1. Dismiss Notice
  2. Hey Facebook people... We've created a group for XS650.com members to connect. Check it out!
    Dismiss Notice

Nylon screws

Discussion in 'The Garage' started by apox, Mar 1, 2011.

  1. apox

    apox XS650 Addict

    I just installed a pamco in a 1977 motor with 1980 regulator/rectifier combo. Do I need to install the nylon screws with this set up? Because I've heard people say it's only a certain scenario.

  2. littlebill31

    littlebill31 Smells of Raw Fuel

    You need them if your engine is '79 or older. So, yes. You're "un-grounding" the stator.
  3. MN_Bobber

    MN_Bobber 79 XS650 Newb

    What if I'm running a seperate rec / reg in a 78 with the points ignition.

    Are they needed with that combo too?

    Is it a yes, unequivocally, if you have a 79 or older motor?
  4. littlebill31

    littlebill31 Smells of Raw Fuel

    You need the screws in them because the old, separate reg/ rec works after the rotor and the new, combined, solid state reg/rec works before the rotor. I'm almost positive it has nothing to do with the Pamco. It's the regulator and rectifier that matters.
  5. pamcopete

    pamcopete Ride.Enjoy.Life is Simple

    The regulator in the combined reg / rect works the same as the separate regulator, it's just in the same box as the rectifier. However, the combo reg / rect provide a pulsed ground to one rotor brush so the other brush needs battery, whereas the separate regulator provides a pulsed battery to one rotor brush so the other brush is grounded.

    Using Nylon screws allows you to unground the grounded brush in earlier engines so you can apply battery in place of the ground which allows you to use the later combo reg / rect or other aftermarket regulators, such as the Chrysler regulator.
  6. MN_Bobber

    MN_Bobber 79 XS650 Newb

    Thanks guys, makes sense.
  7. apox

    apox XS650 Addict

    Ok so.. My rotor must be from a newer motor because I didn't need the nylon screws.. The brush assembly is all plastic, and the threaded holes for the brush z brackets (my best description) do not contact any screws that dont only contact plastic. Its definitely ungrounded.

    Thanks though
  8. XSLeo

    XSLeo XS650 Guru Top Contributor

    On the wires at the brushes, one wire is green, is the other black or brown? Black is a 79 and earlier, the brown is 80 and later.
  9. apox

    apox XS650 Addict

    It's brown. So my motor is 77 but my rotor is 80. 3G1-XX stamped on it, so that would be 80. That's why I don't need to unground it?
  10. pamcopete

    pamcopete Ride.Enjoy.Life is Simple


    It's not the rotor. It's the stator. The stator has the brush holder. I you have your stock stator ('77) then you will need the nylon screws for either a '80 to '83 reg / rect or the Chrysler regulator. You do not need the nylon screws if you are using the stock separate mechanical (relay) regulator.
  11. apox

    apox XS650 Addict

    Will this picture help?

    it seems ungrounded to me. I took electrical engineering in school, not saying im smart lol but the brushes themselves as well as the screws/threads and the brush holders are all suspended in plastic not touching the sides.. seemed ungrounded to me, can't seem to find a spot that would ground it.


    that pickup has since been removed since I put your pamco ignition on

    Attached Files:

    Last edited: Mar 7, 2011
  12. XSLeo

    XSLeo XS650 Guru Top Contributor

    Thats an 80 and later stator. It has the ungrounded brushes. No need for the nylon screws.
  13. apox

    apox XS650 Addict

    Sweeeeet I knew school was good for something :p

  14. brilamb2

    brilamb2 XS650 Enthusiast

    probably a noob question, but in about to do the chrysler, rs combo,n an 81 (4m4) and wheni check the brushes, they show ground when the bike is off, is this right, or is this why i have no charger?
  15. KharneTheDestroyer

    KharneTheDestroyer XS650 New Member

    I have what appears to be an '80's stator in my '79 special too. I just bought a brand new wiring harness and its all installed, but where (if at all) does the lil magnetic module on the stator hook up? it has a red, a black, and a gray wire. also I've got what I believe to be the combo reg/rec and is wired in using the red, black, and three whites, but I can't figure out where the extra green and brown wires go, I've even tried following some videos on youtube and that doesn't seem to do the trick. any help?
  16. XSLeo

    XSLeo XS650 Guru Top Contributor

    The little magnetic mudule on the stator is the pick ups for the TCI. If you are using the points from the 79 it can be removed.
    If you have a stock combo reg/rec it has the Red, Black, Three Whites, A brown and a greeen wire.
    On your 80 up stator the wires coming up from it are Three Whites, a Brown, A Green a Yellow And a Sky Blue. As far as the alternator goes you only need the three whites, the brown and green wires.
    On your reg/rec the three whites go to the three white on the stator, the red to battery positive, the black to battery negative, the brown to power after the key switch, the green wire to the green wire to the stator.
    The brown wire from the stator goes to power after the key switch. Often peolpe hook the brown wire from the stator to the brown wire from the reg/rec together and run a brown wire from that connection through a fuse and hook it to power after the key switch.
    I like this diagram. If you look it shows the early seperate reg and rec hooked up. It also has a box with the later combo reg/rec. you just swap the box for the early set up.

    Attached Files:

  17. Biddington

    Biddington XS650 Member

    i have a 73 tx 650, i am making a simplified wireing harness, but i am still usuing the stock regulator and rectifyer, i dont need to uses the nylone screws do i? :shrug:

    thanks stephen
  18. apox

    apox XS650 Addict

    The screws are based on rotor stator setup, if it's a 73 I believe you do need the screws.
  19. retiredgentleman

    retiredgentleman XS650 Guru Top Contributor

    Correct...................nylon screws not needed.
  20. apox

    apox XS650 Addict

    Your reg/rec is combo? Or separate?
    Last edited: Aug 8, 2011

Share This Page