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Pamco ignition break up

Discussion in 'The Garage' started by Maddog2201, Apr 16, 2018.

  1. Maddog2201

    Maddog2201 XS650 Member

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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.
     
  2. Maddog2201

    Maddog2201 XS650 Member

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    Other than this weird one, the pamco's great, I don't at all think it's the problem.
     
  3. Maddog2201

    Maddog2201 XS650 Member

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    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?
     
  4. pamcopete

    pamcopete Ride.Enjoy.Life is Simple

    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.
     
    Maddog2201 likes this.
  5. 5twins

    5twins XS650 Guru Top Contributor

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    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.
     
  6. Maddog2201

    Maddog2201 XS650 Member

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    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.
     
  7. 5twins

    5twins XS650 Guru Top Contributor

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    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.
     
  8. Maddog2201

    Maddog2201 XS650 Member

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    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.
     

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