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Discussion Starter #1
Hi,

as winter has arrived, battery has been taken out from my bike. I had to add distilled water to my acid battery as electrolyte level was slightly below minimum.

This has led me to concerns regarding charging problems (6V installation). My bike is not equipped with voltage regulator. There is only rectifier (Graetz bridge), so output voltage is full wave rectified signal.

With lights off only one coil AC voltage is transformed to DC voltage, while under increased load (lights on) two other coils from generator are switched on in parallel to increase charging current. All coils are in the same phase so this is not three phase generator. Is my deduction correct?

If so, reducing load by using LED bulbs will result as increased charging voltage. As system was designed for certain load level, with standard bulbs and good connections I should have charging voltage higher than required and my battery will be overcharged. In that case I should replace voltage rectifier or apply voltage regulator as it was not used in original installation.

I would be gratefull for guiding to proper thread, as there are a lot of information there...

cheers,

Andrzej JK
 

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Discussion Starter #2
Hello folks,

even if it looks weird, I'd like to place here reminder how the problem has been solved.

As mentioned above, charging system is based on three coils working in single phase. Without lights one coil is supply for voltage rectifier (load should be ca 4,3A for ignition coil shorted). With lights on remaining two coils are switched on to support power balance of the system. As there is no voltage regulator, to keep battery charged with proper voltage and current You would need to keep power consumption in balance as close to original lights power as possible. It was the case for too high voltage. Reducing power consumption by applying LED bulb instead of original one (25 W) has resulted increased charging voltage.
 

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Yes, you got it figured out.

My CL450 wasn't charging well years back and my headlight switch failed so I shorted the yellow to the yellow/white wire in the headlight. Always got full charging current that way. Years later charging capacity fell off so I replaced the magnet with a stronger one. Then charging was too high. I tried various voltage limiters from a wrecking yard with no improvement. With the help of others on this forum I reverse engineered the Honda voltage limiter, built one of my own with a replaceable zener diode and got it to control well now at high speed.
 

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If you don't have enough voltage and amps (VA) out of your 125 CC, then my fix won't work. If you're getting too much, then look at it. The smaller motorcycles, less than 350 CC from my experience didn't have voltage limiters, just rectifiers. They kind of self limited their output switching in the two extra coils as needed when lights were turned on. Either situation could handle when the horn was depressed, brake lights were turned on, etc. They just didn't need that limiting feature. Honda called it a voltage regulator.
 

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Discussion Starter #6 (Edited)
Thanks, I know about it. Existing 6V installation can be improved by for example LED front bulb (much lighter then standard), which consumes 5W instead of 25W in conventional. Reduced power demand gives voltage increase. According FSM I would expect 8,3 V at 10 krpm, even with standard light. For that purpose, I will try to make this module for my bike based on Your conception.
 

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Thanks, I know about it. Existing 6V installation can be improved by for example LED front bulb (much lighter then standard), which consumes 5W instead of 25W in conventional. Reduced power demand gives voltage increase. According FSM I would expect 8,3 V at 10 krpm, even with standard light. For that purpose, I will try to make this module for my bike based on Your conception.
If voltage regulation is a concern, adding a voltage regulator isn't difficult. There are combined 6V regulator/rectifiers, too. I have a few sitting in the shop if you need or want one.
 

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Discussion Starter #8
Thanks, I will check rev/voltage values. If I will decide to implement regulator I will contact You. I would request for shipment to Salt Lake City, UT, where our supplier is located.
 
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