Oil leaking out of hole in cooling fins in Yamaha (FZR600) Engine???

I just bought a FZR600 and discovered oil coming from the hole in the cooling fins on the ';passenger'; side of the head. I assume it's been dropped before but I don't know that for sure. I'm wondering if anyone knows what this hole is. I've been told by one mechanic that the oil may be leaking in from the valve cover gasket or the seals around the spark plugs. Another mechanic told me that it's just a factory drilled hole that had a plug in it and the plug probably just fell out. They said if I hammered a BB in it, it would plug the hole and I would be fine. I'm kind of nervous about hammering a BB into my engine because it would be very bad if it went into one of the cylinders. Has anyone else out there seen this type of leak and know how to fix it?Oil leaking out of hole in cooling fins in Yamaha (FZR600) Engine???
It's a drain hole.


If water gets into the spark plug wells, it goes down


the drain LOL


It never has been, or should be, plugged.


You mechanic friend gave you a good diagnosis.


I'd replace the valve cover gasket.


I don't know what year your bike is, so I don't know if it has spark plug o-rings. Some bikes have the o-rings incorporated into the valve cover gasket.


What ever your bike has, change everything that could leak oil from the valve cover.Oil leaking out of hole in cooling fins in Yamaha (FZR600) Engine???
as far as i know its for cooling you might have a bad headcasket check your coolant for oil