[frogmeetcog]

Not really sure which category this would go in, but I suppose this is about the level of knowledge required. I am looking to prove either the existance of a part (hooray for me) or be reasonable sure it does not exist.
OK.
As External Bottom Brackets are now in fashion, I was wondering if any manufacturers are making external headsets by now.
This occured to me recently as I have a beloved old frame that I have logged many a zipcode on, and was looking at the 1.125" disk fork sitting there in my garage, unused. My old frame has a 1" headtube, and the corresponding fork has finally breathed its last. With just the bare headtube, no bearing cups, the disk fork's steertube fits through the frame's headtube with a bit of space left. I know full well that that is not enough space for bearings that would last any decent amount of time. However, if there were a headset that puts the balls/rollers/needles outside of the headtube, it would certainly work, provided the cups are the right size.
Now, granted, there are used frames, forks, and headsets to be found cheaper than what this might cost me, but I am attached to the old thing, and I would like to use it some more. Also I would relish the perversity of having a disk fork on it....

 

[mtnbiker72]

I was wondering if any manufacturers are making external headsets by now

Wow...really?

External bearing headsets have been the norm for at least 100 years. It has been recently that internal (integrated or zero stack) bearing headsets have become common.

But no, your 1.125" fork will not work with a 1" headtube...you still need space to press the headset cups in the headtube. Just as external bearing BB's still need to be threaded into the Bottom Bracket shell

 

[theextremist04]

do you realize you won't be able to even get the steerer tube through the frame?

 

[frogmeetcog]

thankyouverymuch mtnbiker72, I guess that was a moment of neural flatulence.... internal headsets are the present fad, I did forget. I just held the end of the 1.125" fork steerer inside the bare 1" headtube, and from my rather optimistic eyeballing, for lack of accurate callipers, it seems like there is about 1.5 mm or so to spare (I don't have a good eye for inch fractions).
The flange on an aluminum headset cup would defiinitely fail if machined as thin as .66667 of a mm (then again I could be way off by now with my math which was fudged to start with) and so would a mild steel one probably, but perhaps a stainless cup might still be functionally sound, if anyone bothered to make those. I have some random stainless steel plates in my garage that defy any attempt at cutting, drilling or filing them, and make using a benchmounted grinder a bit scary, so I think that stuff might resist that kind of sheering force.
That would be actually pretty smart, for a suspension mountain frame that is heavier than any road bike (besides the infamous Varsity) that is used for rock/stump/cliff bombing, perhaps a headset that is actually made of a bombproof-though-kinda-heavy material, rather than just Al made ever thicker....

 

[frogmeetcog]

I am trying to think of what caused this uninformed spasm of redundancy. Then again, look who is responding to it. Ok, on your level:
__________________________________________________________________________
do you realize that I just put the 1.125 steerer tube through the 1" frame a few minutes ago to measure how little wiggleroom it had?
are you sufficently rich that a) the bikes you ride all have 1.125" headtubes or bigger, and when they do break, rolling down the pavement after years of similar sporadic, fariweather use, you call a cab and pay someone to fix them
or b) I don't know what the smeggin other option besides ignorance of one's bicycle would be, so I shall stop this mootity (mootness?) now.

Gawrlk, that struck a nerve.

 

[mtnbiker72]

Well it would be interesting if you could get something to work. I know a 1.125" steerer will fit inside the headtube on a frame designed for a 1" steerer.

I know of Ti headsets, but stainless steel is not one I've seen. Maybe your on to something, It would be quite a accomplishment to make a SS headset...but other than cost it seems like it can be done.

 

[HungarianBarbarian]

You would need a special set of cups that pressed onto the outside of the headtube.

Stainless Steel Headset

 

[mtnbiker72]

Who are you responding to here?

 

[Slimpee]

It sounds like a pain plus the new fork will most likely throw the geometry way off on the old frame. Plus, old bikes w/ new forks look silly anyway, IMHO...

BTW, what kind of frame is it?