Abstract: Abrasive belt machine tool for machining cylindrical bearing surface on shafts, in particular journals on camshafts or journals and/or crank pins on crankshafts, comprising for machining each bearing surface two opposed jaws 5 mounted on two arms 1 and each having first and second concave application surfaces 6a, 6b having different diameter in at least two different positions. The abrasive belt 9 passes in front of the concave surfaces 6a and 6b of the two jaws 5. The support 2 of the arms is mobile between at least two positions such that in one of said positions the first concave surface 6a can apply the abrasive belt 9 to a bearing surface 8a having a corresponding diameter on a first shaft and in the other of said positions the concave surfaces 6b can apply the abrasive belt 9 to a bearing surface having a corresponding diameter on a second shaft.