Blue smoke?

[400exRacerX]

Hey,

I had noticed from riding this past weekend when I let my friend ride my 400 that every once and a while when you let off the throttle it will shoot out a puff of light blue smoke. It doesn't shoot out the smoke everytime I let off the throttle just every once and awhile. Maybe I'd say every 1 out of 5 times. My question is, Is this a early sign of bad valve seals? Or are my rings shot? I am going to take a compression test to see if its my rings, does anyone know what the compression should be at? And what do you think is wrong?

Any help would be greatly appreciated.

Thanks, Norm

[BigRider69]

I have a Yamahaw Pro-Hauler
and it does the same thing. But after
tinkering around I found out that the
rings in it were shot to nothing. Hope this
helps.