Headset with 28mm stack height...

[FluffyChicken]

That comes under the bodge something up*. (that locknut is the same/similar to the Growler one of old)

Over to the BoyBurning though

Just checked bikepro threaded headset stack heights and the DiaComp threadset of old came in lowest at 29mm.

* As long as it can push the compression wedge thingy or whatever crankbros used then it should be fine. A normal compression wedge might not like the threads being there (it would dig in to them) ?
But be interesting to try.

 

[gtRTSdh]

That comes under the bodge something up*. (that locknut is the same/similar to the Growler one of old)

Over to the BoyBurning though

Just checked bikepro threaded headset stack heights and the DiaComp threadset of old came in lowest at 29mm.

* As long as it can push the compression wedge thingy or whatever crankbros used then it should be fine. A normal compression wedge might not like the threads being there (it would dig in to them) ?
But be interesting to try.

You're correct the taper ring would dig into the threads of the steerer tube first, however the steerer tube could be wrapped in steel shim, say 0.15mm / 0.006" thick to avoid this and allow the taper ring to slide down the steerer tube freely.

 

[danson67]

This ahead's down to 18.5mm :shock: That would give you 10mm to play with on the whole top cap/locknut part...
http://www.euroasiaimports.com/productcart/pc/viewPrd.asp?idproduct=412&idcategory=431

Still looking...