Topic: Dyna S unit - max A, V? Add voltage regulator feeding the unit-NO over voltage

[PeWe]

I have a Dyna S ignition with 5ohms coils.
I have had charging issues (too low V) that I solved by adjusting the regulator. I checked all connectors, measured the alternator coils, rectifier diodes. all according to the manual. The regulator needed service also according to the manual, measuring adjusting gaps, clean points.... Woke up after jumpering the 12V direct to the field coil (black-white), then connected the regulator again after >15V was confirmed.

BUT I do not trust the CB750 electro mechanical regulator. I'm convinced that it can reach >15V which might harm the DYNA unit. Headlight ON is one good limiter right now.
It's very easy to add an electronic regulator component (same size as a 1-3A transistor) feeding the Dyna unit only. These small circuits cost $1-2US. Just connect it direct on the wire with a fuse before it. Hanging design.

- Which voltage is recommended to use? 14V?
- How many amps? Is 1,5A enough?
Note: This is for the Dyna baseplate unit only.
The coils will be fed by the normal voltage regulated by the CB750 regulator. I'm sure they will not become damaged by >15V or are they sensitive too?

The CB750 design with points will not get harmed by >15V except for battery and shorter bulb lifetime, right?

One good thing with Dyna S and 5 ohm coils is the possibility to quickly replace it with points baseplate with its rotor.Just plug in as usual except for the 12V wire.

[PeWe]

update:
I have this charge voltage indicator: http://www.ebay.com.au/itm/190748654357?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
It show green when driving with headlight off (parking light only). Not enough voltage when my H4 headlight is ON. Even when driving  6000 rpm's.
Green is from 13,2V.

I think I need to test the old fashion points again :-)
I drove the bike 1979-1990 with points and H4 headlight always on without any charging issues except once when the battery was weak due to no maintenance wintertime. Headlight suddenly off under 4000rpm which I discovered on a curvy Italian countryside road in the evening.

Check eBay for TEC stuff..... always something to purchase...this will be my third ignition....

[TwoTired]

I have had charging issues (too low V) that I solved by adjusting the regulator.

BUT I do not trust the CB750 electro mechanical regulator. I'm convinced that it can reach >15V

I wouldn't trust it now either as you have adjusted it wrong.

The SOHC4 "voltage regulator" is actually a voltage limiter whose purpose is to protect the battery from being overcharged by over voltage.  ie. sense too high a voltage = diminish alternator output.

The adjustment setting is to limit the peak voltage delivered to the system/battery, because over 15V will damage it.

If the charging system can now deliver more than 15V, you simply adjusted the regulator wrong and likely under the wrong conditions.

The stock lead acid battery is a huge power sink to limit system over voltage until it has been charged to peak capacity.  It will still absorb power beyond that, but it has it's limits.  That limit is generally accepted to be 14.5V -14.7 V, at which time electrolysis occurs, still absorbing power, but using that energy to separate hydrogen and oxygen from the water in the battery acid and heat the electrode plates.

[scottly]

Why not just upgrade the mechanical regulator to a solid state regulator which will protect the whole system? There are lots of inexpensive automotive regulators that will work.