Either a plastic ring or an metal split washer. This takes up slack on the headset as it's tightened.
Have you fitted the star-nut into the top of the fork steerer tube ? The top cap bolt then screws into that and tightens everything upThanks guys, will correct.
It seems the fork tube is extra long, so I'm going to need to cut about 4 inches off...
Also, no spacers have come in the set...
I can't quite understand how the headset will get tightened. The screw in the crown just goes into a circular thing.