Capacitors are crap for use on these bikes. Get rid of them and use a 14 amp/hr battery that is fully charged, and your problems will all be gone.
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CDI massive voltage drop with headlight on
- Thread starter Hyperballsmcgee
- Start date
Hyperballsmcgee
XS650 Enthusiast
Tevan that works with Hugh has run a sparx capacitor on his xs with a PMA for years with no issues...
Well Gee, McGee,
before you take Tevan's word as the unbiased truth think about where he earns his money, eh?
I'm with the retired gentleman on this, caps are rubbish, use a battery.
Hyperballsmcgee
XS650 Enthusiast
I see where you guys are coming from, I'm just saying that there's plenty of xs with capacitor power and Hugh has always helped me out no questions asked
Have you tried ohming the headlight circuit? As in hooking one lead of a meter to ground, and touching the other to the power side of the headlight switch. Flip the switch to on. Switch to the other on. What ohm readings do you get?
If very low you have a short to ground somewhere.
Leo
If very low you have a short to ground somewhere.
Leo
What you have is a completely different system. Single-phase vs 3-phase, different regulator, different rectifier. The alternator's voltage ripple will be much different. This is one of those occasions where I'd like to put a scope on it...
BigJohnParts
XS650 Member
All the cap does is sorta smooth the ripples out...Sort of like a super low capacity battery, Back in the day, in shop class we used to take Delco condensers (same as used by points era Chevys, Hyster fork lifts with chevy engines and most Harleys) Insert the wire into any 120v wall socket and then ground the condenser body against the screw that holds the outlet cover on....That would charge the condenser up...We'd lay it where we knew someone would pick it up and handle the wire end and case at the same time....Shock the crap put of them...But no amperage to harm them...Your cap is much the same, except the charge and discharge ripple is constant as long as the engine is running...Most set ups using a cap, while running at idle will have the lights dimming and pulsing at the idle speed....You may have more current draw than what the cap can keep up with since it only stores the current for a short time..Whereas a battery is a storage device and puts outs pretty much a constant stream of dc current as long as it has a charge going into it...
Confusing, but not undoable..
John
Confusing, but not undoable..
John
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Hyperballsmcgee
XS650 Enthusiast
I'll also add that when voltage drops with the headlight on the regulator gets HOT... I JUST put this regulator on and haven't been riding so as not to burn it up..
DC Cycle Works
XS650 Addict
Just curious, I may have missed it but what is your charging voltage?
SickBroLife
XS650 Member
I have the same set up as you 81 special only head light and brake light with capacitor, I am wondering if your problem is the precursor to mine. My Regulator/Rectifier gets super hot too, and now is only pumping out 3v and melting the yellow wires. Could he issues be in the compatability with this component?
Hyperballsmcgee
XS650 Enthusiast
charging voltage is 14.5, could someone make a quick diagram explaining wiring caps in series vs in parallel?
The wiring diagrams on page 1, show 2 capacitors wired in parallel. That is the correct way to increase capacitance.
PMA rec/reg units getting super hot and melting wires, suggests to me that the regulator is of a light duty design. As an example, if HHB is buying Taiwan alternators rated at 16 amps, but the regulator is only designed to handle 8 amps, then the regulators are going to get hot and fail. I suggest you ask the HHB people some very specific questions.
For all lads that are trying to run PMA electrical systems, a few suggestions. There is a Search box in the upper right corner of the page.
Type in some words such as ................"PMA hot wires". You will find many posts from the last 5 or 6 years. Similar problems in all of them..................stators with poor insulation, stators getting very hot, stator to rec/reg wires getting very hot and sometimes melting, regulators producing very high voltage, regulators producing very low voltages.
Many excuses are offered......................poor installation by the buyer, a bad batch somehow slipped through quality control, poor or wrong solder was used, etc. etc.
Here's my advice, you can take it or leave it. Stop buying the cheaply made, poor quality kits that are made in Taiwan/China. These kits are being sold by Mikesxs, HHB and other aftermarket sellers. They are of an inferior design of light duty construction. If you want a PMA system, only buy high quality parts that are designed and
made in Japan.
Type in some words such as ................"PMA hot wires". You will find many posts from the last 5 or 6 years. Similar problems in all of them..................stators with poor insulation, stators getting very hot, stator to rec/reg wires getting very hot and sometimes melting, regulators producing very high voltage, regulators producing very low voltages.
Many excuses are offered......................poor installation by the buyer, a bad batch somehow slipped through quality control, poor or wrong solder was used, etc. etc.
Here's my advice, you can take it or leave it. Stop buying the cheaply made, poor quality kits that are made in Taiwan/China. These kits are being sold by Mikesxs, HHB and other aftermarket sellers. They are of an inferior design of light duty construction. If you want a PMA system, only buy high quality parts that are designed and
made in Japan.
Hyperballsmcgee
XS650 Enthusiast
I agree with you on cheaply made parts, however, my system worked great with a battery, only when I installed the capacitor did things go cuckoo. I just picked up a tiny 12v 1.3ah battery about the size of two packs of smokes that I'm going to try. there was an xs650 I believe was on chop cult that ran on a 12v 0.8ah battery and the guy had reported no issues. I'll let everyone know how it works out.
Hyperballsmcgee
XS650 Enthusiast
well... didn't fix it. still same freaking problem. put a battery on it and all seemed good and well. take it out for a ride and voltage goes to the can and regulator starts heating up. I don't get it. everything worked fine with a battery, switch to capacitor and have this mysterious voltage dump, put a battery back on it wired exactly the way I had it before and still have the same issue. I wonder if the capacitor may have killed the stator...
I'm thinking that it may have taken out the regulator. For these kinds of charging systems, there's two types of regulation:
Shunt type - The regulator will dump the alternator's current, producing heat in the rectifiers and stator.
Series type - The regulator will block the alternator's current, producing high voltages in the stator.
The more common type we've seen here is the shunt type.
For more trivia, search on "shunt regulator" and "series regulator"...
Hyperballsmcgee
XS650 Enthusiast
this is a brand new regulator. my first one took a dump after a few weeks...
mrriggs
XS650 Junkie
The regulators are typically not linear regulators which means that they do not vary in resistance to regulate voltage. When the voltage threshold is reached they completely short out the alternator, meaning zero volts out. When the voltage falls below the threshold they "open" and put out the full alternator voltage. So the voltage output from the regulator is not DC but a series of voltage spikes.
When paired with a battery, this scheme works well since a lead-acid battery will easily soak up these spikes and put out a DC current.
The regulators are designed with the assumption that they will be hooked to a battery so little effort is put into output filtering. When you take out the battery the regulator will oscillate. The purpose of a capacitor is to stop that oscillation.
When paired with a battery, this scheme works well since a lead-acid battery will easily soak up these spikes and put out a DC current.
The regulators are designed with the assumption that they will be hooked to a battery so little effort is put into output filtering. When you take out the battery the regulator will oscillate. The purpose of a capacitor is to stop that oscillation.
I tell the lads to stop using capacitors, but they don't want to hear it. They try to use minature batteries, but that also is a bad idea.
Hyperballs.................your first regulator failed after 2 weeks! What is that telling you? HHB is selling you poorly designed and poorly made parts.
If you're determined to use a PMA, then use only Japanese made parts along with a battery, or go back to using a stock alternator system as they are inexpensive and very reliable.
Hyperballs.................your first regulator failed after 2 weeks! What is that telling you? HHB is selling you poorly designed and poorly made parts.
If you're determined to use a PMA, then use only Japanese made parts along with a battery, or go back to using a stock alternator system as they are inexpensive and very reliable.
mrriggs
XS650 Junkie
The capacitor itself isn't to blame. I've been running [trouble free] for 8 years on a tiny little capacitor. A battery is only a solution when the battery works. When was the last time you had a battery go for 8 years without having to touch it? For that matter, when was the last time you had a stock alternator go for 8 years without touching it?
You can't condemn all PMA/capacitor setups because of the poor execution of some.
You can't condemn all PMA/capacitor setups because of the poor execution of some.
