Hey there, I have a couple of questions about my 2002 YZ 426. #1- What is this thing I keep reading about called "The Gray Wire Mod"...does it apply to my bike and what does it do? #2- I just got back from four days of riding in the Nevada desert. We were at about 4000 ft. and would take rides up to about 7200 ft. each day. My bike ran like a top...it always started on the first kick..never had one problem at all, I would ride it all day just ripping it on high speed trails and tons of climbing. I live at just about sea level.....and it never runs this good at home...ie. some times hard to start, bogs down on hills more, just doesnt feel as good as it did in Nevada. What do you guys think? jetting issue, fuel mixture...not to sure and all. Anyt help would be cool.