Joined: Jun 2011
Posts: 6,674
Likes: 26
From: STS
Bikes: Leader 725, Centurion Turbo, Scwhinn Peloton, Schwinn Premis, GT Tequesta, Bridgestone CB-2,72' Centurion Lemans, 72 Raleigh Competition
If it's an old 10 speed unless someone before you did a crazy upgrade on the wheels, it is a thread on freewheel.