Gray wire mod, work on a 00 426?

13 replies to this topic
  • wrenchard01

Posted July 03, 2004 - 02:16 PM


Hey Ya'll, does the gray wire mod. work on a 00 426?


Posted July 06, 2004 - 03:14 PM


what is the gray wire mod? what does it do?

  • wrenchard01

Posted July 06, 2004 - 07:30 PM


I'vew read, if you cut his wire, since it changes the ignition mapping, timing curve, whatever you want to call it, that you can get rid of 25% of the engine braking. I think these bikes have different timing for decel when the bikes in gear, and thats what that wire does, where it is on my bike I dont know, Barton sent me a link on another jetting post of mine about bog, if you want to read it, but it says nothing about my bike, only 250's, and I dont know if that applies to my bike or not? Good luck, Rick.


Posted July 06, 2004 - 09:13 PM


i looked at the wiring diagram for my bike and it doesnt show any gray wire. so does this mean that it doesnt apply to '00 426's?

  • John_Lorenz

Posted July 07, 2004 - 03:46 AM


The Blue Wire mod is for the YZ, the Grey Wire is for the WR, DO a Search in the WR for Grey Wire Mod

Here is a link for the Blue Wire
Look under Tech Articles then
Make your YZF start better

I have the 2000, I did the Mod made no differance, some though sware it stopped plug fouling and made the bike start easier. As I said, My bike it made no differance.

  • ovrrdrive

Posted July 07, 2004 - 06:42 AM


Word on the blue wire mod is that it makes the bike think it's in gear all the time so it doesn't reduce the coil voltage, or something like that.

My only problem with even bothering to try this, is that my bike only seems to want to start in neutral. If by disconnecting the blue wire the bike thought it was in gear all the time, wouldn't that make my bike harder to start?

The thing fires up on the 1st kick when cold, and the 2nd or third when hot. I'm afraid to screw with it as I doubt it could get any better.


  • wrenchard01

Posted July 07, 2004 - 10:34 AM


Thanks John, may see what it does, later, Rick.

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Posted July 07, 2004 - 11:19 AM


i already did the blue wire mod and it made no difference to my bike whatsoever. also did it to my friends 250f and it didnt help starting either. im in the process of doin the bk mod so i hope that makes a good difference.

  • John_Lorenz

Posted July 07, 2004 - 11:23 AM


Here is a write up I did on the GBmod

web page

  • markvan

Posted July 07, 2004 - 04:00 PM


My only problem with even bothering to try this, is that my bike only seems to want to start in neutral. If by disconnecting the blue wire the bike thought it was in gear all the time, wouldn't that make my bike harder to start?

Actually it would make your bike easier to start. Because it thinks it is in gear it is sending full voltage to the plug at all times, not just when it is in gear. When it is in neutral it cuts the voltage down, by doing the mod it will keep the voltage higher, giving you better spark and making the bike easier to start, and fouling less plugs. But if your bike is easy to start now why bother. My bike starts fine without the mod, 1st kick everytime, and no fouling.

  • TampaBoy813

Posted July 08, 2004 - 01:13 AM


wow I will have to look in tot his after work.... :thumbsup:

  • Fastest1

Posted July 09, 2004 - 03:37 AM


Well it did and does work on mine. It is easy to remove from the harness and you can always reconnect it if you didnt cut it. To whoever claimed that their bike starts 1st kick cold but 2-3 kicks warm, you are running rich. Try a smaller pilot. Nobody would ever think their bike would run better, but if you dont try things you will never know. When you were a kid you probably thought your hand felt better than anything else :devil:, then you discovered girls! :awww: :thumbsup:
BTW Tim Ferry's 2000 YZF426 didnt run the neutral switch (I wonder why?) He also ran the BK mod named after his mechanic Brian Kinney. You make the decision, But if you disconnect it at the harness you can always put it back.

  • ovrrdrive

Posted July 09, 2004 - 03:42 AM


That's amazing you can diagnose the entire jetting condition of my bike that easily... You missed your calling. :devil:

Think it might just have something to do with the fact that my bike only has about 2 hours on it instead?

I probably will change the pilot jet though, but I want to go bigger. Right now I'm staying out 2-2 1/2 turns on the screw. I've read that it's better to go up and cut the turns down.

Honestly though, I really hate to screw with it. As I said it runs great and starts pretty easily.


Oh and btw, I always kinda figured that real girls would feel better, but I'll be damned if my hormones didn't kick in well ahead of my skills to get girls did. And you're right, it was worth the wait. Lucky for me I've been married for the last 9 years to a woman that actually likes it more than I do. My hands are for holding onto grips now, and a few other things from time to time. :awww: :lol:

  • Fastest1

Posted July 10, 2004 - 01:54 AM


Now that I see where your fuel screw is set, I would just recommend turning in the fuel screw a bit. It should help it start quickly both ways, hot or cold. Regarding the hands, they arent near as much fun after the callouses from riding. Who said girls mature faster anyway? Boys were always ready before they were!

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