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I've just fitted an FSA Orbit MX headset; it came without fitting instructions and the [url= http://www.fullspeedahead.com/wp-content/uploads/2014/07/Headset_Installation_Instructions-Jan-20112.pdf ]instructions[/url] on the FSA website are basic to say the least.
I've fitted all the component parts as per the instructions but that seems to be a gap between the top cap and upper come big enough for me to bet a thumbnail under. Obviously the top cap shouldn't rub against the cup but I just wanted to check that I'd got everything fitted properly for peace of mind.
Everything runs perfectly smoothly with no play and feels spot on.
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I've fitted the seals flat side to the bearings as in [url= http://www.fullspeedahead.com/wp-content/uploads/2014/07/Orbit-MX-Technical-Data-Sheet.pdf ]FSA's PDF[/url] (the image of the unfitted Orbit MX in this file shows a similar gap between the top cap and cup.
Some years ago I fitted on Orbit MX to my partner's bike, which also has a gap, although this looks slightly smaller (oddly her headset cups are painted on to of the cups whilst mine are bare aluminium.
There are plenty of picture of unfitted units on the web which all show similar gaps, but this doesn't mean that they'd look the same pre-loaded.
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As mentioned, everything feels spot on it just looks a bit odd to me (used to Cane Creek headsets); the only scope for anything actually being fitted incorrectly would be for the seals to be upside down.
I've found a thread on another forum suggesting that older Orbit MXs had a .7mm gap and a .3mm gap post 2010.
Any thoughts?
I suppose that external headsets are a bit retro these days!
The gap I have is no more significant than the one shown in the picture above, but it is a shade more that the one fitted to my wife's bike. However, despite both being FSA Orbit MX headsets they are slightly different; my unit is as in the picture above whilst my wife's doesn't have the ACB text and has the tops of the cups painted over whilst mine is bare - possibly different version of the same model or OEM/Retail.
Mine, which is probably a post-10, looks to have a narrower gap than yours.
Thanks for the info. I'm wondering whether it's just variation between different flavours of the Orbit MX or a problem. As I've said there's no play, smooth steering and everything 'feels' right, the gap just looks a little wider than the Orbit MX on my wife's bike (which I also fitted).
Even so, the gap on mine is less that 1mm.
Colour aside it looks exactly like the image on the FSA Orbit MX webpage; the gap's about right too but I'm not sure whether this would close up significantly when preloaded.
The upper surface of the cups on my headset are bare metal as in the photo below; on my wife's bike they're painted over.
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