• Don't overlook our Welcome Package, it contains many links to important and helpful information about functions at VHT like posting pictures and sending PMs (private messages), as well as finding the parts you need.

    AD

Battery Charge Problem

450roo

Veteran Member
Joined
Nov 10, 2020
Total Posts
242
Total likes
26
Location
Adelaide, South Australia. Australia
Just back from a 150 mile ride on the K3, I have a volt meter fitted and I noticed early on the voltage was down to about 12.2 instead of the usual 12.9 this is with the lights on, battery is about 6 months old.
About an hour and a half into the ride I stoped to rub my B and noticed it would not idle, but ran well otherwise. At this stage the voltage was a constant 11.7 but still running well except for the absent idle.
A little further on I stopped and the starter would not work, but the bike still ran well (good old kick starter!) Rode home, about 70 miles in this condition. The battery is now charging.
My thoughts are a coil on the alternator has dropped out. The other possibility is the after market regulator/rectifier has a problem.
Before I start trouble shooting, has anyone had problems with these regulator/rectifiers braking down and if so what are the symptoms and how can you test them?
 
You likely NEED a new battery now.......Or at least, ALL those symptoms point in that direction......

What type battery do you have?...(lead-acid, AGM, Lithium?).... I suspect that somehow your battery got "cooked"....This is most likely if yours is lead/acid.......
 
The battery is a Motobatt AGM and as said 6 months old, has about 2000 miles of use. Winter over here!
I put it on charge when I got home checked it a moment ago and the smart charger says it is now fully charged, checked the voltage immediately after charge and it shows 13.7 volt checked again 10 minutes later and got 13.5. Will see what it says in the morning.
Thanks for your suggestions, always a help to hear what others think!
 
I don't recall - are you using the stock Voltage regulator? Is the switch in the headlight switch that connects the yellow and white wires still in circuit, or bypassed? If that switch is still in circuit, it could be disconnected somewhere, and not turning on the extra stator output to support the headlight.
 
Did you check the current drain when the bike is turned off ? It should be 0 at all times, 100 % open circuit when the ignition switch is turned off.
 
Thanks all for the suggestions, I will keep them in mind. Have not started serious trouble shooting yet, but can say the white/yellow wires are soldered together at the alternator plug.

My main question was what symptoms to look for on a faulty modern combination rectifier/voltage regulator, can it be responsible for a lower voltage or do they stop working altogether? I am puzzled by the motor running indefinitely, on the reduced but steady 11.7 voltage. Suggests that I was running on the regulator out put?

I am busy for the next two days then I will get stuck into it. Might rule out the battery being the problem by putting it in the K2 and taking that for a ride?
Will let you know of developments as they occur.
 
I've only owned one of the modern units myself (Oregon Cycle rec/reg) and it was on my bike when I bought it, so I have zero long-term experience other than mine still works fine with no knowledge of how old it really is (and it has to be more than 5 years, I've owned the bike that long)
 
Have had little time to trouble shoot but I have ruled out the battery (sorry Steve, it is not often you are wrong) I tested it this afternoon about 24 hours after it read full charged when I had 13.7v it still has 13.2v. Fitted it in my K2 took it for short run and it shows a constant charge of 13.9v will go for a longer ride Friday.
Next opportunity I will check the alternator output, if that is OK it must be the voltage regulator?
Will let you all know the result.
 
I STILL think it is your battery, although a weakened alternator/charging system could contribute to the problem.......

Just for fun, let's use a steamship boiler as an analogy......
The fire in the boiler represents the bike's electrical usage......
There are two stokers shoveling coal for the fire....
Stoker #1 represents the battery output, and has a specific amount of coal stored in his coal bin......
Stoker #2 represents the alternator output and while he has a virtually unlimited supply of coal in his bin, he can only shovel relative to engine speed (RPM), AND, he is throwing an occasional shovel-full into Stoker#1's bin so he doesn't run out.....

Now, let's refer to your original post:
"Just back from a 150 mile ride on the K3, I have a volt meter fitted and I noticed early on the voltage was down to about 12.2 (#!'s bin is low) instead of the usual 12.9 this is with the lights on, battery is about 6 months old.
About an hour and a half into the ride I stopped to rub my B and noticed it would not idle,(#1 very low, #2 can't shovel fast enough at idle RPM's to refill#1 and keep fire high enough) but ran well otherwise. At this stage the voltage was a constant 11.7 (Stoker #1 too tired to help much if at all) but still running well except for the absent idle.
A little further on I stopped and the starter would not work, (#1 bin virtually empty) but the bike still ran well (good old kick starter!) Rode home, about 70 miles in this condition. (Stoker #2 doing virtually all of the work...) The battery is now charging.
My thoughts are a coil on the alternator has dropped out. The other possibility is the after market regulator/rectifier has a problem.
Before I start trouble shooting, has anyone had problems with these regulator/rectifiers braking down and if so what are the symptoms and how can you test them?

Note that running on the alternator/charging system alone CAN damage those components......
 
I STILL think it is your battery, although a weakened alternator/charging system could contribute to the problem.......

Just for fun, let's use a steamship boiler as an analogy......
The fire in the boiler represents the bike's electrical usage......
There are two stokers shoveling coal for the fire....
Stoker #1 represents the battery output, and has a specific amount of coal stored in his coal bin......
Stoker #2 represents the alternator output and while he has a virtually unlimited supply of coal in his bin, he can only shovel relative to engine speed (RPM), AND, he is throwing an occasional shovel-full into Stoker#1's bin so he doesn't run out.....

Now, let's refer to your original post:
"Just back from a 150 mile ride on the K3, I have a volt meter fitted and I noticed early on the voltage was down to about 12.2 (#!'s bin is low) instead of the usual 12.9 this is with the lights on, battery is about 6 months old.
About an hour and a half into the ride I stopped to rub my B and noticed it would not idle,(#1 very low, #2 can't shovel fast enough at idle RPM's to refill#1 and keep fire high enough) but ran well otherwise. At this stage the voltage was a constant 11.7 (Stoker #1 too tired to help much if at all) but still running well except for the absent idle.
A little further on I stopped and the starter would not work, (#1 bin virtually empty) but the bike still ran well (good old kick starter!) Rode home, about 70 miles in this condition. (Stoker #2 doing virtually all of the work...) The battery is now charging.
My thoughts are a coil on the alternator has dropped out. The other possibility is the after market regulator/rectifier has a problem.
Before I start trouble shooting, has anyone had problems with these regulator/rectifiers braking down and if so what are the symptoms and how can you test them?

Note that running on the alternator/charging system alone CAN damage those components......

Of all your life's involvements and professions, it's obvious you must have been an Engineer on a locomotive for a few minutes along the way... :dizzy:
 
Thanks Steve! I confess a little doubt about the battery, from memory the usual voltage fully charged was somewhere in the region of 12.7 now it is reading 13.7 full charge which seems unusual.
Will keep the investigation going!
Once again thanks for the help, it is wonderful to have you all to talk to! Will let you know what I find.
 
Fitted new battery and new new voltage regulator, took it for a 120 mile run this morning and all seems well, with lights on a steady 14.2 volt. I am happy with that.
Thanks for holding my hand guys!
 
Back
Top Bottom