Size: 1 inch (toothed)
The inner diameter is 22.2mm, the outer diameter is 25.4mm, the inner diameter of the frame head pipe is 30mm, and the diameter of the front fork base is 27mm 
Size: 1 inch (toothed)
The inner diameter is 22.2mm, the outer diameter is 25.4mm, the inner diameter of the frame head pipe is 30mm, and the diameter of the front fork base is 27mm