Gray wire switch

Has anyone rigged a switch for the gray wire? I'm going to make one and wonder if I need to turn the bike off to toggle it on or off. I'm concerned about blowing the CDI unit.

Why am I doing it?

Gray wire on: Controlable low end power for tight trails.

Gray wire off: To get the holeshot. :)

P.S. Grey is the British spelling of Gray:usa:.



I actually didn't notice any difference after unplugging the grey wire.

The biggest returns I got were from the throttle stop, baffle, and the air box lid mods in just that order.

Do 'em all and you'd swear it wasn't the same bike.

Yes you would have to turn the bike off to switch it. Personaly I don't think there is enough of a noticable difference to even bother with it.

I toggled mine. As said before the ignition mapping will change only on startup so it does have to be turned off. I can tell a difference between the two maps and had the same intention as you but honestly have never changed back to the WR mapping after trying the YZ mapping (grey wire cut). IMO, the difference is noticable and desirable but not mindblowing by any means. Even though I don't toggle it I leave the switch in there for two reasons: (#1) Just-in-case, and (#2) I'm too lazy. If I were you I'd just cut the wire and be done with it.


Thanks for the info. The gray wire was the last mod that I did and it turned the bike into a MX bike. I plugged it back in and find it better to feather the throttle at low RPM. Now I just need a sano switch.


Any (Grey wire like) way to change the mapping on my YZ to WR? :)

I have my gray wire switched. I can't tell a bit of difference either way. I couldn't on my 426 either,


It's strange that some of you guys can't tell the differance between the gray wire on or off. I owned the 2001 WR426 and the low end sucked. You are excused. The ignition mapping on the 2002, which I also owned, was much better for low-end, so you have minimal excuse. (2001 owners, buy a 2002 CDI unit!)The 2003 is a monster, with gobs of low-end and the gray wire off eliminates any nuance of low-end power control. The stroke from 426 to 450 seems to be mostly low-end improvement, so the gray wire mod is most noticable.

I suppose it also come down to riding style. If you're running the bike only on a closed track, you will not notice a difference. If you're negotiating a tight 180 degree uphill switchback, it becomes a big deal.

Gray wire off turns this beast into a mx bike that will snap your neck. Not good for tight, technical trails.


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