smontanaro 

I got my hands on a SunTour Superbe Pro headset last year with the intention to put it on my Griffon (intended to be full SunTour Superbe something). It had made do with a Campy Super Record headset, but you know, I just had to have this extra bit.

Over the winter I removed the Campy headset and went to install the Superbe. That was when the first weird thing happened. The crown race was a slip fit, not an interference fit on the 26.4mm fork. I left it loosely assembled and hung it back up in its winter hiberation spot. I recently purchased a couple spring-loaded center punches, and carefully created 16 pretty evenly spaced dimples. That solved the loose crown race. When in place it was nice and level.

I buttoned everything up and adjusted it, in essentially the same way I'd adjust a Campy or other classic headset. Took it out for a test ride only to find the headset acted as if it was loose. If I hit a bump or rocked it back and forth while stopped with the front brake engaged, it was clear it was too loose. So, yesterday I took care of that, tightening it up a bit. Now all the play is gone, but it's really pretty tight. It doesn't seem like there's a "just right" spot.

I took it out for a test ride this evening. I'd never realized how much subconscious brain and motor activity goes into riding a bike in a straight line. With the tight headset the miniscule subconscious adjustments weren't really enough, and little side-to-side movements got a bit bigger because the tight steerer slowed the bike's response. It thus required more conscious brain activity to keep a straight line. Only not really. It wasn't like I was riding drunk, all over the road. It was more like I was a little tipsy. I've never experienced anything like that. (I don't drink, so there was no residual ethanol in the tank.)

I can swap the SunTour part back out, but I'd like to make this work. It's got seals, so I wonder if this is like some other sealed bearing type applications where a bit of break-in is required.

juvela

-----

it is certainly puzzling since you report everything operated smoothly with the Campag in place

if for example the milling of the head tube or fork crown race seat were off it would have shown up with the Campag
so one would think this eliminates them as possible source(s) of difficulty

the presence of seals might indicate the Superbe headset was provided by Hatta

you do not mention if you are using the retainers which would have come with the Superbe or if you went to loose ball

shall look forward to reading the observations of those with better minds...


-----

clubman 

Sounds like a JIS crown race.

repechage

I too think the crown race is a poor fit, allowing the axial play. Measure the crown race in comparison to the Campagnolo part.
Also, a small detail overlooked often, Campagnolo notes to perform final adjustment with the stem in position and tightened up.
most of the time I use a like stem set at the same height without bars so that I am not adding the other mass to the system.

mpetry912 

Skip if the crown race is loose you can use your automatic center punch to put a couple small "dimples" in the crown to create some interference.

As stated above do the final adjustment with the stem installed.

I think you'll have a hard time finding an alternate sized Superbe crown race as a piece part.

another thing you might try is confirm that the head tube is milled correctly so as to have both ends parallel ? only way to do this is to use the HS mill and just kiss the head tube.

/markp

Reynolds 531 

Triple check, because of the prolonged winter assembly, that a bearing is not inadvertently upside down.

dddd

I wouldn't expect mere dimples in the steerer's seating area to sustain the loading during use. The dimples just help with centering the crown race so that some Loctite can set up with the race centered on the steerer. I've known even Schwinn's vertical steerer knurling to become loose fitting with the crown race on low-mileage bikes (both of my early-70's Supersports had this issue, their original forks may have been sub-contracted).

An upside-down bearing retainer is something that I've come across on just every type of ball bearing on a bicycle over the years. I made this mistake myself as a six- or seven-year-old (discovered my mistake only five or six years later) when out of curiosity I had rebuilt my first front hub while repairing my first bike's flat front tire.


Editing here;

It's possible that the wrong retainer(s) was (were) used, since there are so many different sizes with only subtle differences!
Sealing rings can also be reversed, or upside-down. Or incorrect parts.

Possible also that said "wrong ball retainer" has the wrong-sized bearing balls for the headset(?).

Roller bearing headsets with separate thin races can easily be installed with a race off-center, and which then becomes damaged.
I even had one go off center on it's own after riding a lightweight bike off road (no, the headset had not loosened first, just 531 steerer flex)!

I've come across two OEM steel headsets in all my years (low-end 1980-ish Bianchi and 1974-ish Viscount Aerospace Sport) which had machining defect(s) such that the mating parts (races) touched each other where a gap should have existed when adjusted to the needed tension. Very rare (and would be rarer still on higher-end parts). Stuff does happen however.

Hopefully also that the steerer hasn't perhaps been bent and then straightened by a non-framesmith individual.

Various bikes I've owned had parts of the handlebar's rotation arc where the bearings tightened up, presumably the result of an un-faced head tube.

Tightening the stem quill shortens the steerer slightly, adding to the bearing tension pre-load.

smontanaro 

Took me a few days to get back to this. I'm still befuddled. Things I have checked:

• Before I originally installed the fork crown race, I measured it. I saw no reason to believe it was way oversized. As I indicated, it was a slip fit, not an interference fit. It certainly wasn't a 27.0 race. There's also no play after dimpling. I believe it's going nowhere and is properly centered. I could, in theory, add some Loctite, but I doubt that will change things.
• I took it all apart today other than removing the fixed bits. The retainers each contain 22 5/23" bearings. Placed on the respective races, they appeared to be to sit where they should (re: dddd). They also appeared to be correctly installed in the upper and lower cups. They came to me with bearing retainers and seals installed. I disassembled them today for the first time (since being in my possession).
• With the stem out and a clamp holding the front brake tight, if I rock the bike back and forth, the play is clearly at the top end. I didn't notice anything at the bottom, but will double-check that when I get back to it again.
• Per dddd's comment, when it's tight, it's tight all the way through the turning arc. It doesn't just bind in one place.

Note that I started with a properly functioning system. I'm certain nothing is bent. I responded to an ad on the C&VFS subforum (back in 2018). I built it up with parts on-hand. That included a Campagnolo Super Record headset which never gave me any problem. The only reason for the swap was to increase the fraction of parts on the bike which were SunTour Superbe/Superbe Pro. I can certainly go back to the more pedestrian Campy part.

dddd

One bike that I had worked on had a similar sort of problem, turned out there was a bearing ball stuck to the inside of the head tube with grease that caused interference between the steer tube and the inside of the head tube.

Piff 

I can't imagine how annoying it was to troubleshoot that only to find a single errant ball bearing...yeesh.

zukahn1 

This may seem odd but try new top end set of raced bearings about $20 will likely fix stuff if not put them in the Campy stuff and mix match a bit if needed having a bit mashes up head set is no big deal. End off the day it's about the bottom race seat good you can run slightly loose set till the bike wears out . I have bikes with 50 year old French junk head sets that are fine.

smontanaro 

I'm closing out this episode without resolution. The Super Record headset which worked well before has been reallocated to my new bike. I grabbed a Specialized sealed bearing headset from the stash and installed it this afternoon. As far as I can tell, it's going to be fine. I will ride the Griffon tomorrow to confirm.

Just to confirm that the headset wasn't the incorrect size, once I removed all the bits, I inspected then as I was cleaning everything. They were all stamped 26.4 or 30.2. It's possible something was out-of-spec somewhere (maybe one of the races were ground at an incorrect diameter?). Oh well, I guess I'll save it for parts or move it along to someone else who wants to play with it.