any one know what size thread the two bolts are that go into the threaded holes in the block of a 5vy r1 engine

If they are the same as the 5pw they are an m10 fine thread (1.25 pitch)

Dunno about 5VY but they are M10 on the 5PW, torqued to 45Nm. As this is a pretty low torque for an M10, I used 8.8 bolts, loctite and spring washers to be on the safe side.

Nick