Pamco ignition break up

Maddog2201

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Hey all,

So I'm having a rather confusing issue at the moment that only arose after installing my Pamco, mind you this was about a year ago, when I first installed it the bike would idle great, the timing was perfect, it idles way better than ever before but was a bit difficult to start, I tried to take it out on the first ride and it wouldn't rev past about 1500 RPM before it'd start to break up, badly, shuddering along with a very rich smelling exhaust (Which I could smell riding the bike) basically not firing. Did some research and we decided it must be battery related, this was further proved when I ran a hot wire directly to my ignition positive and went for a ride with zero issues and the headlight on the entire way.

Since then, I sort of solved the issue by running a wire via a relay directly to my ignition coil with two noise soak capacitors either side of the relay, every now and then, usually after short trips and lots of idling the problem would come up again but after struggling up to 100km/h the problem would be completely gone, no issues, I also haven't used the electric start for the year I've been riding it which helped greatly.

Fast forward to now, I've just got done running thicker wires through my loom as there was 2 volts of drop between the battery and the brown after the ignition, I've replaced the three white wires from the alternator to the regulator (Original regulator, still works within spec, always provided 14.4 volts at 2000 RPM even before replacing the wires, now provides it at about 1500 RPM), the green power wire from the regulator to the alternator rotor winding, the entire earth has been replaced with way overkill 25 amp wire as well as the main positive and the brown wire, I've connected the headlight up through a relay directly to the battery which has resulted in it being white instead of deep orange like it used to be.

After all that, it still spluttered on me today, this morning very mildly and as expected it went away after I hit 100km/h, but this afternoon I couldn't shake it, I checked my charging and it's good, but the battery's sitting at 12.1v's, that's according to a cheap multi metre, the strangest thing was that the indicator dash light would flicker everytime the bike spluttered and surged. I don't have my indicators wired up stock, I have a 3 wire flasher can with power, output and dash out (Rewired to suit it).

The only thing I can think of is that the earth for that wire is dropping below 0v somehow. Is there any need for the noise capacitors around the relay? Could they be the cause?


Sorry for the novel, just wanted to lay EVERYTHING out.
 
I think I've narrowed it down to either rich mixture or a regulator issue. I installed a voltmeter so I could see what it was doing while I was riding, it sputtered as it hit 15 volts. Likely has something to do with the issue. Anyone know what the max voltage is for the e-advancer?
 
The E-Advancer is good to at least 18 Volts. The sputtering at 15 Volts may have something to do with the engine speed when it hits 15 Volts or the regulator is producing electrical "noise" as it switches on and off rapidly to control the voltage.If the regulator is the original crappy relay type, then toss it and get a solid state regulator.
 
You shouldn't be hitting 15 volts, just low to mid 14's at most. I agree with Pete, replace that "antique" mechanical regulator. Although many last darn near forever, yours appears to no longer be doing it's job properly. But, even when they do limit the output properly, their regulation of that output is very poor. The alternator output will bounce up, down, all over the place, even at higher RPMs when it should be steady near the max. I think the vibration causes this, shaking those mechanical contacts inside the regulator all around.

We're lucky in that we can use low cost, high quality automotive regulators on these. In the case of the '79 and older alternator, a VR115 or it's equivalent works well.
 
I've been looking to upgrade the regulator, but in doing some reading the stock regulator is spec'd to produce between 14.8 and 15 volts at above 2500RPM. Seems to high to me and is dangerous now that I'm running an AGM. It is matching numbers to my bike though, which is cool. I'll definitely keep it when I upgrade. Mines a 74 so the VR115 should work. Already been burned on a reg/rec from mikes.

Since all this though, I've concluded that it must've been a mixture issue, I backed down my idle circuit after pulling a spark plug and seeing one plug black and fluffy, hasn't done it as bad since, but I'm overly concerned about when it gets hot now. I originally richened the idle circuit because it overheated and ran over after I hit the kill switch. Queensland summers and traffic lights will do that though.

Pete, my tacho's dead at the moment, it was around 5000 RPM when it spluttered though, according to my ear-crometre that is, but since I adjusted my mixtures it's been better.

Is the pamco known to be more sensitive to mixture? This all started the moment I put it in, it'd run fine with this mixture with the points, wouldn't splutter that is.

That said, I've still got no idea why the indicator dash light would flick on when it'd sputter.

Thanks for everyone's input, I kind of feel like I wasted your time.
 
I know the older manuals state the voltage output as 14.5 to 15 but it's commonly accepted today that mid 14's at most is better or best. You do know you can adjust your old mechanical regulator? I would turn it down a little bit and see if that helps.
 
I am aware, but I also don't want to touch it because I have a habit of over fiddling. Got a VR115 on the way at the moment, I'll wire it in and she'll be right hopefully, for now I'm just riding with the headlight on to keep the voltage at max 14.8v.

That said though, sputtered tonight on the way home, didn't this morning or this arvo when I was riding it to uni, I'm pretty much sold on mixture being the issue, and it smelled rich while I was idling in the driveway, but I'm going to check my coil again to be sure, last I checked it it seemed to have a low resistance from plug to plug. With the 5K caps it was sitting at 25000, seems low to me. Haven't tested across the main winding, and to ground from the secondary is fine.
 
Thanks for helping naive young me.

Some important Info that I failed to share all those years ago, I've been getting a real weak yellow spark from the unit this entire time, since I installed the unit in 2017.

Secondary resistance is 16K ohms lead to lead without the 5K caps at each end, and I've since realised that smelling rich could also be the result of it not burning fuel till the second combustion stroke.

The 5K caps are reading about 4.5-4.7K ohms, so I'd say close enough, and I'm running B8ES plugs. I haven't tried a step hotter, though maybe I should before changing the coil over. Weak spark though, and using an inline neon bulb you could see it breaking up at 4K RPM.

I'm going to replace the coil, I'm using Mikes XS part number 17-6822 at the moment, going to replace it with the Harley Part number listed in another post on here by Pete.

Thanks for all the help blokes, I'll update this when I've got more information for more people who are still learning like me.
 
Have you ever changed the alternator brushes? My Pamco equipped bike a reliable runner started breaking up at 4K half way through an iron butt run, it also showed intermittent voltage on a digital voltmeter around that RPM. I completed the ride, replaced the worn brushes when I got home and have ridden it thousands of miles since with no issues. I suspect a slightly out of true rotor contributed to the 4K break up. Bike has a solid state regulator.
Yes the that coil sounds weak and that part number from Mikes has been NOTORIOUSLY failure prone, I've had a primary terminal fall off one brand new from the box! Wouldn't be surprised if one primary lead is hanging on by no more than a thread.
PS Use the recommended plug, BP7ES, that B8ES plugs is too cold AND does not have an extended tip so tends to shield the spark. So be SURE you get that exact number BP7ES. Yamaha originally spec'd the B8ES but later changed the spec to the BP7ES for ALL YEARS AND MODELS in a service bulletin!
 
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Hi
Not read it all

Im also there " is the original crappy relay type, then toss it and get a solid state regulator. "

Then I am up to 4 or 5 bikes last 6 months having their ignition issue at Weak ground or No ground at all ..

No matter what will happen with the installed Ignition Pamco or Other Ignition the wiring must be worked over.
Some grinding at connections carborundum paper and thereafter copper grease .Perhaps replacing ground to battery and / or
Draw one or more extra ground wires .
It can of course in theory be coils and ignition unit Switches .is . Common
Kill switch Rubber grommet in headlamp Fuse holders .. Please Inspect
But better service the wiring to ignition and ground first .Which is something that needs to be done after the wallet is empty if it is the usual problems.
There is some words about capacitor .Perhaps is a solution to something but my first assumption is that they are not needed.
Read the Pamco installation Manual and keep it simple . and check those connectors Again with extra care for the ground wires.
The Yellowish spark indicates a somewhat weak one and then of course it might smell unburnt fuel .
But i Would guess machine is missing altogether at some times My feeling is that a weak spark is still a spark
And would not hinder revving over a fixed value.

Pictures / What bike model year / Wiring if not stock .I think given the competence here ..Within a week this is solved.
 
Have you ever changed the alternator brushes? My Pamco equipped bike a reliable runner started breaking up at 4K half way through an iron butt run, it also showed intermittent voltage on a digital voltmeter around that RPM. I completed the ride, replaced the worn brushes when I got home and have ridden it thousands of miles since with no issues. I suspect a slightly out of true rotor contributed to the 4K break up. Bike has a solid state regulator.
Yes the that coil sounds weak and that part number from Mikes has been NOTORIOUSLY failure prone, I've had a primary terminal fall off one brand new from the box! Wouldn't be surprised if one primary lead is hanging on by no more than a thread.
PS Use the recommended plug, BP7ES, that B8ES plugs is too cold AND does not have an extended tip so tends to shield the spark. So be SURE you get that exact number BP7ES. Yamaha originally spec'd the B8ES but later changed the spec to the BP7ES for ALL YEARS AND MODELS in a service bulletin!


Oh, I haven't changed the brushes, and the slip rings look pretty aged as well, I'll give them a lot tomorrow after work. Excellent thought, I'll check the voltage at that RPM, though last time I did I remember it being alright right up to 5K when it'd rev there. I'll shoot to my local Supercheap and change to those plugs too, cheers.

Jan, Bike is a 74 TX650A, really solid bike, been riding it for 3 years pretty much as a daily through all the issues, it's still gotten me to uni, work, and home, and also to my parents 200K's away, so all in all not bad, just not comfortable.

Wiring should be good, I'm doing electrical engineering, I wire caravan 12v power systems for work, have a cert II in Automotive Electrical and I re built the entire loom from scratch, including adding relays for ignition, headlight on off and high/low switching, which solved a lot of voltage drop issues.

The noise caps are supposed to stop any arcing across the ignition relay contacts, though I'm starting to wonder if they're causing issues instead of solving them. Might replace them with reversed high current diodes instead, see what happens, that way any high voltage induced by the primary collapsing after the power is cut from the primary will just back feed across the diode.
 
I have not used these on a regular rider but Pete swore they were good for 2 horsepower and probably are bit more foul resistant.
BPR7EIX platinum tip, and pricey for a spark plug, but the cost per HP is low. :sneaky:
Not always mentioned is that only one of the two plugs on a dual tower coil gets any use from the platinum tip, the other plug's spark jumps from the opposite direction so the normal not platinum side electrode gets the wear. swap sides on annual plug checks? LOL
Or you could use TWO single tower coils both would spark in the same direction.
There's a trick I have never tried to check spark direction using a #2 pencil.
 
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See if I get this right
You have a Motorcycle not running properly since 2018
With a wiring unknown to us . ( Relays , Capacitor )
A Motorcycle we with stock wiring and installation according to manual some communication
would have sorted out within a week .
Perhaps there is a more valuable lesson to be learned
Pamco Pete is the Manufacturer of the ignition giving advice.
JIM / 5T / Gary / Grizid / Jetmech and others are world class experienced persons ..
Above World Class --- Guru Class
 
You may have trouble finding the standard NGK BP7ES plugs now because they have stopped making them. They only make the BPR7ES now which is the resistor version. If you go with that, you will want to change your resistor plug caps to non-resistor ones. You only want one instance of resistance in the path from coil to plug. That can be either the plug, wire, or cap, but not any combination of more than one. NGK makes a very nice non-resistor plug cap, the LZFH .....

yg3iLp9.jpg
 
I was looking at trying to run my original coils, but the resistance when they're in parallel is too low, and way too high in series, not worth the risk honestly.

Good to know I can get the r variant, I still have the non resistor caps from my old coils, so I'll wack those on, should be a go.

I'm pretty confident in my wiring abilities, that's the one aspect of this that I'm sure is good, I did it all myself and it's neat, I'm going to go through it all again anyway, just to be sure, because I'd hate for my pride to be the reason my bike doesn't run properly.

Plugs, ignition coils and a refresh on the wiring and I should be golden I think. I'll let you know, bike will be running by the weekend I can assure you that
 
You know where to find us Young man
I'd hate for my pride to be the reason my bike doesn't run properly.

Not having seen the actual wiring ...at this point in time I would be very surprised
If you don't mid next week have a couple of relays and capacitors left over on the desk . workbench..
I don't know Pamco but there is most likely a small computer inside ..Small signals .. AD signal treating trigging
Magnetic field can affect ...Perhaps you are expert ..
But that small sensitive computer installation is developed for the environment in the bike
Without extra components
 
All a relay is doing is ensuring proper voltage to the coils, that's why they run them in all modern vehicles, lack of voltage won't be the issue I don't think, because before I rebuilt the loom the bike wouldn't rev over 1500 before breaking up, but it also had 2v of drop.

I dislike the term expert, everyone has something to learn, some are just more experienced than others
 
Alrighty mighty helpful folks.

I've gone and gotten a pair of Bosch WR6DC+, which are listed as an equivalent to BPR7ES, because my local had literally nothing in the BPR or 7 range of NGK, but I know it's actually a stage Hotter plug than the 7ES, also has a resistor, so I swapped to my resistor-less caps from my original ignition system, no other changes and I'm getting a nice white spark when cold, bluish white when hot.

When I first took the bike out for a run tonight I was able to accelerate up to 5K smoothly and strongly, all the way up, quick shift and all, felt awesome, sounded good, as I rode more though, the gremlin started to creep in, so I'm thinking now it's either Mixture's too rich, leaning out, I'm fouling the plugs idling at lights, or the coil is breaking down under heat.

Plug readings for those that are interested:

Right:

Bronze tip, half black and bronze ring, greyish electrode.

left:

Bronze Tip, bronze ring, Greyish black elecrtode.

readings were taken after a maybe 5K ride, including a few pulls from 0-100Km/h, going through and shifting at about 5500RPM, idling at lights, and a short run at 110Km/h.

On acceleration towards the end of the run it was jerking and hesitating again only mildly, but once it pulled past it it was gone in the next gear interestingly enough. By mildly I mean it'd jerk once then carry on. Like a misfire then it's all back on track.

More testing to come.

Next I'll be disconnecting the Condensors and taking it for a ride again, same plugs. Trying to change only one thing at a time if possible.
 
All a relay is doing is ensuring proper voltage to the coils, that's why they run them in all modern vehicles, lack of voltage won't be the issue I don't think, because before I rebuilt the loom the bike wouldn't rev over 1500 before breaking up, but it also had 2v of drop.

I dislike the term expert, everyone has something to learn, some are just more experienced than others

I think you should consider the possibility of the Regulator ( Which has been recommended replacing ) and Relays inducing voltage and current fluctuations .. as well as Magnetic fields that a Controller in the Pamco might not be able to cope with ..
EMC Compability
https://en.wikipedia.org/wiki/Electromagnetic_compatibility

It is not a good thing having ignition spikes at a high revving engine . to soon
That is the reason I stopped trying to develop my own ignition An ignition pulse to soon or a few .. might be enough and one might trash the engine Mechanically in some cases on some type of vehicles.
And then you are a bus Passenger for a while. With much bigger problems.

Now i Read that the Condenser is going out of the bike onto the workbench lol .Soon we hear about the relays also i guess hihihi..
Please don't mess with the mixture at this point in time .Making the bus fare even closer. If you lean it out and get it wrong
 
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