Bad Lag

Start out knowing what is wrong. What if the upper edge of the lower head lug is brazed but just under-filled ? Jumping to the conclusion you have to do anything may be a mistake.

Is the inside diameter of the head tube uniform or bent out of shape?


What if this is all just paint damage caused by extremely ham-fisted installation of that cup.

Aerzon

I think I'll take it apart eventually and sort it out by inspecting the headtube, since I'm quite attached to this bike/frame and would like to know if anything does need to be done. I'll update this thread at some point.

The only thing is I have to get a headset press and sort out how to properly remove and install a headset. (I might as well as just replace it since the headset feels a touch indexed and I'll have it apart anyway)

merziac

I have a Nashbar press that is just like this, works great and isn't too bad $$$ wise.

https://www.ebay.com/itm/30412352240...EAAOSwYg5hl8G-

And this,

https://www.ebay.com/itm/26556132687...gAAOSw71RiFGWw

Lastly, you will need to remove the crown race, a bit tricky and can be done with a bearing splitter type tool but requires very careful setup to keep from damaging the paint.

The Park tool is $200+ but can make very clean work of it but you still have to be careful of the paint.

Installing the crown race can be done with a piece of pipe but of course they make a tool for that too and I believe it is worth the investment.

All these tools are seldom used for many of us but what they do is not easy to wrangle without a good process and at least some of them.

I also strongly feel that they are worth it so that you can complete an infrequent job like this with minimal aggravation and far less chance of damage if you have the right tools.

Fortunately I was able to assemble them over time for a fraction of the normal cost, I had also gotten by with other methods before that.

Or you can try and find a shop that will take it on but unfortunately now days few of them have the skill, even if they have the tools in good working order.

And your situation will require full understanding of the problem, therein lies the rub, if the problem is not assessed correctly, the fix may not be correct either.

Aerzon

Thank you for the summary. Once I get it apart, I'll likely post a picture if I find something that I'm unsure of as far as structural integrity is concerned. There's a lot of experienced eyes on here that are always a help.

Also, $200 tool to remove one part? Youch D:

merziac

Its actually more than that and I fully understand the sticker shock, that being said, one way to look at it is if you gack the paint, maybe the fork threads and or crown race seat and the still very serviceable Campy crown race, the value can easily exceed the cost in 1 or 2 times of using it.

Paint $100?
Fork/threads $50-100?
Crown race $50?
Crown race`seat $50-100?

Proper tools seldom used, prove their value by facilitating a successful task with less chance of problems.

https://www.parktool.com/product/adj...e-puller-crp-2

oneclick 

Depending on your level of skill and confidence, most crown races can be removed with little or no paint damage - with only a hammer and a bit of flat bar.
I use the centre section of one of those flat BB spanners, it's the right length and thickness and has nice square edges.

This only works if you have a portion of the crown race proud of (and normal to) the crown at the front and back of the crown; most do.

Kneeling, place the end of the steerer on something firm but yielding enough that it won't mar the steerer threads - a bit of hardwood will do.
Place the dropouts against your chest so you can hold the fork steady without your hands - you need them both for the next bit.
Place the bit of flat bar so that one edge rests on the bit of the race that is proud; hit the upper edge of the bar to drive the race off.
Rotate the fork, do the other side, repeat as required.
Done with care, the paint will be undamaged; if it's a particular worry drape a bit of thin cloth between the crown and the bar.

Road Fan

This is what I was thinking as well - plus, Ithink the photo shows the lower head tube lug and the head tube, not the top tube. In such a case where the crack might be miniscule but still a hazard, could Magnaflux be used to make cracks visible? (says Ken showing his age!)

Road Fan

This is where I'm at, and I may be facing (lol!) a similar problem on my Mondonico. I'd start with "clearing the decks" to make sure everything that might need to be seen can be seen. I would not reassemble without re-facing the head tube ends, possibly line-boring as well. On mine I haven't started it yet.

repechage

Good luck finding a machine shop to line bore it for a tolerable price. And keeping it to size.

merziac

You only want this done with proper HT reamer by someone that knows how to properly wield it, even if its not right, it may not tolerate much if any material removal before it becomes oversize and makes matters worse.

merziac

Prussian Blue dye check, messy and effective.

Road Fan

Actually I only expect to do it once or twice in a bike's life. At first I never did it, but then I found I could not get a replaced headset to align correctly (smooth rotation even with perfect bearings). Respected shop guy (there aren't many of those) chided me for not having the head tube and fork crown touched up. Unfortunately good guys retire and good shops close. I want to give business to the ones whom I can find.

And I don't have the correct tools for frame machining or alignment. I bought a used face reamer, but have not used it. It was supposed to come with at least its parts list and other literature, but I got nothing at the end of the day.

Road Fan

Well, fact is I have not had it checked yet or done any disassembly. It could be just cracked paint, so far.

Doug Fattic 

Aerzon, as a framebuilder, my guess is that the head tube for your frame was not properly reamed to the right size before the head tube cups were installed. Because the inside of the head tube is too small for the OD of the headset cup, it spread the head tube/lug enough so it cracked. Another clue that it was not properly faced (that has already been mentioned) is that the bottom of the head tube is not aligned with the cup. There is a bit of a gap.

Removing the headset, reaming and facing the head tube and fork crown is an easy job for a framebuilder. He can also determine if any rebrazingq needs to be done at the same time. Even if your lug is cracked, it is doubtful from a safety standpoint it needs to be rebrazed. However since you are there the framebuilder can give a better assessment than home mechanics looking at pictures on the internet.

SJX426 

Purchased tools are great when you expect to use them frequently. I made my own.
DIY Bike Tools on Flickr
The copper one is the head set cup removal tool.

BFisher 

Even the best of tools are useless in the wrong hands. And improvised tools can produce excellent results when used with care and attention.

I'm with SJX426. If I can't make it, I'll either spring for the tool or for the service at a shop. But if I can make it, I will. A functional bearing cup remover is pretty easy to fabricate. You can go all in with tool steel and heat treating, but it isn't necessary for infrequent usage. I used a length of 3/4" steel tubing, a drill, hacksaw, and a file on this one. It popped a very tight-fitting cup right out.


I've also made a smaller version to remove a pedal bearing cup by using the seat stay from a trashed frame. It worked exactly as it should have.

JohnDThompson 

I made one out of an old 1" steel seat post.

Aerzon

Bringing this thread back for a second. I have yet to disassemble the headset and lay eyes on the headtube, and I fully accept that this needs to happen. One of the concerns raised in this thread was that potentially the lower headset cup was fitting too tight/not seated properly, which could've stressed the headtube when it initially went in. I think this appearance could've been due to poor picture taking on my part+ some old grease around the cup giving the illusion of shadow and therefore excessive gap.

I retook the picture and cleaned this grease, I'm curious if this cup still appears to be seated improperly/not seated fully. For reference, I was curious to "measure" the gap in some way. I can't even appear to get a piece of floss in-between the seam formed by the headtube and crown. I know interpreting pictures online isn't the best, but I still find your interpretations valuable, since my eyes aren't very experienced with bikes quite yet.

merziac

Well you're right that it looks much better now from here and the floss thing is brilliant!

Now, like you said, get that cup out of there and get the frame under some harsh light for a good hard look.

repechage

Be sure to invert the bike when you take the headset apart, That headset I am pretty sure uses loose bearings.
with the stem out, caliper off and wheel out, check the headset adjustment for free rotation. mark and note the orientation of the cups, the appearance inside and feel will guide if leave them clocked as is or rotate.

Does look much better after cleaning.

Mad Honk 

I'm sticking to my paint crack assessment, and at this point I would say take a rifling file and cut a small bit of the paint at the bottom of the lug. If the lug is not cracked the cut into the paint will show that the lug is not cracked. Just the way I would do it. Smiles. MH