Bicycle Bearings - Press and Extract

thingiverse

I needed to service my Giant / Yamaha Syncdrive Pro Ebike motor; it has four bearing sizes: 6807 and 6805 for the Bottom bracket bearings 6802 and 6800 for gear idlers I needed a simple extracter (and cup for other side) and press tool to remove and fit them. I created these in ABS; longer term I'll machine them out of Aluminium but they work fine for the occasional use. The 6800 uses a 6 mm bolt, two washers and a nut to complete. The other three use an 8 mm bolt, two washers and a nut. To extract a bearing put the cup on the side the bearing is to be pushed to to receive the bearing, pass the bolt through the centre, Fit the 6800 extract into the bearing with bolt going through. Fit washer and nut. Tightening the bolt draws the bearing into the cup. To fit a bearing, slap some grease around the outside of the bearing, pass the bolt through the press, place the cup on the other side, fit washer and nut. Tightening bolt presses the bearing in.