I've seen this question posted a lot in other machining forums but I'm still confused. I'm machining a motorcycle hub spacer from aluminum to put in a wheel bearing. It needs to be press fit and I just want to know what the ID of the bore should be. Most answers I've seen are something like "check with the manufacturer of the bearing", so I'm on their website and think I found some info that will help but I don't really know what I'm looking at. I was hoping for a PDF saying something like "the bore ID for this bearing should be .0005" under size", or something like that. It's a KML 60/22-2RD bearing which is 44mm OD and 22mm ID. Can someone help me out? Here are some links that may help. http://www.kmlbearingusa.com/produc.../metric-single-row-deep-groove-ball-bearings/ http://kmlbearingusa.wpengine.com/wp-content/uploads/2016/02/P174-DG-Internal-Clearance.pdf Thanks!