Review on Enhance Steering Stability: Universal 31mm Aluminum Steering Damper Fork Mounting Bracket for Motorcycle Bike Modification by Chef Deane

The frame I put it on is 2" in diameter, and 50mm isn't even close. It measured from 48.88mm to 49.3mm depending on where you measured around the hole. I'm lucky enough to have the equipment to fix this, but if you don't mind a drill and sandpaper on a 1/2 inch wooden dowel they will do it for you. I gave it three stars because I was able to fix the problem and it looks good.