I have a NOS Supercross to build. I bought a 45/36 headset as that’s what I thought it needed, but it just falls through.
The headtube measures (with an old tape) about 48mm OD and 42mm ID.
There is no angular face inside the headtube, just a 90o face about 10mm in, both top and bottom.
It now looks like I need an FSA Orbit Z type, one with a shell that presses in that accepts standard bearings, but all the measurement are out?
Bare in mind the frame is 2006/08 so shouldn’t have anything fancy. All the old bikes on the net have FSA’s so hopefully that would rule out anything like Microtech?
If you do have a Ridley of that era can you have a peep?

Thanks to fellow STW’er the Bear of Bear Bikes I have a bike to ride this weekend. Some minimal machining and I’m good to go.
The correct headset is virtually non existant so he machined down one slightly larger.
Cheers