Head tube-headset tolerances in CroMo frames

[IbocProSX]

I've done it again, in a typical impulse buy I acquired a modern CroMo frame & rigid forks with a retro twist to it. Well, on fitting up the headset my King headset installed in the headtube with mild hand pressure only (very mild actually). It doesn't rattle but I'd call it a "slip fit" at best.

The King came from my Foes, no fit issues and was removed with proper tools. Foes has a rather sturdy headtube that gripped fine. Previous owner had a Cane Creek S8 in the steel frame, removed with proper tools too. I picked up the frame in person, no doubts he's an enthousiast and sincere. He suggested I try another headset for size and I did: low and behold, the Race Face Deus I tried (designated for another build) does not go in with hand pressure only.

So what's up? Are King cups on the small end of the tolerance or could the S8 have been big, or could it be the head tube is out of spec? Or is it all so tight in steel that this is something that can happen ? Never happened on an aluminium frame since 1992.

Thanks in advance for any help

And this is a picture of the new project, notice anything special BTW?

 

[Andy R]

Get a micrometer and measure the headsets to see if there is any significant difference between them - presumably there must be?

Nice frame (Surly 29er?) but BIG :roll:

 

[Elev12k]

Had it a Campa headset fitted before?

Anyway, Locktite has some products to proper fit cilindric bits. Try 668.

 

[IbocProSX]

It is a logical step to measure, but correct sized micrometers for internal and external measurements I struggle with. A set of calipers (schuifmaat) I can manage, but likely is not accurate enough. The headset cups are ok but the differences are small and the head tube ends will be difficult to get right.

I think it will be even more difficult to draw firm conclusions from the data. Instead I was hoping to draw on the experience here and see if this is really extraordinary or not. See if I get replies of other loose" headsets. And I wiull cjeck if a Campa has been fitted previously, they'll probably remember it was difficult to fit/remove.

Bonus points for your keen eye Andy: BIG 29er indeed, but not a Surly it's a Singular Swift. Paint is not original, I'm not sure what I will do with it but first plan is a silver themed build on the current paint.

 

[perry]

had the same thing on a brand new steel frame and brand new king , both bought from the same shop i whole heartedly trust ( mate worked there )

i was all ready to bash it in too

since then the king has been in my standard bmx ( waterford precision cycles made ) and my terrible one bmx , both of which requiring significantly more effort to fit

its now sat in my dmr and just pushed in

why buy a king and then question its quality :roll: and surly face their headtubes after welding

the mid and spanish size of bottom bracket bmx uses now only requires moderate hand pressure to fit

 

[Tallpaul]

I had exactly the same thing with a King headset and a Kona Hei Hei.

I installed the cups with my hands and just a light tap of a rubber mallet to seat them, it was great!

I haven't had any issues with it since fitting the forks and stem and setting everything up.

 

[perry]

it makes lining up the "kings" easy

there isnt any need for the cups and tube to be a dificult fit anyway , just as long as its not loose

 

[longbeech]

I've had all sorts of variables when fitting headsets from almost cracking the headtube on an ally frame to a really loose fit on my marin East peak.

I think its just down to manufacturers machining tolerances but when you can find one that slots in just so with no play it makes the job so much easier.

 

[messiah]

I had a Nicolai hardtail that a King was a loose fit in. The frame had previosly had a Hope which were notoriously on the large side. An FSA orbit extreme was a perfect fit so the King got sold onwards.

 

[IbocProSX]

why buy a king and then question its quality

I do not question it's quality, only it's size
And the other reactions indicate it is not that uncommon

it makes lining up the "kings" easy
.... , just as long as its not loose

Lining up was a doddle indeed, and though not loose I am a little worried that with the extra long lever of the suspension corrected 29er fork it will become loose over time. There may be insufficient clamping force on the cup to resist some rocking motion.

This is where the Loctite suggested by elev12k may provide a solution. It will also depend whether I end up taking it off-road proper. For now I have some Mavic SpeedCities and CX tires lined up for it.

Enjoy!!