Can a frame designed to take an ahead headset take a quill.

[Captain Vimes]

The head tube is 120mm. Anyone know where I can look up what the steerer length needs to be and how much of that needs to be threaded? I have Googled, but struggling....

Ha! Think I have found it now, but wouldn’t mind some confirmation.

Head tube length, plus upper stack height, plus lower stack height, minus 2mm.

Sound right?

 

[foz]

Yes

 

[pigman]

I always worked on head tube plus 40mm is the length of the fork column. That then accommodates a high stack headset. If you then use a low stack HS add washers.
I would add don't work to a low stack HS. If you then want a different make with a higher stack you're kinda stuck

 

[Captain Vimes]

Thanks again!