I might have those off the 61x cases?Case bolts. :bigok:
You MUST use M10 bolts with 12mm heads. Otherwise, a socket will not fit on the bolt head.
Theres a guy on Ebay selling stainless M10x1.25 Allen heads. They're $6 a piece, they are not that strong, and they like to gall with the aluminum manifold.
I suggest you use OEM case bolts (short one).
Let me know. Joem yamaha exhaust bracket bolts work too i might have some