dura ace headset
 

Would a Dura Ace 7700 headset be replaceable with a Dura Ace HP 7410 series?They both are 1 inch and the 7410 is 24TPI(whatever that means)Thanks!I need a new headset!

yes you can change one for the other . TPI means thread per inch. the 1 inch mean the size of the steering tube on the fork.

stack height compatible?

How do I determine stack height?

take the headset off the bike , stack the parts on a table in the same order, use capliers or a ruler and measure. if the new one is the same or smaller (shorter) then all is good. if not you need a longer steeing tube on the fork . or new fork.

This assumes the portion of each cup that is pressed into the headtube is the same height, right? I would have expected some variance between different headset models.

The HP-7410 is a 1" threaded headset with cartridge bearings and has a stack height of 37.6 mm.

I can't find any reference in Shimano's tech documents to an HP-7700 headset but they do show the 7410. Also, I don't recall Shimano making anything newer than the 7410 version and by the time the 7700-series (9-speed Dura Ace) came out, Shimano was pretty much out of the headset business.

Maybe that's why I don't find a 7700 headset on e-bay!!