Rabaconda Dirt Bike 12-18mm Adapter Spindle This adapter spindle for the Rabaconda Dirt Bike Tire Changer is made specifically for bikes with a smaller hub bearing. Spindle diameter is 12mm and comes with an 18mm adapter (original Rabaconda spindle diameter is 20mm with a 24mm adapter). Features: 12-18mm adapter spindle Designed for bikes with smaller hub bearings Electro galvanized steel axle construction Anodized aluminum sleeve Note: For use with Rabaconda Dirt Bike Tire Changer only.