wr 400 grey wire

Ok I know this issue has been run into the ground but, I still can't run down exactly what I need to know. I know what the grey wire does and what removing it does. What I dont know is exactly which wire it is. I have a 99 WR 400. I have searched this topic many times and still can't find it. Some say it is a two prong connector some say six. I do know that the grey wire that i dont want is a two prong going to the kill switch. From the wiring diagram in the shop manual, it looks to be a six. Can someone help?

Take the tank of , rite side of bike ( if you were siting on it ) the connector should be along side the frame tube that the tank set's on ,near the black box. There should a picture of the connector some were . I did it a long time ago so i really don't remember exactly how many wires were in the plug but i think it was only two or three . It really makes the thing run like a different bike , did wonder's for my 98 400.

Ok I know this issue has been run into the ground but, I still can't run down exactly what I need to know. I know what the grey wire does and what removing it does. What I dont know is exactly which wire it is. I have a 99 WR 400. I have searched this topic many times and still can't find it. Some say it is a two prong connector some say six. I do know that the grey wire that i dont want is a two prong going to the kill switch. From the wiring diagram in the shop manual, it looks to be a six. Can someone help?

i cut it and noticed nothing,

Please tell me what it is supposed to do?

did you yz time the bike yet?

Take the tank of , rite side of bike ( if you were siting on it ) the connector should be along side the frame tube that the tank set's on ,near the black box. There should a picture of the connector some were . I did it a long time ago so i really don't remember exactly how many wires were in the plug but i think it was only two or three . It really makes the thing run like a different bike , did wonder's for my 98 400.

wow i have a 98 wr 400 also, did nothing for mine!

Thats just the thing, I bought this bike used about two weeks ago and I am trying to run down what has been done. I haven't torn the bike down that far yet to see if it is YZ timed. I do know that the grey wire hasn't been cut yet. From my understanding, the grey wire, when grounded, makes the CDI use a WR mapping for the ignition. When the grey wire is cut and not grounded, the CDI box automatically goes to YZ maping. Does this sound right?

Thats just the thing, I bought this bike used about two weeks ago and I am trying to run down what has been done. I haven't torn the bike down that far yet to see if it is YZ timed. I do know that the grey wire hasn't been cut yet. From my understanding, the grey wire, when grounded, makes the CDI use a WR mapping for the ignition. When the grey wire is cut and not grounded, the CDI box automatically goes to YZ maping. Does this sound right?

I dont think it does anything. IT did nothing on my bike.

shit, I tried like hell to pull the connector apart to cut the fu*cking wire and couldn't get it apart. Then I kept reading how so many of you saw no results from cutting the wire, and decided not to mess with it. I think I'll retard my cam timing and play with the jetting...and really, my 426 can be a handful as it is.

as far as i know my 400 is wr timed , you need to open the air box , ( the only thing the lid is good for is to see how far you can through it ) and cut down the throttle stop . I have been riding since my early teens and i aim 47 now and the power the wr puts out puts a smile :cry: on my face every time i ride it . :cry:

I agree with Rowlee do the air box, and throttle stop and ride it like you stole it. Will run for ever with the right TLC

OK guys, my thoughts are that if you are going to take the time to cut the grey wire to use YZ ignition mapping, I would go ahead and retime the cams. You will need to advance the exhaust cam timing by 1 tooth. This has been done by many and is not that involved. It does produce very measureable results. I was a skeptic at first, but was totally sold the minute I fired it up after the job. You can feel and hear the difference. The motor definitely likes the switch. If done right, probably an hour job max. You can search here to find specific instructions. I think this is the only way to full advantage of the yz mapping.

So if I have already installed the auto-decomp exhaust cam from an 03 and I had to rotate the cam forward one tooth from where it would normally be timed, does that mean all I have to do it cut the grey wire and it will be YZ timed?

My very first Thumpertalk post will be on the grey wire.

YES the WR400 has a grey wire, and it DOES make a difference! It's the two prong connector that's by the top frame tube right behind the right side radiator under the tank. There are two other connectors next to it with more than two wires and no grey wires. They also go to the CDI box.

DON'T CUT THE WIRE! If you take a skinny nail or some other pointy object and slightly pry the plastic tab in the plug that holds the metal contact in, the wire and contact will slide out of the plug without cutting it so you can plug it back in without splicing the wire if you ever decide to hook it back up for some unknown reason. Just slide the wire out of the plug and put some electrical tape on it.

I just bought this WR and joined this site a few days ago and I can't believe haw many incorrect things people are posting!!! If you haven't done it or don't understand it, don't give advice on it.

P.S. Thanks to all of you guys that give correct advice on here! You've saved me a lot of time despite the others trying to confuse the issues. :)

About the grey wire, it is a two prong and the wire next to it in the plug in is black with white stripe. I lost a lot of low end when i changed to yz timing, i will probably change it back.

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