Main thread is 20 TPI. Note early manifolds do not come with carburettor studs and nuts, they are seperate parts, use the following bolts and nuts
Bolt part number BOLT-CYCLE-007 5/16 x 1 inch long bolt cycle thread x 4
Nut part number NUT-CYCLE-02/SS 5/16 cycle thread nut with a slim size hex (across flats) x 4
