Originally Posted by
Dan Burkhart
Steerer threads can be extended, and excess length cut off. It used to be standard stuff at bike shops, so just find an old shop, and they can probably help you out.
The loose crown race is probably a JIS/ISO issue. Your old fork was undoubtedly a JIS with a 27mm race seat, and the new one is likely ISO with 26.4mm seat.
I have corrected this with a knurling tool to emboss the race seat to make the effective diameter larger. The same thing can be accomplished with a centre punch. When doing this, it's also a good idea to use some kind of assembly compound such as Loctite 680 to keep the race firmly in place.
Thanks for the reply Dan!
If I bought a 26.4mm ISO headset to fit my new steerer tube, would I have to replace the JIS pressed frame races?
Also... I assume having a bike shop cut new threads in my steerer tube is going to cost more than 20 bucks (the cost of a correct-height tube)?
Edit: I noticed that the ISO standard cup outer diameter is 30.2, while the JIS is 30.0. So ISO cups won't fit my frame? Sheldon Brown's site claims that both JIS and ISO have the same threads per inch on the headtube- so why doesn't my threaded race thread on?