my old cheap calipers are rusty, all three VO stems say 26.0, two Nitto bars say 26.0. the bar clamp pieces on both stems in use on two bikes are within one or two papers width of bottoming out. This third new one is on a one year old Nitto bar and it's bottoming out. Without calipers I'm guessing that the bar clamp piece is simply a smidge too large. Filing the face of the bar clamp piece might be an idea.