I replaced a headset on my Bianchi a few months ago. I had to cut the steerer tube to get it to work and now i want to upgrade my headset. What seems to be the problem is stack height, the one on it now is has a stack height of 30.2mm i believe. All higher level ones are around 37mm or 38mm will the 7 or 8 mm difference be a problem or would it just translate to a reduction in thread contact?

thanks in advance
John

threaded or threadless?

Cane Creek 110 is 28.6mm stack height. cost @ msrp=$150

He has threaded, as stated.

Do you have 7-8mm of spacers right now? There are threaded headsets that have a lower stack height than 30.2mm. Cheaper Tange models spring to mind. You'll want at least 2-3 threads of engagement on the top nut.

my mistake, it wasn't stated overtly.

Unless you have a suitable spacer between the top race and the lock nut or you can find one of the Tange low stack height threaded headsets, you are hosed.

Loose Screws has a Ritchey 1" threaded headset with a 33 mm stack height:

https://www.thethirdhand.com/index.cg...d=839136630460

Bike Tools Etc also lists Tange Levin headsets but they also have a 33 mm stack height:

https://www.biketoolsetc.com/index.cg...ts&tc=Threaded

Even these probably have a stack height too much for your steerer if it was cut to exactly work at 30.2 mm.

I have a '92 Trek 1420 Trek which, for reasons known only to Trek, the steerer was factory cut to EXACTLY fit a Tange OEM headset. I was able to fit an Ultegra loose bearing headset as a replacement with the same 30 mm stack height. But, when the Ultegra went belly up (in 15,000 more miles, btw), I couldn't find any current threaded headset that would work except a Chris King.

I wound up upgrading the bike to a threadless fork, headset and stem for about the same money.

The Tange Passage is what i'm primarily thinking about. Our shop stocks that and the levin model, both have super low stack height. THe passage is rated as 30.3mm which I think can actually be lowered further if you lose the spacer, which will make it around 28mm.

I'm not aware of any other options except for finding older NOS shimano threaded headsets with their super low stack heights.

e.g: https://www.jensonusa.com/store/produ...d+Headset.aspx