location dowel pin, cylinder head engine/clutch casing barrel 16/15/14/12/10/8/6
16mm dowel has a 14.2mm bore - clearance for M14 bolt. 15mm dowel has a 13.3mm bore. 14mm dowel has a 12.20mm bore - clearance hole for M12 bolt. 12mm dowel has a 10.2mm bore - clearance hole for M10 bolt.