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Re: Got a "tiny" charging problem...
Posted: Mon Oct 20, 2025 4:22 pm
by Rob Frankham
In the first instance, you really do need to sort out why the charge lamp isn't lighting. The tests you have done suggest that the problem is in the wiring or conductors between the bulb and the voltage regulator/diode board (i.e. the blue wire) or between the bulb and the positive supply.
You don't say what happens with the other bulbs in the dashboard, the oil lamp, the neutral lamp etc... This will give you a valuable lead since, if these are working, you have battery voltage to the dash so the problem is either in the dash or in the blue wire. If they're not, then it's a rerasonable assumption that there is a problem with the 12 volt supply to the dash.
The 12 volt supply to the dash comes from the engine stop switch using a Green/Blue wire. This wire goes via a multiconnector under the tank. You can assume that the switch is getting power because the bike starts and runs (and the ignition system an the starter both use power taken from the switch branching off after the undertank multiconnector.
Conclusion:
1) There is either a break in the blue wire between the dash and the voltage regulator or
2) There is a problem with the multiconnector attached to the underside of the dash or
3) There is a problem with the copper tracks on the flexible printed circuit in the dash or
4) There is a break in the green/blue wire between the dash and the engine stop switch.
Get the light working as a first priority... if the bike still doesn't charge then you need to go on to the next fault... one thing is foir certain though, if the charge light isn't working, the bike won't charge...
Rob
Re: Got a "tiny" charging problem...
Posted: Tue Oct 21, 2025 1:37 am
by Kermit
gspd wrote: ↑Mon Oct 20, 2025 3:20 pm
Just a tip. As shown in your first pic, your brush tension spring is too 'loose'. You should wind it a full turn tighter. Remove the stator and check the inside one also.
Ok, got it. I will be trying to make these spring a bit "tighter". The front one might be easier than the back, as the latter's wire seems a little shorter, which already makes the brush to stick out less from its housing (compared to the front one).
Re: Got a "tiny" charging problem...
Posted: Tue Oct 21, 2025 1:52 am
by Kermit
Rob Frankham wrote: ↑Mon Oct 20, 2025 4:22 pm
In the first instance, you really do need to sort out why the charge lamp isn't lighting. The tests you have done suggest that the problem is in the wiring or conductors between the bulb and the voltage regulator/diode board (i.e. the blue wire) or between the bulb and the positive supply.
You don't say what happens with the other bulbs in the dashboard, the oil lamp, the neutral lamp etc... This will give you a valuable lead since, if these are working, you have battery voltage to the dash so the problem is either in the dash or in the blue wire. If they're not, then it's a rerasonable assumption that there is a problem with the 12 volt supply to the dash.
The 12 volt supply to the dash comes from the engine stop switch using a Green/Blue wire. This wire goes via a multiconnector under the tank. You can assume that the switch is getting power because the bike starts and runs (and the ignition system an the starter both use power taken from the switch branching off after the undertank multiconnector.
Conclusion:
1) There is either a break in the blue wire between the dash and the voltage regulator or
2) There is a problem with the multiconnector attached to the underside of the dash or
3) There is a problem with the copper tracks on the flexible printed circuit in the dash or
4) There is a break in the green/blue wire between the dash and the engine stop switch.
Get the light working as a first priority... if the bike still doesn't charge then you need to go on to the next fault... one thing is foir certain though, if the charge light isn't working, the bike won't charge...
Rob
Hi rob,
You might have seen I've made a bit of progress regarding this issue.
I'm learning a lot on my bike with this kind of explanation though. Reading you, it makes a lot of sense. In front of a stranded motorcycle, that's another story. But again I'm learning.
Thanks for your input on the topic.
Re: Got a "tiny" charging problem...
Posted: Tue Oct 21, 2025 7:42 am
by Rob Frankham
My apologies, read the first page and thought it was a new post.
Re: Got a "tiny" charging problem...
Posted: Tue Oct 21, 2025 4:35 pm
by Kermit
Rob Frankham wrote: ↑Tue Oct 21, 2025 7:42 am
My apologies, read the first page and thought it was a new post.
That was still a great deal of information.
Thank you for that.
Re: Got a "tiny" charging problem...
Posted: Tue Oct 21, 2025 4:39 pm
by Kermit
No progress today. Went back home a bit late. Same tomorrow, so I guess I will be coming back here with some news on Thursday or maybe during the weekend.
Re: Got a "tiny" charging problem...
Posted: Tue Oct 28, 2025 3:03 pm
by Kermit
Alright, I said I would go back to you and was carried away by some other stuff, as always...
Anyway, a quick message to thank you all for your help as the bike now charges properly.
To sum it all up:
- I started looking at the wrong places (stator, rotor, diode, rectifier) and should have noticed the bulb on the dash wasn't even lighting up when the ignition was turned on (before even starting the bike)
- from this, you guys really help by narrowing the problem down to very few possible issues
- which led me to checking the dash where I could not have the charging bulb to light up with a probe tool
- after a quick check of the bulb, and a good clean of all the contacts, the bulb decided to work again
- after reassembly, the bike was started and voltage checked at the battery to obtain a slowly growing figure from 12.54 to just shy of 13V (depending on the revs). Also the charging light on the dash was properly turning on and off when given revs from tickover.
I cannot thank you enough because:
- obviously you helped me to solve the problem
- your messages were as many reasons to keep on looking and get over my reluctance for electrical issues
- I have learnt a lot in the process.
Cheers,
Jerome
Re: Got a "tiny" charging problem...
Posted: Wed Oct 29, 2025 6:23 am
by Rob Frankham
Just one comment...
The voltage at the battery terminals should read around 14 volts with the engine running at over 3000rpm. It may take a while to achieve that if the battery is low to start with but, if it never gets to that level, there could be another issue. I wouldn't be particularly worried if it sat at 13.8 volts or above. 13 volts will be very slow to charge the battery to full... although it will charge eventually.
Give it a run... if it doesn't achieve a good voltage then suspect the voltage regulator, the diode board or one of the windings in the alternator stator. There are other thiangs but start there.
Rob
Re: Got a "tiny" charging problem...
Posted: Fri Oct 31, 2025 11:42 am
by Kermit
Rob Frankham wrote: ↑Wed Oct 29, 2025 6:23 am
Just one comment...
The voltage at the battery terminals should read around 14 volts with the engine running at over 3000rpm. It may take a while to achieve that if the battery is low to start with but, if it never gets to that level, there could be another issue. I wouldn't be particularly worried if it sat at 13.8 volts or above. 13 volts will be very slow to charge the battery to full... although it will charge eventually.
Give it a run... if it doesn't achieve a good voltage then suspect the voltage regulator, the diode board or one of the windings in the alternator stator. There are other thiangs but start there.
Rob
Got it! I'll give that a try.
Won't be before at least 10 days though. Or maybe more, because the bike being on the lift right now, maybe it's the right time to install this 860cc kit I have laying on the shelves for far too long.
Thanks a lot for sharing your knowledge.