What is the International Standard Mount distance for 148mm rear axle?
Hello, I'm new here. I'm projecting my first bike frame, so I'd like to know if the IS mount is located at the same plane as the wheel socket or is there a distance between them and what is the distance. I've already found the 51mm distance between (6.2mm diameter) holes and 39.9 and 78.1 between them and the axle. But some images I found show them at the same plane, others, at a 3.5mm distance. Can someone please clarify?
Also, is the wheel socket diameter exactly 20mm?