I used a hammer and a screwdriver to get the cassette off, just unscrew all of the shields and stuff and the bearings will fall out. Then put the freewheel in a vise and turned the wheel to get it off. I picked up a single speed freewheel off of ebay for $10.95. It looks very clean, I like it! I like the idea of a SS for some simple trail riding, good build!