2004 WR450F Gray Wire Cut

8 replies to this topic
  • trunkmonkey55

Posted April 14, 2004 - 01:26 PM


Whats up with the Gray wire cut. What gray wire?

  • mtrablue

Posted April 14, 2004 - 04:59 PM


use the search feature and you'll find plenty.

  • YamahaSteve

Posted April 14, 2004 - 05:03 PM


The gray wire tells the electronic ignition computer whether it is a YZ computer of a WR computer. If you disconnect the wire then the computer thinks it is installed on a YZ and therefore gives your WR the YZ ignition mapping.

The actual job is simple and is well documented here and elsewhere. Good luck!

  • RobRantzow

Posted April 14, 2004 - 05:13 PM


Really what the grey wire does what I've learned is a WR'S timing is retarded at mid to upper RPM. Why? no good reason I want to know about. But I'll tell you that when you (Cut the grey wire) the bike runs alot stronger in the mid to topend. Without hurting the bottom end at all. Ther only thing I would suggest is not cutting the wire but pulling it out from the 6 pin connector on the right side of the tank so that if you want it back you can put it back together.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • trunkmonkey55

Posted April 20, 2004 - 07:31 AM


is it still good to pull the gray wire on the 2004 WR450 :)

  • jerryls

Posted April 20, 2004 - 08:00 AM


Seemed to make a difference on my '04. Not a huge difference, but noticeable.

  • YamahaWR450FMike

Posted April 20, 2004 - 09:27 AM


what if you cut the gray wire on the 04 WR450F and then don't have the cam timing changed. What happens then?

  • jerryls

Posted April 20, 2004 - 10:24 AM


:) I didn't change the cam timing, just unplugged the wire. Runs a little bit better.

  • mtrablue

Posted April 20, 2004 - 12:40 PM


yamaha made our bikes to be able to pass a 85db test. the exhaust and air box are plugged up to help meet these standards. the ignition timing is altered to go with all that. yamaha did us a favor by having the second ignition curve programed in. honda has done the same thing with the new crfx250. they just say it's for "closed course use".


Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.