Yesterday I had a headset and fork fitted by my LBS. Lacking the specific tools or knowledge, I thought it better to leave this job to a professional; as a consequence of my inexperience, however, I have no idea whether they've actually done a good job.
As far as I can tell, the crown race fits snug against the base of the steerer tube. When the fork is inserted, however, there is a gap of about two millimetres between the base of the steerer and the bottom headset cup, leaving the crown race exposed. My expectation was that the bottom cup would instead sit flush with the fork.
Scouring bike forums for answers suggests this situation isn't all that uncommon, with some offering makeshift solutions, like a strip of inner tube to keep out grime. Still, if someone wouldn't mind taking a look at my headset specifically, it might ease my mind somewhat. I've included a couple of close-ups below.
I've checked the orientation of the bearings, and they're definitely the right way up. The slight chamfer on the inside edge of the lower bearing fits nice and tight against the crown race.
The headset is a Tange Seiki RDC-82. I don't appear to be missing any pieces.
Thank you for your help.
Update: Ok, so I gave the company I originally purchased the headset from (the same place I bought my frameset at the same time — not the LBS that installed it) a call; they instantly knew what I was talking about, and assured me it was normal for this particular model. In hindsight, ringing them should really have been the first thing I did.
Still seems like a poor design in my opinion. Not only does it look somewhat unsightly, but the gap risks exposing the lower bearing to grime and dirt. A simple seal could have solved both these issues. Perhaps when I eventually come to replace the headset, I'll invest in something pricer/better quality.
