[gersting]

More details please, I am not familiar with the type of headset. I'll assume its Aheadset. Integrated? Carbon steerer on the fork? Assuming that its an alloy steerer, remove and grease the star nut bolt. While its out, take the cap off the headset and check that the stack height of the stem/spacers exceeds the height of the steerer tube by 2-4mm or so. Otherwise, the cap will bottom out when you attempt to tighten the headset. In some instances it will catch and feel too tight, in others, it will be too loose.

post some more info though

 

[gersting]

FSA integrated headset. The fork has a carbon steerer tube, so there is no star nut. The cap is definately not bottoming out, I actually removed a spacer because I had too much of a gap.

As others said, check the crown race. Also, removed the whole expander plug from the steerer tube, check and grease. if it is worn (or just has rubber deteriorating), improperly installed, or needs grease, it may not be expanding properly.