[62752]

New Monster rider, dumb question re. oil check window. Clearly on right, bike upright, oil looks great. What on earth is the spy window on left side of bike for?

 

[mscuddy]

On the old PANTAHS, one of the windows was used with a timing light for ignition timing.

Maybe the same deal with your Monster?

 

[The_AirHawk]

That's not a Window - there's a hole in the crankcase where an errant rod punched its way through. That was what that "knocking" noise was.........:-o

 

[58962]

The glass on the left side is to see the TDC and timing marks on the edge of the flywheel. You'll see a little oil on the flywheel or the glass from time to time.