Originally Posted by
hokiefyd
I may have given you some bad info. It looks like the stem CLAMP diameter (to clamp the handlebar) is commonly 22.2mm on a BMX bike (vs. 25.4mm for mountain bikes). I couldn't find anything on the steerer tube diameter. The suggestion for the other forum is a great one. Good luck!
Yes and no. BMX bikes have evolved over the years. "Old" BMX bikes used the Schwinn standard headset: 32.6mm OD on the headset cups, 1" OD, 0.833" ID steerer. Newer bikes use 1 1/8" threadless while the newest are using "integrated" headsets.
Kids these days...