I'm setting up a motorcycle front end from used parts, and some of the mounting bolts were not included. The same bolt is used both for mounting the calipers to the forks, and mounting the brake discs to the wheel hub. I've found the size and part number (M8 x 30mm) that is used on the OEM parts, but it does not indicate what material or grade of bolt to use.
Stainless seems like a good option because of corrosion protection and I was able to find these in an A2 alloy, but I'm concerned because of the considerable shear force that may be put on the disc mounts. FYI The torque spec is ~20 ft lbs.
Will these A2 bolts be sufficient? Or Should I go with something stronger, say a carbon steel 12.9 grade bolt?