WOW! CHECK this OUT for VOLTAGE

ANLAF

ANLAF

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Fellers

My voltmeter arrived all the way from China. Recommended by reviewers on eBay, so who am I to doubt - well, yes, I do doubt, so I got two of the things to double check.

The bike has been running very poorly, progessively worse. Thought it was the carbs. TwoMany said 'Might be the ignition'. I wired in the volmeter and found loose connections at where the two cable from the Boyer ignition link to the wires coming out of the digital box. Started up - but WOW! the voltmeter was reading 15.1v. THen between 14.7-15.1v.

Oh! dear - this isn't what I expected.

I swapped the voltmeter for the second voltmeter that arrived from different supplier, and reading just the same high-up 15.1v.

I'm running a HUGH's PMA and rectifier that he sent last summer.

Battery died on me last month (hmmm! this why?) and on capacitor now. Isn't the regulator supposed to regulate that to c.14.4v? Bike running fine on 575 miles around Wales three weeks ago apart from spluttering over 50 mph. Changed HT leads, seemed to cure it, but progressively worse from then. First, I'm worrried I am damaging stuff (I've downed tools in case the electronic ignition gets it) Second, I want to know what the problem is! Third, I want to fix it.

Any help gratefully received fellers.
 
Do you really trust accurate readings from made in China voltmeters? Those should only be used for ballpark readings while riding. I have one that is actually adjustable, so I can calibrate it with my multimeter.

BTW, do you have a quality multimeter? If not you should, use that for accurate readings.

Spluttering over 50mph? Not sure it's related, could be carbs... Do you have spare coils to rule that out? What carbs/filters, running pleated pods by any chance? To my knowledge over volting a bit is only bad for the battery, at higher levels you might blow headlights. I used to regularly see 15v + on the old POS mechanical regulator and it didn't kill anything. I also have a Boyer.
 
Bikes,cars and trucks are designed to run best with the voltage at 14.1 volts. A good regulator will control voltage around 14.0 to 14.3 volts.

If you are seeing greater than 14.5 volts, then that can cause damage to electronics and lights, and should be avoided. That also leads to low electrolyte level in the battery , if you have a battery.

Your PMA regulator must be having a hard time shunting the extra voltage to ground as heat. Perhaps the PMA regulator is just of poor quality/design and just can't do the job.
You can help the PMA regulator by always keeping the headlight on, and if that does not reduce the voltage, then try using a higher wattage headlight.
 
Shunt regulators are a poor design. I run a series regulator on my versys for the very problem of loaded up stators and shunt regs getting hot as shit, mean short life.

Posted via Mobile
 
Maurice

The voltmeter was recommended by review of good-old eBay. I have a voltmeter. I will use that as a control - but until I know what is going on I am reluctant to start the bike in case I burn something.

I sorted the spluttering over 50mph by swapping the HT leads, but thanks. I am on Boyer ignition, but I have used the multimeter to check the Boyer coil (2.70 ohms springs to mind as checking out as spec). I'm on UBI pods (those pleated pods are a nightmare).

So far nothing has blown or burnt - phew!

Interesting that you got up to 15v without damge.

Thanks for your comments.

ANLAF
 
Well I did not ride for long in that state, that's for sure, the mechanical regulator went to the bin and I'm doing the same on my old CBs.

It would be surprising that the PMA regulator was putting out this kind of voltage (do get a second opinion with your other voltmeter), but you never know. Usually when they go bad voltage drops and they stop charging, that's happened to me a couple times. Bump-starting a VFR in the summer with all gear on is good workout.

Good luck
 
Retiredgentleman

Unless I have put the voltmeter on the circuit in the wrong place (between ignition switch and fusebox) then 15.v is too high for me.

The regulator is part of HUGH's PMA package, so no reason to believe it is of inferior quality, nonetheless it may have failed, even though I got it last summer. Yes, I should check the grounding. It may be, then, that the grounding started as intermittent and has become more so with vibration. Can you help with how to use the multimeter to find a grounding issue in relation to a regulator? The regulator checked out at 4.71 for the three diodoes with the flow, and 0 against the flow, so it is pointing to the grounding.

Yes, I always run with the headlight on once I have started the bike, and I will look at increasing the wattage on the lights, thanks.

Thanks, again,

ANLAF
 
CDNTX650

Thanks for enlightening me - I didn't know that there were differences in regulators.

Does anyone know if HUGH's regulators are shunt or series? Hugh, if you are there, can you let me know?

I have checked images on the internet, and the Hugh's regulator looks very like a series type. I would imagine, then, the old OEM regulator is more likely ot be the shunt type - but I know nothing. Retiredgentleman talks of 'shunting' the excess voltage to ground, so I am open to suggestions.

By the way, I have my regulator bolted to the rear engine bracket (kickstart side) it gets plenty of air.

Thanks for your help.

ANLAF
 
Maurice

I have swapped the voltmeters around, and both the same 15.1v. I will get to the bottom of this - just needs a bit of patience and... ah! a cup of tea and a slice of cake to help me think.

ANLAF
 
Lots of new bikes use pma and shunt regs. I assume hughs is a shunt. A friend just did the stator in his newer honda....burnt...alot of versys riders reported burnt stators at around 30,000 miles, and repeatedly. Those who went with a series reg havent done a stator again.

Posted via Mobile
 
Seems I read about over-charging PMAs all the time around here. They routinely burn out Pamcos and other electrical components. Some improvement over stock, lol.
 
PMA's produce full output at all times. As the engine rpm goes up, the PMA steadily keeps putting out more and more voltage. If the loads cannot take all that is generated, then the regulator trys to direct the extra current through a resistor, and convert the extra current to heat.

The PMA ia similar to having your foot pressing full down on the gas pedal, and then the other foot pushing on the brake pedal to try to control the speed of the vehicle.

The stock alternator is of a better design, as the strength of the rotor's magnetic field can be varied as needed to control the output voltage. The stock alternator only generates as much current/voltage as needed, unlike the PMA that generates full bore all the time.

I'm don't know why this PMA conversion is so common, when the stock alternator works quite well. Perhaps just good "marketing" by the PMA sellers.

All the cars and trucks that I have ever driven, had the electro-magnet rotor type of alternator.

I worked in large power plants for many years, and all of those industrial alternators used electro-magnet rotors with brushes.
 
Retiredgentleman,

I've kept the stock rotor/stator on bike No.2, and I will be running that with electronic ignition. Something to compare. In the meantime I have checked all the ground connections. I am coming to the conclusion the regulator is not doing its job, and perhaps a replacement is needed.

ANLAF
 
Ahh com'on Anlaf you were just carrying on the other day about how you "ripped them wires out" and did your own.
If you got a poor wiring job I think I'd have a talk with the mechanic. I mean we are a disposable society but a wiring job that rides you less than a thousand miles????
The soil there must favor money trees.
 
retiredgentleman said:
PMA's produce full output at all times. As the engine rpm goes up, the PMA steadily keeps putting out more and more voltage. If the loads cannot take all that is generated, then the regulator trys to direct the extra current through a resistor, and convert the extra current to heat.

The PMA ia similar to having your foot pressing full down on the gas pedal, and then the other foot pushing on the brake pedal to try to control the speed of the vehicle.

The stock alternator is of a better design, as the strength of the rotor's magnetic field can be varied as needed to control the output voltage. The stock alternator only generates as much current/voltage as needed, unlike the PMA that generates full bore all the time.

I'm don't know why this PMA conversion is so common, when the stock alternator works quite well. Perhaps just good "marketing" by the PMA sellers.

All the cars and trucks that I have ever driven, had the electro-magnet rotor type of alternator.

I worked in large power plants for many years, and all of those industrial alternators used electro-magnet rotors with brushes.
Click to expand...
Agreed. I have a mikes new not rebuilt(yeah, right ) rotor I put on 3 years ago. Now ,I haven't put on thousands of miles, but I do check my idle current, and charging current frequently. idle, 12.7, revved, 14.5. all the time. Ive got the stock rotor, original reg/rec, my own wiring. rock solid. I think the pma's are a better idea to do away with the black box of the latter bikes. I run the black box, and it is good too, I did peek inside, and found no corrosion, or water damage. My bike was a serious basket case when I got it, but I think it was well kept when it was back together years ago. I would like a pamco , though.
 
Weekendrider,
Yep, did the wiring myself. It's a learn-as-you-go process, so I must have done something to upset the system. I am going to re-route the ground from the regulator to somewhere on the frame close to the unit itself - at the moment I have it joining up with other ground wires and bolting at a central grounding-point under the seat. I did notice that ground point had become dirty and corroded again even in a few months since I lasts tested and cleaned there - it's in the direct line of fire from the elements.

I won't give up, Weekendrider, I will keep going until the only answer has to be a defunkt regulator - I hope it's not, I've just checked out the prices for a replacement, ouch!

ANLAF
 
5twins said:
Seems I read about over-charging PMAs all the time around here. They routinely burn out Pamcos and other electrical components. Some improvement over stock, lol.
Click to expand...

How many of those can be traced to poor wiring or Chinese components?

I put together my PMA in 2007 using genuine Nippon-Denso parts. This bike has been my daily rider (year round) for most of that time and it's still going strong.

You can't condemn the concept as a whole based on the poor execution of some individuals.

I'm actually designing my own regulator/rectifier now. It will be incredibly inefficient and [hopefully] get hotter than hell.
 
I have minimal wiring. Today I checked every connection on the ignition circuit and cleaned the grounding points. So, that's eliminated (fingers crossed) wiring defects. That cheap Chinese voltmeter is still reading... no, it's changed, now it has increased from 14.7-15.1v to 14.8 to 15.4v. Is this a cheap unreliable part...?

I have the multimeter out.

Anyone know where I take the voltage reading? Across the terminals of the battery I took of a few weeks ago the voltage read up to 14.4v running (and that was a battery with a dying cell). Now I run with a SPARX capacitor - so where do I put the multimeter probes on that set-up?

ANLAF
 

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