Re:600 grizzly oil level?!
When the engine is running, you will more than likely not see any oil in the sight glass. This is normal.
The best time to check the level of the engine oil is about 5 mintues after you shut if off. Thats even written right in the owners manual.
The level should be apprximately 1/2 -3/4 up the sight glass. Any more than that and the engine will blow the over fill in to the airbox. Any less, well that is self explanatory.
Some years had sight "lines" on the sight glass. My 1998 does not, but the manual calls for 1/2-3/4 up.