jebensch

Hi Folks. I bought a conveniently large-sized Bob Jackson Super Tourer off local CL early 2016 and in the fall finally got it built up* nice-nice for my work commute.

I'm a big fan of the 90's Campy headset designs, so I snagged an Athena from Ebay and replaced the American Classic that was on the bike when I bought it. Removing the AC headset, I noticed the fork crown race came off easier than past headset changes I've made, and the top cup flew across the room with bang of the mallet on the removal prong.

So then installing the Athena, the fork crown race mounted too easily. It's not wobbly at all, no daylight, but it does turn around on its seat, and comes off with relative ease. Similarly, I was able to push the top cup into the head tube.

[IMG]50492004631__33787E04-D5F4-4211-8D07-2583F1670CAE by Jesse Strauss, on Flickr[/IMG]

I used my Sheldon press (threaded rod) to install the cups completely. I used red Loctite on the crown race and installed the whole cannoli.

So what do you think – is this a death trap? Or should I ride a few miles and if it the fork comes out of adjustment, then it's not meant to be.

Do I need to replace the whole head tube? That would be a bummer, but I'd do it if came to that.

Thanks for any advice, crew! -Jesse

*105 10-speed ergos, Shimano RD & cassette, Campy compact CX-11 crankset and Veloce FD. Some wheels.

Steve Whitlatch 

You can make a shim for the crown race to snug that up.

crank_addict

I surmise you've have the incorrect sized headset for application / fitment.

Measure and reference this chart:
Sheldon Brown's Bicycle Headset Dimension Crib Sheet

Once determined, perhaps post in the trade for thread to what you need or-

Not the most elegant solution but you could cheat and carefully shim. This would be a desperate measure and wouldn't advise for a fine bike. The headset is very critical part of a bike and affects handling, so use your best judgment.

Andrew R Stewart 

I'd ride it and see how it all works before doing anything major. LockTite retainer compound (use to be 609) is what I'd have used on the headset fit up. I've used this stuff a number of times over the years with good long term results. With the slip on but not loose fit you describe I doubt a shim would survive the install forces.


Remember that a headset is under compression when in use. So a slightly sloppy frame/fork fit isn't too grave a problem. Andy

Spaghetti Legs 

I recently ran across that with a Campy headset and I made a shim with a strip cut from a soda can. This was on a mid 80's Tommasini Air fork.

CliffordK

Look on the bottom side of the threaded bits (lock nut and upper bearing cup), and it should tell you the actual threading for your headset.

I think the "Italian" crown races are slightly larger than the "English" crown races, wile the English/Italian threads are close.

I doubt your fork will fall off due to a loose crow race. But, it could wear a bit.

JIS bearing cups will also be small. I have those in one bike, and so far I haven't lost my fork. However, I doubt your Campy parts are JIS, unless someone had turned them down to fit an odd frame.

Actually, if the bottom cup is tight, and the top is loose, I'd take the top race out, and carefully inspect for cracks in the headtube.

JohnDThompson 

I'd use something like this:



LOCTITE Bearing Mount | JEGS

JohnDThompson 

This is another area where we are blessed with multiple standards:


Source: Sutherland's 4th Edition

CliffordK

So, subtle differences from the Sheldon Brown website.

Sheldon Brown's Bicycle Headset Dimension Crib Sheet

Although Sheldon Brown uses ISO which I had thought was English and is only showing the 30.0 bearing cups in the JIS.
27.0 crown races are really loose on a fork designed for 26.4/26.5

I had a heck of a time pressing the crown race onto my Colnago C-40 fork, so I assumed it was the 26.4/26.5 issue.

Charles Wahl

Welcome back to BikeForums C&V, Jesse.

jebensch

Thanks, Charles! Nice to see familiar names and bike parts.

jebensch

I looked for 609 at a couple hardware and auto parts chains around. No luck. At Auto Zone the kid who works at all the fast food joints on The Simpsons was baffled by my inquiry. I figured I could order it off Amazon but was too impatient and used the red threadlock I already had.

Per the above suggestions though, I might disassemble again to check for cracks in the upper head tube, then reassemble with 609 on the crown race and upper cup.

I still have a couple weeks before I need it ridable for work.

T-Mar

I find aluminum shims (i.e. soda pop cans) too soft. I make my shims from 6" stainless steel feeler gauges purchased from automotive supply shops. In addition to being more durable, they're available in a wide selection of thickness, to suit the particular application.

exmechanic89

This is what I would do as well. If the headset stays afjusted properly and you dont get any play or weirdness, I would use it as is.

jebensch

Very good to know, thanks T-Mar!