I have a friend selling his 98 WR400. I was wondering what is the differance and what can be done to make is more like the YZ? One thing I read about is the throttle stop. I believe my friend installed the one from the YZ. Is there any jetting change for this? Will I notice more rotation of the throttle with the YZ stop installed. Any assitance will be appreciated. My friend has always had a hard time starting this bike. I read some threads on the techniques needed to start. I plan check it out on Sunday. Thanks, Tiny.