M6 hole under engine?
 

I noticed when changing my gear oil an M6 threaded hole on the underside of the engine, Anyone know what it is? theres nothing in it just a threaded hole. Is this a breather or should it be plugged?

If I'm not mistaken all theGasGas engines have another drain hole that is located towards the front of the motor under the crank area. That is used to drain any thing that might happen to get into main bearing area. That should have a bolt with a copper washer. Other than that an oil drain plug for the tranny. Anything else could just be a tapped hole with threads for mounting the cases to during assy process?

on the pre-2005 bike it is a breather hole to the ign. and also a fixture hole for ass'y. Some guy's plug it with a screw.