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03 crf450 gremlins, getting zapped and high rev's

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I am not new to four strokes and figured I would have this bike figured out quicker than its taking. I have a 06 kx450 which I have always done all my own work on and its never produced one issue but this crf has me puzzled.

First thing I need to address is start up and idle. It starts up fine but it idles way to high. With the choke on it does its normal rev but instead of calming down is stays high. Turning the choke off pretty much does nothing. I assumed this was an air leak and stripped the bike down to see the carb wasn't fully seated in the intake boot. I cleaned the carb at this time as well and re-installed. Fired it back up and same issue. It calmed down for about 5sec but any touch of the throttle the rev's kick back up and hold. I tried to adjust the idle adjustment screw on the carb with no real luck. The bike is getting stripped down tonight so I might as well go over everything.

Another issue that popped up is when I grab the front brake lever while the bike is at its high idle mark I am getting current coming through it and into my hand so now there must be a wire touching somewhere. It does not happen on the clutch lever however.

Are there any known previous problems with certain gaskets, boots, etc that could cause this thing to rev out without throttle? The cable isn't binded up or anything either but I might replace it anyhow just to be safe. Would the intake valves be a possible culprit even though the bike starts easily? Any ideas would be helpful. I would like to try and get this bike out this weekend to see if I even want to keep it or not as a dune bike.

Thanks

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I found a split wire on the ignition coil. I have been looking at schematics but do not see what exactly the wire is. There is a bolt and nut that goes through the top of the ign coil and there was a wire cut in half. I found a green wire coming out of the harness that is cut and looks like it was spliced back together which that gave out. Can anyone verify what the wire is that comes off of the coil? If its a ground this most likely is the culprit to me getting zapped.

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Your idle issue is the hanging idle. Do you know what jets are in it now? One problem with the fcr carb is that the needle jet wallers out. Even though it make look perfectly round. Your best bet would be to change all the jets back to stock and start anew. Another thing to check is the air fuel screw itself. Make sure the oring is still in place and is in good condition.

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I pulled it all apart a little ago and cleaned everything out and made sure there was no dirt or gummed up areas in the carb. All jetting is stock after comparing what was in there to the 03 carb settings and screw is turned out 1.5 turns. Was not familiar with the needle jet issues but I will have a closer look. What about the actual idle adjustment knob, is there a stock position from that I can go off of. I see no mention of it in the manual?

What is puzzling me now though is I found the manual online and downloaded it. The green wire off of the ign coil that is cut in half is in fact the ground. How is it possible for me to even get spark? I still have trace all the wiring to see if there are any other areas that are spliced or split. I have never felt voltage before through any of my other bikes and I do on this one when pulling the front brake lever.

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fix the wire and replace the kill switch.

for the high idle, inspect the hotstart. more than likely it is stuck open and/or not enough slack in the cable.

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fix the wire and replace the kill switch.

for the high idle, inspect the hotstart. more than likely it is stuck open and/or not enough slack in the cable.

x2! :lol:

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I will double check the hotstart but it seemed to be operating properly and there was slack left in the cable. Where does the kill switch play a role in all of this? The wires look fine and it shuts down upon using it so I am a little confused. Why would the ign coil still fire if the ground is cut though?

Thanks for the responses so far, heading out to the garage shortly

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It may be possible that your ignition is getting advanced somehow do to the missing wire connections?? Along with possibly a miss adjustted carb could cause this? Have you turned the idle screw all the way down??

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I have turned it down some but not all the way. I was going to do that next and I was seeing is there was a base point to where it should be. Like all the way in then 1 turn out etc.

When I first fired the bike up before taking it apart to clean the carb and everything it did the same rev and I adjusted the idle knob down. The idle dropped but as soon as the throttle was touched it jumped back up and held high again so i ruled out the idle as the actual main culprit.

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I would lower the idle screw all the way down and see if it make a diff?? Then readjust the fuel screw etc. Its probably running Lean?

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New ground is solder on, idle knob turned in and hot start cleaned, adjusted and cable slightly lubed. Have to get a connector piece for the ground tomorrow so lets see what happens.

Just to be sure though, is there any other ideas on the idle and shocking? If this doesn't work what's next to check since I have the bike basically stripped down.

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Idle nob turned in?? That would be full High idle. You want to turn the idle screw out? And fuel scre to start with at about 1.75 turn out.

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Disconnect the TPS connector and see if the high idle stops. If that is it find the readings in the manual to reset it.

Before you do anything do the idle drop method on the fuel screw. 1.5 turns may not be enough and you may be running lean. Open up the fuel screw to get the highest idle. Then reset the idle to 1800. Then adjust again to see if the fuel screw will raise it more. Repeat until it will not go any higher.

I would remove the harness and inspect it. I would also remove the stator cover and inspect the wires from the coil to the connector.

Is the shock you are getting feel like high voltage (a ZAP that runs through your body like when touching a spark plug wire) or like 100VAC from a wall outlet?

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when the kill switches short out, they will shock you through the bars. That is how it ties into your issues.

For the carb, again hot start. Also the TPS as suggested, turn the fuel screw out 2 turns and adjust the idle. again clean out the pilot jet with compressed air and the air passage in the carb. Also clean the 1 way valves in the bowl and carb body. remove the leak jet and blow out through that passage and jet. Inspect the diagphram for the AP pump also. If you need more info on the TPS, I can C&P a writeup I did years back to help with it.

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sorry for the confusion on the throttle stop knob. It looks like that was turned in a good amount even though I turned it out a few turns to back the idle down. With the subframe pulled at this time I looked in from the rear and I was still able to turn the throttle stop screw out about 3 more turns before the slide would seat itself all the way down. I adjusted it for right now to have a small gap and will go from there.

The zap I am getting isn't exactly a quick shock, it is almost like if you hold a 9v battery to your tongue, except it is coming through my fingers.

I will see where I stand today and check the kill switch if the issues are still there with the electrical issues, the carb was fully taken apart and every jet and orifice cleaned out and blown out.

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Looks like it may be good to go. There is still a small throttle hang but I believe I just need to do another half turn out on the fuel screw. I started with the throttle stop almost shut and was able to get it running and set idle that way. The previous owner must of had this thing almost all the way in prior. She is pissin a little coolant but I don't know if that because I haven't really been able to get out and run it to get air flowing or not. There is a 1.1 rad cap on there and I have seen many like to bump that number up a little. I am going to flush the rad first and put new fresh water and antifreeze in with some water wetter and see how that goes.

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