Keep going through batteries
Keep going through batteries
I have an 06 street bob with about 20k on it (I will note that I still have the original charging system but checks out good), and within the last month I've been through 3 batteries (3 month warranty luckily) I know theres a deeper rooted problem that I can't diagnose here.
Im fairly hard on the bike and the day the first battery went was after a few wheelies and spirited runs. Ill be riding and the bike will randomly lose all power for a second or two then comes back on. The last battery I had in lasted 3 weeks without issue until one day the cutting off and on started while out on a ride, next day not enough juice to kick on had the battery load tested and it was spent.
I have tested the whole charging system 3 times and I'm not throwing any codes, everything comes back in spec. No overcharging, no losing power, and I've been over every wire looking for pinches or shorts as well as loose + or grounds and have come back with nothing.
Im now on my fourth battery and it fired right up and as usual seems good to go but I'm not going to keep roasting batteries, so I'm looking for any outside ideas or things to check before I take it to my indy and spend money on something I can most likely fix.
Im fairly hard on the bike and the day the first battery went was after a few wheelies and spirited runs. Ill be riding and the bike will randomly lose all power for a second or two then comes back on. The last battery I had in lasted 3 weeks without issue until one day the cutting off and on started while out on a ride, next day not enough juice to kick on had the battery load tested and it was spent.
I have tested the whole charging system 3 times and I'm not throwing any codes, everything comes back in spec. No overcharging, no losing power, and I've been over every wire looking for pinches or shorts as well as loose + or grounds and have come back with nothing.
Im now on my fourth battery and it fired right up and as usual seems good to go but I'm not going to keep roasting batteries, so I'm looking for any outside ideas or things to check before I take it to my indy and spend money on something I can most likely fix.
Elite HDF Member
Joined: Sep 2008
Posts: 4,440
Likes: 148
From: Northwest
Only a few other components to change in your charging system.. stator, voltage regulator.. and pre 07 were known for having rotten rotors.
Might be worth trying to see how much current your starter is pulling too.
3 batteries? I'd have changed out voltage regulator at least by now... have you checked the output of your alternator? .. jiggled wires?.. loose grounds?
Might be worth trying to see how much current your starter is pulling too.
3 batteries? I'd have changed out voltage regulator at least by now... have you checked the output of your alternator? .. jiggled wires?.. loose grounds?
Yes Ive checked, had the multimeter out three separate times to see if anything was out of spec and everything falls within spec. Ive jiggled about every damn wire possible and nothing. Im not going to jump to throwing new parts on without more of an idea as all signs point to a working voltage reg at the moment.
My guess is its being damaged by the charging system but I cannot figure out what, I've done every test in the manual for the stator, rotor, and voltage regulator and all come back exactly in spec.
Grand HDF Member
Joined: Jul 2016
Posts: 4,384
Likes: 8,742
From: Texas
Yup
Likely one..., or more of those - is breaking down under load / heat / riding conditions
But showing good / working under test conditions
Ghost
But showing good / working under test conditions
Ghost
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That makes complete sense, its for sure once it's being out and ridden. It always starts with the bike momentarily losing all power and coming right back on. Would it make more sense being the stator or the voltage regulator? Changing it all is obviously the best bet but if I can get away with just swapping out a voltage regulator and finishing the season I'd be happy and update stator/rotor come winter.
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Elite HDF Member
Joined: Sep 2008
Posts: 4,440
Likes: 148
From: Northwest
I'd bet the stator, but you need to know.. once one component goes weak, it stresses the crap out of all the others. I had a stator go, and just went ahead and replaced regulator and battery.
Grand HDF Member
Joined: Jul 2016
Posts: 4,384
Likes: 8,742
From: Texas
That makes complete sense, its for sure once it's being out and ridden. It always starts with the bike momentarily losing all power and coming right back on. Would it make more sense being the stator or the voltage regulator? Changing it all is obviously the best bet but if I can get away with just swapping out a voltage regulator and finishing the season I'd be happy and update stator/rotor come winter.
Fully charge the battery
Ride it for 3 or 4 hrs
Park it..., let it cool down just a tad (15 / 20 min) - then immediately hook the charger back up.., and see how long it takes to fully charge
========
This eliminates parasitic draw as a possibility (for the time being)
And
It'll tell you if the bike is actually keeping the battery charged.., while running
Shouldn't take long at all..., if at all - to charge the battery back to full after the test ride
If it does - then the bike.., while running - is drawing off the battery..., and not charging it
If it doesn't take long to charge - then let it sit for a couple of days - and see if the battery is drawn down - (parasitic draw is killing the battery)
Once isolated - we can go from there
Otherwise it going to be a shotgun crap shoot figuring out the culprit
Ghost