Looks like there is a threaded headset under the clamp, right? The Ti fork is not threaded, unfortunately. Using a threaded headset solves the problem but creates a new one, one of non-compatibility.
Bike Friday has a number of different forks the one shown may have a slot in the treaded Steerer so the collar compresses it around the Easy Pack Stem mast.
pictured in 206
My Pocket Llama came with a Wedge-Quill fixed folding Stem-Mast, so It did not get the slot cut in the steerer tube, but still uses the CK grip nut headset.
Since I got my bike , the gang in Eugene has a Threadless fork & headset option . I hve not seen one in the flesh, But, problem solvers micro adjustable spacer
Problem Solvers , beneath their reinforcing clamp on piece
once its clamped around the steerer tube, like a stem, can be used to pre load the Headset adjustment that last little Bit.
so there are mechanical workarounds..
then the rest of the Mast can be clamped around an Alloy wedge quill Tube that goes Inside the steerer .. the rest of the Mast tube Can Be Titanium if you wish.