Author Topic: Electrical charging question.  (Read 985 times)

Offline ComfySofa

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Electrical charging question.
« on: February 02, 2025, 06:21:50 PM »
Was in the garage earlier balancing (or at least trying to) balance my carbs....which is a whole other story (one day ill get "the knack") but so far it eludes me...

Anyway, last week, when i started balancing them (or trying not as well) - i ran out of battery....which did surprise me. Just as a bit of background my 400 has got a completely replaced wiring loom. Its got a Lithium battery and an aftermarket reg specifically for a lithium driven system.

Put it back on the optimate last week and fast forward today. Balancing didnt take as long (its as good as i can get it). So, as a last check i put a meter on the battery as the engine was running which was showing about 12.4-5 volts....if i hold the throttle open slightly it goes up to 12.6v.

Ive got a few reasonably modern bikes (one of which is a z1000 gen4) - i seem to remember that charging about 13 to 13.3 or so. Should the 400 charge at that rate or is 12.6 ish about the right voltage...wondering if its because its a smaller bike, older generator etc etc....

Thanks to anyone that takes a punt at it.

Andy

Offline taysidedragon

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Re: Electrical charging question.
« Reply #1 on: February 02, 2025, 06:28:01 PM »
Your charge voltage seems low. It should be up around 13.5 -14 v with engine running.
Gareth

1977 CB400F
1965 T100SS

Offline ComfySofa

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Re: Electrical charging question.
« Reply #2 on: February 02, 2025, 06:40:47 PM »
Righty...ok..so having the meter on the battery is the correct place to take a reading?

Edit: well - sounds like a new problem....figures as its been about a year to sort out the carbs..!
« Last Edit: February 02, 2025, 06:52:12 PM by ComfySofa »

Offline Bryanj

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Re: Electrical charging question.
« Reply #3 on: February 02, 2025, 07:15:50 PM »
Depends on the regulator, i am old school and dont like lithium batteries or the complicated regulator they need, what is the battery voltage with lights on and running at 3500 rpm?

Offline ComfySofa

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Re: Electrical charging question.
« Reply #4 on: February 02, 2025, 08:50:24 PM »
Ill have to get back to you..! (back in the house now for the night) probably wont be able to get back to it til friday night....stand by!!

Many thanks for the reply back.!

Offline Alexrayz

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Re: Electrical charging question.
« Reply #5 on: February 03, 2025, 07:44:33 AM »
Hey man I had a similar issue with my bike, wouldn't charge, or at least the charging voltage was super low.
In my case it was one of the alternator coils that fried. The regulator was fed with two phases instead of three. As a result the rectified voltage was about the same as what you have.

Normally, at 3500 rpm, you should get 14V max. 12.5V means it is not charging.

I didn't do anything to find that out, my mechanic did this time, so can't really help ya with the research process.

Good hunting and looking forward to read your findings.

Cheers, ride safe!
If it aint broken don't fix it

 

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