stack height/steer tube difference
 

I have headset stack height 1.5-2.0mm longer than the available steer tube would be okay? I only have about 31.5mm of steer tube threading and would rather use the Tange Levin over the Passage because I think it is better quality and would have to cut 1-2mm off for the latter. I measured 6.4mm of available threading on the headset top nut and so would still have ~4.5mm min of threaded steer tube . .

If I understand correctly all you'd need is a few extra washers.

here ya go...


http://store.velo-orange.com/index.p...t-spacers.html

http://store.velo-orange.com/index.p...t-spacers.html


http://store.velo-orange.com/index.p...t-spacers.html

Usually the steer tube should be a max of 1mm shorter than the stack height (I think), but in this case the steer tube is 1.5-2.0mm short.

If the steerer tube seems to be short of the stack height, just make sure you have enough thread engagement so you do not end up stripping the top lock nut when you tighten it, or loosen and come off when you ride.
Ideally, you should have the steerer tube almost kissing the bottom of the inner flange on top of most locknuts which on most cases can be fine tuned with washers when your steerer tube is slightly longer than the internal stack height of the headset. but then usually, older bikes do not have their original headsets and the steerer tube was cut specifically to fit a certain headset stack height, thus sometimes ending up with steerer tube a bit shorter than a replacement headset's minimum stack height. If things are just loo to iffy, just be safe and get a different headset that can headset that will work with the steerer tube length best.

Chombi

that seems reasonable; as I mentioned there should be about 4.5mm of thread engagement (instead of a full 6.0-6.4mm) which seems sufficient, so I will put it on and see what it looks like in the end and make a call.