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Hughs PMA Regulator Overheating?

Discussion in 'The Garage' started by trainwreck13, Oct 3, 2011.

  1. For the past few years I've been running my voltage regulator under the engine in the space where the starter used to be without any problems. About a month ago I bought Hughs PMA kit and a Accel capacitor and swapped everything out. For the first three weeks everthing worked great until one day the bike decided that it only wanted to idle and would completely break up if any throttle was applied. I hooked a volt meter to the capacitor and was reading around 12v at idle and around 5v when I tried to apply throttle. I then swapped the capacitor with a battery and the readings were 13v at idle and 11v at throttle. The readings poined to a fault with the regulator. I then ordered a new regulator from Hugh and installed it. This time around I made it about 10 miles before having the same problem. After letting the bike cool off for about 45 minutes I started it up and it ran fine but once it got warmed up the ignition started breaking up again under load.

    So my questions are, is anyone else experiencing problems similar to this? Is it possible that the regulators that Hugh is selling are that sensitive to temperature? And once the regulator starts faulting does that mean that it is failing and junk or that it is just overheating and once cool it's as good as new?

  2. Punkskalar

    Punkskalar Hugh's HandBuilt

    That points to a Bad Capacitor, if you swapped in a battery and everything is working as it should. 11V is a bit low under throttle, but that could be due to a number of things such as bad wiring, a ground that is loose somewhere, etc... Your Regulator should be fine mounted where it is. They usually overheat from overcharging, not undercharging.

    If you are running that Capacitor at 5V all the time, then you have a wiring issue/capacitor issue. I would double check ALL of your 3 phase connections (yellow wires) are getting continuity. It may be a case that you are getting a decent connection at idle, but as the bike revs up you get vibes that may cause you to have an intermittent connection in one of the yellow wires. Thats just about the only time someone has issues with the PMA swap charging that low...

    Let us know what you find...
  3. With the battery connected in place of the capacitor everything was definately not working as it should. 13v at idle and 11v over 2000rpm would drain the battery under normal riding conditions. When I first installed the PMA system I was getting 11-12v at idle and 14.5v over 2000rpms.

    The bike will not operate at 5v. Like I said in my first post when it acts up it puts out around 12v at idle and when throttle is applied the voltage drops to around 5v and the engine only pops out of the pipes. It will not fire hot enough to bring the rpms up past idle.

    All the wiring is new and the system was working properly when installed. This bike gets ridden at least 70 miles a day on the interstate and was running completely fine until it cut out last week. I will check the wiring yet again though to make sure I didn't miss anything.

    When I first hooked everything up I had a bad connection and basically one of the AC wires was disconnected. The bike ran fine with throttle applied but wouldn't idle which is the opposite of the problem I'm having now. That's why I believe it is something goin on with the regulator. Buttt that wouldn't be the first time I have been completely wrong about an electrical issue...

    How should the AC wires read? Continuity between all the wires and no continuity between the wires and ground?
  4. Punkskalar

    Punkskalar Hugh's HandBuilt

    Sounds like poor wiring, you should NEVER unplug any of the yellow leads while the bike is running. Double check all your connections, and if needed, check this:

    Detailed Technical Information:
    Resistance between the YELLOW leads: 0.7-1.0 Ω.
    Between any YELLOW lead and GROUND: Open Circuit (OL on display)

    If the regulator were bad, you would likely be getting more than 14 volts out of it, if not getting enough, it is usually the stator.

    Also, make sure you are grounded well, and what are you using for a battery or capacitor? Test voltage at the leads coming from the regulator, and then try a known good battery (12V, fully charged) even if you have to run jumpers to hook it in. Lots of people are using poor batteries or capacitors..

  5. pamcopete

    pamcopete Ride.Enjoy.Life is Simple


    Small point here, if I may. Was your previous regulator just a regulator or was it a combined regulator / rectifier? It's not the regulator that generates the heat, it's the rectifier, and I believe that Hugh's is a combined regulator / rectifier so it will produce more heat than a regulator alone.
  6. Hugh,

    As I stated in the first post, I am using an Accel battery eliminator. The battery that I used to see if the capacitor was the culprit is a 12v 0.8amp SLA battery.


    I was previously running a seven wire solid state rec/reg from mikesxs.

    I'm drawing a blank on this one. I really hope that there is a bad connection somewhere that I just haven't found yet because if it's not I might just park the xs in the corner and get my shovelhead finished up and on the road...
  7. Ok I quadruple checked my wiring and couldn't find any problems whatsoever. So I checked resitance on the AC leads and got between 0.6 and 0.8 ohms. Is this satisfactory?

    I'm running a 30amp HD circuit breaker between the positive from the regulator and the ignition switch and thought that may be heating up and faulting so I jumped it with no change.

    Hugh, what do you mean by "Test voltage at the leads coming from the regulator"?

    The wiring on the bike is pretty much as simple as it can be. All I have is the PMA charging system, points ignition and the lights running through a three position key switch. The charging system is running through the 30amp breaker and the ignition is running through a kill switch.

    Any ideas???

  8. Punkskalar

    Punkskalar Hugh's HandBuilt

    "Test Voltage At The Leads" means to check for voltage BEFORE the fuse/breaker panel. Before it connects to your battery/capacitor as well. Basically, right out of the regulator itself before any other external source can affect the system.

    With those readings, the stator is showing good. This might be a total pain the butt, but isolate the ignition from the charging system (run it off of a seperate battery) and disconnect all of your lights and see if the charging system is still acting up. 90% of the issues with this swap come from poor connections, or something else causing a drain on the system that is un-accounted for. Not trying to 2nd guess your wiring job, but you would be surprised how often a wire might chafe and cause and issue(happens to the best of us, even me...)

    Do those tests, and if it is still getting poor output, we'll get you set up with some new parts. I doubt that the regulator is the issue, so lets do these tests just to make sure. I've never had one of the regulators I sell fail other than when someone mounts them in a "fake oil can" or something where they don't get any flow... Well, 1 guy did have his fall off and run it over, but thats another story :)

    I did have 2 Electrosport stators fail right out of the box, but you should have the improved stator that I have been selling for a good while. And, you said that the system has worked for a good while and now has started acting up, so I tend to think it may be an external problem from the charging system. Again, that test shows the stator to be operating properly. Also, double check that the rotor isn't loose on the crankshaft. It happens rarely, but I have had customers not properly torque the flywheel on and it would just spin on the shaft.

    Either way, once I know the test results, I'll be happy to send you out a new stator and regulator if needed... Lets get you back on the road...
  9. Thanks for all your help Hugh.

    I can easily run the ignition off of a battery and take reading straight from the positive and negative leads of the regulator. The only problem is that the issue is intermittent and it only seems to act up when the bike is hot. I'll ride it around a bit tonight and see if I can get it to fault and then get a reading straight from the regulator. You want a reading with only the alternator and regulator in the circuit, is that correct?
  10. Ok here's where I'm at. Last night I fired up the bike cold with the new regulator and it ran fine so I hooked up the other regulator (that I thought was fried) and it also worked fine. I hooked the new regulator back up, since it was already mounted on the bike and took it for a ride around the block to get the engine hot. No issues on the test ride so when I got back I let the bike idle for few minutes and then it started acting up again. Voltage dropped off under load so the bike would basically only idle.

    I then hot wired the ignition to a battery and disconnected the regulator from the rest of the bikes wiring so that it was only connected to the stator. At idle the regulator was reading between 8v and 13v, averaging 10v. When I opened the throttle up above 2000rpms the voltage dropped to 1.0v-1.3v. I then wired in the original regulator with the same results.

    Hugh you were right about the regulator(s) not being the problem.

    The only source of the problem that I can see now is the rotor or stator. But when I checked resistance on the AC wires I got readings of 0.8 ohms between all of them and no continuity to ground. I haven't removed the rotor to take a look at the stator yet (because I don't have a puller to get the banshee rotor off) but if the leads are reading correctly then shouldn't the stator be working correctly?
  11. Any idea what could be going on here?

  12. Punkskalar

    Punkskalar Hugh's HandBuilt

    Sounds like you need to pull that rotor off, and see if it is making contact with the stator at any point, or if any of the hardware is coming loose.

    I'm out of vacation right now, but I'll do my best to stay tuned. Get a puller and see what is going on. I had another customer with similar issues a few months back, turns out the hardware had backed off and was causing the stator to lightly rub on the flywheel. Blue Locktite is your friend :)

    But do keep us posted, sorry for the delayed response.

  13. Ok so I pulled myself away from the shovelhead long enough to buy a rotor puller and drag the xs out of the corner. I pulled off the rotor expecting (hoping) to see something wrong but everything looked fine. I took the stator off and triple checked the wiring for damage and rechecked all the all the hardware, all of which was already loctited and tight. I then put everything back together and fired it up with my fingers crossed but as soon as it had run for about 10 minutes and got hot the problem reared its ugly head again.

    Where do I go from here???
  14. XSLeo

    XSLeo XS650 Guru Top Contributor

    When you checked the stator ohms, you did it cold?
    When you get the bike warmed up and things go bad, stop right there and check the stator ohms hot. They may be changing as it gets hot.
    This may indicate a bad stator. As it warms up and expands a short may happen that won't happen cold.
    I have a stock rotor that changes as it warms up and the charge voltage drops after it gets warm.
  15. Robhall

    Robhall XS650 Addict

    Any resolution on this? I did the PMA swap a month or two ago and just did the Pamco swap with the ultimate coil and mine just started doing the exact same thing the other day. It started out only running right with the headlight off. I was running a 12v 1.3ah battery. Yesterday I checked the voltage which was low so I threw in a 12v 0.8ah battery I had in and it ran great for the day. Later last night I went out and it was doing the same thing again. Today I took it to work and it would only run right with the headlight on... And it was still a bit off. It seems to do alright if the RPMs are kept low. I tested my stator, and got 0.7 ohms between all the leads and it was open when tested to ground (motor). I did notice the terminals in the stator plug were dirty, so I cleaned them up with some sandpaper and a shot of contact cleaner then I took it around the block. This time it ran fine with the headlight off, but would barely run with it on. I tested voltage on the battery as well:
    Bike off: 10.08
    On/headlight off: 11.4-12 idle and 8.4-9 revving
    On/headlight on: 6.5-7.5 idle and 7.3-12.1 revving

    I'm about stumped.
  16. Robhall

    Robhall XS650 Addict

    Good advice. I just checked it hot and got the exact same readings. And all my wiring seems to be good.
  17. When I did all the checks back on october 5th I don't remember how long it was after I shut the the bike off before I did the stator check. I believe the stator is the issue because every other component is testing fine. When I was getting the jacked up readings the only part of the charging system that was connected was the the stator/rotor and regulator and I tried two different regulators with the same results. Tomorrow I'll get it warmed up again till it starts faulting and then do the stator check again. I really don't know what else it could be since I believe I eliminated all other possibilities.
  18. Robhall

    Robhall XS650 Addict

    Still nothing, I double checked the grounds and even cleaned up the terminals and nothing. From the green wire I've got the negative battery wire and another running to the upper motor mount for a frame ground. Is this right?
  19. Green wire from regulator to ground and negative battery to ground, that sounds right.

    I didn't get a chance to check the stator hot yet but I'm pretty convinced that it is the problem. I'll try to check it tonight though.

    Hugh, do you have new stators in stock? How much do they run?
  20. Robhall

    Robhall XS650 Addict

    Well I haven't tried running the ignition separate, but I did just pull my flywheel to take a look. I don't see any broken wires or anything and all the fasteners were tight. What should I be looking for?
    And here are some pics:





    I'm not sure if this is wear or what, but if it is, it's nor rubbing the windings.


    Unless this is wear and it's touching the inside part of the outer stator, but I doubt that little speck of rust would be there is that was the case.



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