Did I sleep through something?

Grey wire? I tried reading through that post but got lost pretty quickly (forgive my small brain. I just ride them folks, I don't understand their inner workings).

Here is what I gather, cut this wire, bike goes faster. This is a good thing. Now if someone can answere some simple questions...

Does my '99 have one?

If so, does this mod work on the '99 (YZ timed)?

Where the hell is it on my '99?

Can someone link the original post explaining this concept?

Thanks, Doug


I didn't get it either. Does my 2001 WR426 have one of these? And what is it suppose to do?


Maybe someone can correct my understanding of this. It seems to me, that the modification changes the mapping or ignition curve :D

The reports have varied from great to I can barely feel a difference. Some are also saying the "mod" is more effective on 01 bikes. It also does not seem to matter whether the bike is YZ or Dub-R timed :)

The post started on the 250 side of TTalk.

Yes you have one on your 99

It's located under the tank. It's a two wire plug with one gray and one black wire.


How's the young'n Doug?


99 WR400f, YZ timed, MX-Tech suspension, Scotts steering damper, White Bros E-Series (12 discs), tapered header and a/f. Kouba T-handle for the fuel screw. Works Connection billet throttle tube and frame guards. Cycra Pro-Bend, triple clamp mount handguards. Thumper Racing rad guards, Renthal Jimmy Button highs, YZ Tank and IMS seat, YZ number plate, odo removed, EKP, 48PJ, 175MJ at 500-1000' Thanks James Dean!

Heres my 2 cents

I cut the wire and I did not notice any power increase BUT my 40 to 55mph stuttering/surging was gone

I always thought it was a jetting problem but all I had to do was cut a little grey wire.

cut away!!!

Thanks Bill. And the young'n is doing just great. Thanks for asking. Getting cuter everyday (gets that from her mother). Starting to move all over the place. The days of putting her in the bouncy seat and working on the bikes will soon be over.

I figure I'll give this cutting the wire a try. What they hey, don't cost nothin', right? Seems easy enough.

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