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-   -   Guerciotti BB Crack? (https://www.bikeforums.net/classic-vintage/1181563-guerciotti-bb-crack.html)

nomadmax 08-19-19 04:00 PM

Guerciotti BB Crack?
 
I recently came across a Guerciotti that I think is made of Columbus SL tubing. What concerns me are the visible cracks in the paint and possibly the BB shell pictured below. I know of one other bike from this batch of frames and the owner is a member here. I'm looking for opinions as to how to proceed, ie the seller may get this bike back. The only thing that has me holding out hope is that there's cracking like this in the paint on other parts of the frame, however, it isn't this pronounced. Thanks in advance.

https://cimg1.ibsrv.net/gimg/bikefor...9227c211ad.jpg
https://cimg5.ibsrv.net/gimg/bikefor...dc2eb6a8ea.jpg
https://cimg0.ibsrv.net/gimg/bikefor...d1be045d15.jpg
https://cimg5.ibsrv.net/gimg/bikefor...9cadd77c09.jpg
https://cimg9.ibsrv.net/gimg/bikefor...a7209ad839.jpg
https://cimg3.ibsrv.net/gimg/bikefor...8e133fcaf5.jpg

Trevtassie 08-19-19 04:09 PM

It does look like they went hard with spray putty and paint, too thick, and that could explain the cracking, since there is cracking away from the lug, but then the main crack is right in a suspicious place. Only way to find out is to get that paint off. Which is probably a good idea anyway, since water and salt can collect under it and start rust anyway.

Drillium Dude 08-19-19 04:30 PM

I believe that is simply brittle paint cracking under normal BB shell stress. I'm sure someone will come up with a pic that proves me wrong, but every time I've seen a joint fail it's been the tube that cracks/breaks, not the lug or BB shell. It makes sense, as the tubing is much thinner than the shell or lug.

I've never, ever seen or heard of a shell cracking/failing like this. There's always a first time, of course. Take a careful test ride if you can, see if you can detect anything.

If that's original paint, I'd hate to take it off in the area of the crack just to disprove what is extremely unlikely. If it's truly cracked, a short spin around a parking lot should give you the answer.

DD

merziac 08-19-19 05:57 PM


Originally Posted by Drillium Dude (Post 21082848)
I believe that is simply brittle paint cracking under normal BB shell stress. I'm sure someone will come up with a pic that proves me wrong, but every time I've seen a joint fail it's been the tube that cracks/breaks, not the lug or BB shell. It makes sense, as the tubing is much thinner than the shell or lug.

I've never, ever seen or heard of a shell cracking/failing like this. There's always a first time, of course. Take a careful test ride if you can, see if you can detect anything.

If that's original paint, I'd hate to take it off in the area of the crack just to disprove what is extremely unlikely. If it's truly cracked, a short spin around a parking lot should give you the answer.

DD

If the BB is actually cracked it should be detectable from the inside, BB R+R would be easier than paint hack. ;)

RobbieTunes 08-19-19 06:02 PM

It does look like it might be Imron or some other acrylic.

I bought the same seller's other bike, but I've been through the frame, and it's fine.
For the Gerk, the seller and I corresponded when he first got it, to get it rolling.

Sir_Name 08-19-19 06:15 PM

That’s interesting. Could the DT/ST/BB shell joint have been compromised somehow, leading to extra flex and strain at that joint? Then over time the tubes and paint flexed enough to lead to what’s seen here?

I’m not saying that’s what happened necessarily, just a worst case to inspect and pick at.

The paint does tell a story.

embankmentlb 08-19-19 06:17 PM

I agree with what was stated above, check the inside of the bottom bracket. It may only be bad paint. https://cimg4.ibsrv.net/gimg/bikefor...052f37135e.jpg

merziac 08-19-19 06:19 PM

Either way it's nasty or toast. ;)

nomadmax 08-19-19 06:34 PM

Thanks guys. I'll pull the BB and tomorrow and post back the results.

Here's my next question:

It's gonna need to be completely stripped and repainted. Based on the bike's history it has to be done in the same colors/setup. I'll have them cold set the rear to 130mm and probably have the cable guide braze ons moved from the top of the top tube and have a couple stops added to the side.

Who to send it to? Off the top of my head I think Allan Wanta but Jack Trumbull @ Franklin is semi local to me. Others to consider ?

gearbasher 08-19-19 06:38 PM

I've seen two bottom bracket shells that cracked completely around the seat tube lug. So, you might want to inspect it.

A friend had the seat stay on his Masi re-brazed to the seat cluster and a total repaint done by Franklin Frames. It was beautiful.

scarlson 08-19-19 06:58 PM


Originally Posted by Drillium Dude (Post 21082848)
I'm sure someone will come up with a pic that proves me wrong, but every time I've seen a joint fail it's been the tube that cracks/breaks, not the lug or BB shell. It makes sense, as the tubing is much thinner than the shell or lug.

You called it :)

https://cimg5.ibsrv.net/gimg/bikefor...c5781a0b0d.jpg

This is from my thread about my commuter Holdsworth/Claud Butler. The bronze braze filler didn't penetrate all the way through under the lug, so the lug cracked due to fatigue. While economics/pricing suggest that a Guerch' shouldn't suffer from this sort of bad workmanship, you never know.

In addition, if it is a crack in the lug due to bad brazing, the tubes beneath should not be cracked. This means that you wouldn't be able to tell by looking inside the bottom bracket.

If you are going to strip and repaint it anyway, why not file/chip away the paint there to investigate?

nomadmax 08-19-19 07:05 PM


Originally Posted by scarlson (Post 21083076)

If you are going to strip and repaint it anyway, why not file/chip away the paint there to investigate?

This bike may be going back to the seller. I can't remove the paint. Once I do it's mine forever.

merziac 08-19-19 07:12 PM


Originally Posted by scarlson (Post 21083076)
You called it :)

https://cimg5.ibsrv.net/gimg/bikefor...c5781a0b0d.jpg

This is from my thread about my commuter Holdsworth/Claud Butler. The bronze braze filler didn't penetrate all the way through under the lug, so the lug cracked due to fatigue. While economics/pricing suggest that a Guerch' shouldn't suffer from this sort of bad workmanship, you never know.

In addition, if it is a crack in the lug due to bad brazing, the tubes beneath should not be cracked. This means that you wouldn't be able to tell by looking inside the bottom bracket.

If you are going to strip and repaint it anyway, why not file/chip away the paint there to investigate?

The tubes at that juncture would be mitered and likely would show the crack in the BB shell, easy enough to examine, I would already have it done one way or the other.

cudak888 08-19-19 07:38 PM


Originally Posted by nomadmax (Post 21083088)
This bike may be going back to the seller. I can't remove the paint. Once I do it's mine forever.

Pull the BB. Shine a REALLY bright pen-style LED light into the gap. Do you see light?

If not, build up some non-hardening putty around the "crack" to make a water-tight valley. Fill it with water, WD40, or whatever cheap liquid you have in mind that won't soften or destroy the paint. Does any seep through?

If it passes these two tests, you have one more thing to ask yourself: How much frustration are you willing to deal if/when you finally decide to part with this one? You're going to get a ton of buyers who won't accept this crack; either out of fear, distrust, or general dislike of how it looks, or what it seems to look like.

-Kurt

unworthy1 08-19-19 08:44 PM


Originally Posted by cudak888 (Post 21083143)
Pull the BB. Shine a REALLY bright pen-style LED light into the gap. Do you see light?

If not, build up some non-hardening putty around the "crack" to make a water-tight valley. Fill it with water, WD40, or whatever cheap liquid you have in mind that won't soften or destroy the paint. Does any seep through?

If it passes these two tests, you have one more thing to ask yourself: How much frustration are you willing to deal if/when you finally decide to part with this one? You're going to get a ton of buyers who won't accept this crack; either out of fear, distrust, or general dislike of how it looks, or what it seems to look like.

-Kurt

I agree with this approach, and if you document the testing (phone videos) and you got positive results (of course) you might dispel the fears/doubts of SOME future buyer who doesn't appreciate original "patina".
BTW, for the record DuPont Imron is/was 2-part (or "2-pack") polyurethane, not acrylic.

scarlson 08-19-19 09:24 PM

Yeah, and WD40 is probably safe for the paint. I regularly use @cudak888 's above-mentioned approach to check cylinder head valve seat leakdown. But there I can use plain guzzoline or acetone, which might touch the Imron. WD40 is a likely-safe substitute.

delicious 08-19-19 10:08 PM

I have lots of questions, if you don't mind:

Where can I find this seller? Do they still have more of this "batch?" I didn't see these advertised in the classifieds.

Did you get that Gainesville jersey with the bike? Was this paint job designed for Gainesville Schwinn?

Thanks!

embankmentlb 08-19-19 11:57 PM


Originally Posted by delicious (Post 21083335)
I have lots of questions, if you don't mind:

Where can I find this seller? Do they still have more of this "batch?" I didn't see these advertised in the classifieds.

Did you get that Gainesville jersey with the bike? Was this paint job designed for Gainesville Schwinn?

Thanks!

The bike and the jersey are part of the original team kit from the North Georgia Wheelman team. There were 10 to 15 of these custom painted bikes ordered from TSD. I designed the jersey and picked the paint colors for the team. This was way way back before things were done by computer.
I know of two others that still exist. This is the first one I have seen for sale in many years.

verktyg 08-20-19 02:11 AM

Cracked BB Shell ???
 
The area in @nomadmax frame was a weak spot in some brands of BB shells because the sharp V could create stress risers which would lead to cracks.

On some better built frames, extra brazing material is added to that area from inside the BB shell to fill any gaps.

TSD? That frame most likely came into Ten Speed Drive Imports unpainted. They received a lot of Italian frames that way. They claimed that the Italian paint jobs were poor quality and they could do better themselves in house.

The "DayGlo" fluorescent colors are sprayed over a white base coat then clear coated. The "craquelure" finish looks to be mostly in the clear coat which has shrunk over time.

@cudak888 I like Kurt's suggestions on how to test for a crack in the BB shell.

It's DayGlo NOT NEON!!! You can still buy DayGlo paint but you may have to buy it in a gallon size for each color: https://www.dayglo.com/

We sold a number of Guerciotti frames in the mid to late 70's. We had to warranty a few of them because they cracked across the BB shell. They had a sharp 5 pointed star cut into the bottom of the BB shell which created stress risers.

We may have been getting those first frames through Gus Betat in New Orleans. The problem was soon rectified by using rounded points on the stars (like on nomadmax's frame) Later frames came from TSD. For some reason, most were fire engine red.


BB crack on another frame???

In 2010 I picked up a 1985 Raleigh USA Reynolds 753 Team Pro bike made in the UK by Raleigh's SBDU. It had been raced by sponsored teams in the Northwest and passed around for a few years. The frame had been resprayed (probably a factory job) in 1992 Raleigh USA Team Technium Kit.

What it looked like when I first got it with a worn out Suntour Superbe Pro gruppo.

https://cimg2.ibsrv.net/gimg/bikefor...4d7e2364af.jpg

As I was replacing the BB, I got sick when I noticed what looked like a crack at the down tube, BB shell.

https://cimg6.ibsrv.net/gimg/bikefor...807f6c6785.jpg

I took it to a frame builder friend and he thought that it was in the braze not the down tube. He said that he could do a slight fillet around the BB and tube or replace the whole down tube. He recommend that I mark the ends of the "crack" and ride the bike to see if it got worse.

I used a Sharpie pen to mark the ends. That was 9 years ago. So far nothing has changed. Knock on wood.

https://cimg0.ibsrv.net/gimg/bikefor...56ade996a6.jpg
https://cimg1.ibsrv.net/gimg/bikefor...26965c9772.jpg

verktyg :50:

RobbieTunes 08-20-19 04:11 AM

I like that it's getting hopeful.

3Roch 08-20-19 04:49 AM

Perhaps better than using water etc or a light to find a crack ( the crack could be full of crud).

When you have the BB open plug up any holes in the frame including other side of the BB, rig up a BB size plug on the air chuck on your air compressor, put some soap water over the suspect area and put some air pressure (don't need much) inside the frame. No bubbles= good, bubbles= bad

cudak888 08-20-19 05:10 AM


Originally Posted by 3Roch (Post 21083484)
Perhaps better than using water etc or a light to find a crack ( the crack could be full of crud).

When you have the BB open plug up any holes in the frame including other side of the BB, rig up a BB size plug on the air chuck on your air compressor, put some soap water over the suspect area and put some air pressure (don't need much) inside the frame. No bubbles= good, bubbles= bad

That might be tough sticking corks into both the downtube and top tube, but it's not a bad idea if the aforementioned tests come up inconclusive.

-Kurt

nomadmax 08-20-19 05:17 AM

I pulled the BB and took a few photos. There was a fair amount of crap inside the BB shell as the previous owner used body masking tape to cover the star cut out on the outside as well as inside during his restoration, he even clear coated over it. It looks like the interior of the tubes still have the protective coating and rust doesn't seem to be an issue. I did find a dent in the right chainstay that isn't present on my 84 Guerciotti SL so it will need to be replaced.

I'm going to shoot off a couple emails to two frame builders/painters and get a ball park idea what it'll take to bring the bike back. In the meantime, when I get time, I'll get an endoscope camera look inside the BB and hopefully between the mitered seat and down tubes where the crack would be. I'll also try the liquid test as well. The good news is I can't see any light coming from the BB shell to the outside and I don't see any evidence of witness marks on the tubes indicating there has been movement. Not 100% but certainly encouraging. I'm not budgeted for this kind of time or money right now and based on the seller's assurances I had no reason to think I'd have to be.

I was originally scheduled to drive down to GA and pick up the bike in person; a couple days before, the seller suggested Bike Flights as a better alternative for both of us. My gut told me no but I agreed after asking for and getting more pictures of the frame. The close ups he sent were of every place on the frame but the areas of concern, most notably the BB shell. Had I seen the bike in person I would have walked away, this is 100% my fault for not following my instincts. Right now my gut tells me to drive it to GA and get my money back but I'm not decided yet. I've gotten some great deals in the C&V world so even if this thing turns out badly it still doesn't diminish the overall experience of the hunt and chase. Sometimes you get the bear and sometimes the bear gets you. Guerciottis hold a special place for me because I raced them, I'd probably go further than the next guy to bring one back. This one, given it's history and having actually talked with the guy who designed the colorway and jersey deserves to be put right and out on the road.

https://cimg6.ibsrv.net/gimg/bikefor...2aef3d4e56.jpg
https://cimg0.ibsrv.net/gimg/bikefor...ffaf2d0ed9.jpg
https://cimg2.ibsrv.net/gimg/bikefor...861bacbefe.jpg
https://cimg7.ibsrv.net/gimg/bikefor...b1672bcb8a.jpg
https://cimg0.ibsrv.net/gimg/bikefor...2c31ee5973.jpg
https://cimg8.ibsrv.net/gimg/bikefor...7023d8f231.jpg

verktyg 08-20-19 05:19 AM

Soapy Water For Testing Gas Line Leaks
 

Originally Posted by 3Roch (Post 21083484)
Perhaps better than using water etc or a light to find a crack ( the crack could be full of crud).

When you have the BB open plug up any holes in the frame including other side of the BB, rig up a BB size plug on the air chuck on your air compressor, put some soap water over the suspect area and put some air pressure (don't need much) inside the frame. No bubbles= good, bubbles= bad

Mix 1 tablespoon of dish washing detergent into 1 cup of water to create a leak detecting solution. You can also buy a thick commercial solution that does the same thing.

Paint the solution over the suspected crack and apply air from inside the BB shell and look for bubbles coming out.

verktyg :50:

verktyg 08-20-19 05:36 AM

Heavy Respray
 

Originally Posted by nomadmax (Post 21083499)

It looks like the BB area has been resprayed, as if a repair was done in the area???

Does the paint look like it's been blended in like around the BB and/or is there cracking in the paint in any other area of the frame?

If not then you may have an answer to your question about a crack.

Also, there is a smaller ding behind the dent in the DS chain stay. Dents like these are not normal and can come from a severely jammed chain???

verktyg :50:


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