weather is hot there is a voltage leak that makes the brake light glow very slightly" The tech at HD said it was one of the handlebar controls, so it appears he may be correct considering the symptoms reported by the OP.

John

 

That's interesting, wonder why.

 

"the service department girl heard this and she remembered me from my first service she did go in the workshop and speak to one of the technicians for me, and she came out to me and said there is a warranty issue with the Nightster where when the weather is hot there is a voltage leak that makes the brake light glow very slightly???? " Your retention and comprehension skills are seriously lacking