Front lower Cylinder head bolt loose

[hooverdm]

I've amended the post. Now that I've found the nut missing on the head bold below the exhaust, the bold itself is loose and resting on the ledge. Does the bold screw back up into the head, or is there a nut on top somewhere?

I thank folks that posted info on replacing the cylinder head gasket, with the advice to check the stud bold that is positioned in the front as it is often missing. Mine was indeed missing. Can anyone tell me what size this nut is and is it a special type? appreciate your help
Dave H
San Antonio, TX

[fuentes956]

If is from the front of the engine is a 10mm nut (lower cylinder head nut), mine was missing to when i bought the bike. I bought the nut from autozone.
http://s12.postimage.org/ikpsfvh1l/GZ250_10mm_nut.jpg (http://postimage.org/image/ikpsfvh1l/)

[hooverdm]

That's the one I'm refering to. Thanks.
Dave H
San Antonio