KTM 620 rebuild/refresh

Discussion in 'Thumpers' started by gravityisnotmyfriend, Feb 28, 2013.

  1. Young-Gun

    Young-Gun KTM Tragic

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    :rofl

    :clap
    #41
  2. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    Well, the bike is done. I had a couple of hours free on Saturday. I was going to clean her up, but it was just too nice of a day. I had to ride! I went on a short little 30 mile loop and found that if I pushed her hard, the temp light would come on. But, if I took it easy it'd eventually go back off. So, I cut my ride short and headed home. Once I let the bike cool off, I checked the coolant level. I guess I left more air in the system than I thought as it was pretty low. So, I topped her off and headed out again. Put about 50 miles on exploring backroads. Everything worked like it should.

    The ride is oh so nice with the new shock. And riding at highway speeds is perfectly comfortable now that I've got the slack out of the steering stem. I put the Coleman ATV seat pad on her and it pretty much eliminated the vibrations in my seat. Still get a little in my feet, but it's definitely tolerable.

    I didn't take any pictures - I'd say it's because I didn't wash the bike, but the truth is I forgot my camera. I did try mounting my GoPro to the handlebars. It worked - but it picks up a lot of vibration.
    #42
  3. bmwktmbill

    bmwktmbill Traveler

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    Congrads!

    bill
    #43
  4. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    The project appears to be never ending! After I got back from my last ride, I noticed my low beams weren't working. So, I checked my high beams and they did. So, I got a new bulb and installed it. Just went for a ride a few minutes ago and when I got back, my low beam was burned out again. So, I put it on my high beam again and it worked. On a hunch, I blipped the throttle. The high beam went bright white very briefly and blew out. That's when I noticed that all of the indicator lights- the ones that I had a bitch of a time sourcing - were also burned out.

    Well, fuck. That's a high cost - usage ratio. So in addition to replacing all the brand new bulbs I just replaced, I'm also looking at replacing the voltage regulator and/or the capacitor. The service manual indicates that the voltage regulator won't work without the capacitor working. I'm not sure how that's possible as I though that the capacitor worked to just filter out spikes in the voltage. Regardless, I'm going to check it.

    I've done a bit of searching, but have only found threads asking how big of lights they can put on these bikes. Anyone know what the VAC and Amps the alternator puts out? I've got a spare regulator/rectifier that will regulate 100 volts AC and 100 amps down to 12 VDC - well it actually stops it at around 13.8-14.1VDC, but as long as the alternator output isn't too high, I should be able to use it. It's a modern solid state unit, I'm not sure if it's any better than what was available in '94 or not - but the original regulator is no longer available from KTM.
    #44
  5. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    So, I'm baffled here. My best guess is that the voltage regulator has already gone out on this bike once, and that the one that is now bad is not the original.

    I"ve looked at the wiring diagrams and none seem to be exactly like mine. There's 5 wires going in/out of the regulator. All the wiring diagrams I've looked at have 4 wires on the regulator - 2 AC in, 1 DC out and a ground. There is one case where the regulator has 5 wires, but, in that case, there is a diode in line between the regulator and capacitor, but that's not the case here as if there were a diode, it would be attached to the outside of the regulator.

    Also, the wires coming from the generator look wrong. On the bike side, there's one blue wire going to one terminal in the plug and two yellow wires going to the other terminal. That has two yellow (maybe orange) wires plugged into it without a plug. Sorry about the blurry pic, but you can see the colors:
    [​IMG]

    Here's the one I took off my bike:
    [​IMG]

    Now, to me, the wires look like black(1), yellow(2), red(3), yellow(4), green(5). Of course, I'm red/green colorblind, So I'll call em 1, 2, 3, 4, 5. Wires, 2 & 4 are inputs from the generator. And, they produce 40-60 VAC while the bike running. wire #3 goes to the positive side of the Capacitor, and wire 5 goes to the negative side of the capacitor, as well as being split and grounded to the case of the regulator.
    [​IMG]

    Then there's wire #1. I'm holding it in the index finger of my hand in the previous pic. No idea where that one goes or what it does. It's not a ground. And, if it was supposed to be, it's not grounded any more.

    What I do know is that I can put 12VDC to the positive and negative terminals on the capacitor, and that powers all the lights on the bike.So, I don't think it's another power wire. And, there's no resistance between it and either of the other two generator wires, so I don't think it goes to the generator.

    So, here's why I'm baffled. I tried hooking up my other regulator/rectifier. It's brand new, but I guess I've never actually checked to see if it works. But, when I hook it up, I get -2.63 VDC between the power wire and the ground.

    Any guesses as to what the #1 wire is or where it's going? How about my weird voltage output? Any guesses there?

    I did find a replacement regulator rectifier that is supposed to be a replacement for the discontinued stock item, but I fear I'll just end up dropping $150 on another part to find out it doesn't fix the problem.

    Also, what exactly does the capacitor do? I'm assuming it's just a filter to keep the lights from flickering based on the RPM of the bike. What would happen if it were removed? Can the electrical system work without it? Any reason not to just eliminate it? I tried my new regulator wire with and without the capacitor - didn't make a difference.
    #45
  6. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    I may have figured something out. The wiring diagram for a '97 620 looks like this:
    [​IMG]


    The interesting thing is that the wiring in that diagram closely matches what I"m seeing. It's got the blue and yellow wires coming from the generator changing to just yellow wires at the plug. It's also got 5 wires and they are mostly the same color - except mines got a black wire where the diagram shows brown.

    So, here's the very interesting thing. it has the black as ground and both the red and green going to the positive side of the capacitor.

    I'm thinking it's possible that I simply plugged the wires back in incorrectly when I put the bike back together.

    It's worth a try, I guess.
    #46
  7. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    #47
  8. Mow-ree

    Mow-ree Been here awhile

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    Well I can tell ya that you were right on the color of the red n green wires, and thats about all I can tell ya!
    #48
  9. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    Well, at least I got something right!

    I did some research on the honda RR that I took off the bike. Green is ground. Still don't know what black is. So, it looks like stuck just buying a new one. I did find a new OEM RR from cheapcycleparts.com. Seems abit steep - but at least it's free shipping:

    [​IMG]
    #49
  10. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    Anyone have experience with Baja Designs? They've got a RR for my bike for 1/4 of the OEM. I'm very tempted to just order one.
    #50
  11. Seikkailu_R

    Seikkailu_R Been here awhile

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    Maybe this helps with that black wire?

    And some stories what that style system can cause if connections are poor.
    #51
  12. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    That does help - I think. So, I'm going to guess that since my bike doesn't need a signal wire - that black one is wired directly to the positive terminal on the battery. That I can check.

    Thanks for the link. I may be one step closer to getting this figured out.
    #52
  13. Seikkailu_R

    Seikkailu_R Been here awhile

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    Bike dosnt need that wire, but RR needs it to be connectet to positive to work correct.
    Directly to positive is ok for testing, but if i remember right it is recommended to connect that sensing wire to switched positive?
    +12v feed to CDI box is near, and powered allways when ignition is on.
    #53
  14. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    I got my regulator from Baja Designs in and installed on Tuesday. The only light I could test was the High Beam on my first headlight since all the other filaments were fried by my old RR. It works!

    I got a new headlight and taillight installed late last night, but of course it is raining today, so the bike has to sit in the garage. Hopefully I'll be commuting in on her tomorrow.

    Hopefully, this project is finally done.

    Well, once I replace the turn signal and instrument panel bulbs, that is!
    #54
  15. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    I just learned a painful lesson. If you are going to buy a universal regulator, it would be wise to call the company and find out if it does indeed work with your bike.

    I put it on and it does work at idle. But, if I rev the bike it doesn't work anymore. I called Baja Designs and was informed that it won't work with my bike and that I am frying the RR by using it. So, I'm just out the money since they aren't interested in having me return it.

    Fuck.

    I've got no one to be pissed at but me. So, I'm out the money for the RR and still have to find one that will work.

    Fuck.

    I was planning on riding this weekend. Looks like my plans may have to change. I guess I could trailer it to an ORV park and ride off road.

    Just sucks.

    Anyone got a line on a RR that will work for my bike? Also, does anyone know why the Baja Designs one won't work? The guy I talked to said something about it being both an AC and DC generator. I've never heard of such a thing. It's putting out 30-60 VAC depending on engine RPM. I guess I never tried to read DC voltage.


    Man, I wish Creeper hadn't disappeared from here. I could real use some expertise about now!
    #55
  16. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    Did some digging. My KTM has a 3 phase generator. The RR I bought is only for a single phase generator. So, it's likelyu fried. I did find a RR for my bike. But, it's used and expensive. But, it could be one of the last ones available out there. I guess she'll be an off road only bike until I get this issue figured out.

    I just can't believe that there isn't a regulator/rectifier out there that will work with a 3 phase 130 watt 60 VAC generator. The search continues. I really don't want to resort to a used one as I know that they will eventually just quit working.
    #56
  17. Seikkailu_R

    Seikkailu_R Been here awhile

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    #57
  18. Highside>Lowside

    Highside>Lowside Hairier Than Thou

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    Hahahahahahahahahahaha!


    It's turned me into a sweaty, exhausted mess more than once.

    Sorry I missed this thread until now. I love my RXC, but my wife hates it. I have a interesting relationship with this tall, pale Austrian. Never show fear or weakness, and never, ever let her think she has the upper hand. I know it has been said before, but if you have to do it again, the shock does indeed drop out the bottom while sitting on the stand. Changed mine in my driveway in about a half an hour. An hour and a half, if you count the head scratching, and going back into house to clear my head. :D
    #58
  19. bmwktmbill

    bmwktmbill Traveler

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    Haha is it.
    You have to work the swingarm p and down and twist a little...and the shock drops out the bottom like there is magic at work.

    Heavier than it looks, watch your fingers.
    b
    #59
  20. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    That looks promising. Thanks. I've PM'd the OP - if that will indeed work for my bike, I'll happily pay for it. But, the more I dig into the electrical on this KTM, the more baffled I become!
    #60