There SHOULD be oil in the stator, that is how these engines are designed.
Before you tear it down make certain the decompression lever, cable, and actuation lever down on the motor are all operational and working/adjusted correctly.
On my 1999 if the decompression lever on the handlebar is rotated up, even a little bit, it can tighten up the cable to where it actuates the decompression lever and will kill the bike, or prevent it from starting. This is real noticeable as it does not stop the motor when rolling it over to top dead center.
Both the YZ and WR's are pretty bullet proof and very reliable in most instances, unless severely abused or not maintained. Why do you say you know it needs a rebuild? Did it smoke, miss, not have power?
You say it was running fine and just quit. Did it make any BAD noises, like a crunching or other awful noise, or just stop running and you coasted to a stop?
Thanks for replying, good info.
I know just what you mean about the decompression lever, I adjusted it all to my preference when I first got the bike. I am 99.9% sure the cable is in good order and not binding, and that it is actuating the valve correctly. It goes back in place so smooth, I can do it fast like just drop it like the clutch and hear a tiny click down there when it hits closed position..
The most notable concern is that there is no dead stop at the top of the kick anymore, decompression lever pulled or not, same amount of compression over and over. It sounds a little more throaty with the lever pulled. Also, I can really smell it when I turn the petcock to on and start kicking it over, that gasoline smell with a hint of dirty carb, so I'm gonna guess that the jets aren't fully stopped up. In the tank is brand new highest grade pump gas.
When I did ride it, it wasn't quite perfect, seemed to bog down sometimes, at low rpms, kind of just a dirty carb feel, nothing really of note just needed a tune up from sitting around. So no BAD noises or smoke, and the power was SO there, when I opened it up. Never heard crunching or explosions or metal shavings inside my cylinder lol..
My last ride: Going down state maintained paved double yellow line road, mildly, 5th gear but only about half of what it can go, just cruising, then a simple solid KILL SWITCH, as if I were pushing the stop button myself...
Yes, I then coasted to a stop at what happened to be a buddy's house...
Could it be blown out rings? Timing chain jumped? I think my hardware is intact, what say you?
PS. I have not put my mind to the deep mechanics of motorcycles/atv's, but I can ride with the best!
ALSO: I called the Yamaha dealership service dept. and told them the mis-diagnosed my bike, they are "looking into their records" and gonna call me back. Will update later.
Edited by gregnextdoor, March 18, 2015 - 10:48 AM.