The gray wire on the WR is what controls the rev limiter. If you cut it, it makes it run at the same level as the YZ. I have never had a YZF so i cant tell you for sure if it the YZF has the same gray wire. I'd say go to the YZF forum and ask a couple of the guys there. Dude...you're a regular rocket scientist! One question...were you wearing a helmet the last time you crashed?