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Discussion Starter · #1 ·
So, I cracked the seat tube of my Giant XTC comp yesterday (even though I had minimum insertion on the stock seat post). Calfee says they can't fix it (which likely means they aren't willing to warranty it). LBS said they have never seen an XTC crack like that.

I am not the original owner even though I am the only one to ever ride it. Sucks.

So I am looking at work arounds. Any thoughts of which of these would be better?

(1) Drop and extra long 30.9 shim in and run with a smaller seat post?
(2) Epoxy an extra long seat post in and fix the seat post into place?

Any other alternatives or thoughts on the two above?

Thanks in advance.
 

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Write it off, and start saving for a new frame...
This.

If the seat tube is cracked, it'll keep cracking no matter what you do as a workaround, short of welding it up to stop the crack from growing. Then you might need the shim. And who knows what else, which is probably why Calfee said they couldn't fix it.
 

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Drill a small hole at the end of the crack. It will continue to propagate if you don't. Find yourself someone who TIG welds. Look at some of his/her work. If it looks good then hire them to do the weld. Shouldn't be more than $100 (free if the guy is cool).

A nicely done TIG weld will be hardly noticeable and will be good as new (stronger actually). Repaint if you want. Don't worry about sleeving unless it gives you peace of mind.
 

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So, I cracked the seat tube of my Giant XTC comp yesterday (even though I had minimum insertion on the stock seat post). Calfee says they can't fix it (which likely means they aren't willing to warranty it). LBS said they have never seen an XTC crack like that.

I am not the original owner even though I am the only one to ever ride it. Sucks.

So I am looking at work arounds. Any thoughts of which of these would be better?

(1) Drop and extra long 30.9 shim in and run with a smaller seat post?
(2) Epoxy an extra long seat post in and fix the seat post into place?

Any other alternatives or thoughts on the two above?

Thanks in advance.
Get some carbon and some epoxy. Sand the affected area. Wrap with carbon/epoxy [find some instructions online]. Let cure. Paint to make less F-ugly. Ride bike.
 

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Just an FYI if you weld a 7 or 6 series aluminum bicycle you would need to re heat treat which is quite a complicated process.

Assuming we're talking carbon fiber here, how far down is the crack? If it's not that far down the tube maybe consider cutting just below the crack & run a really long seat post. Pictures would help.
 

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So, I cracked the seat tube of my Giant XTC comp yesterday (even though I had minimum insertion on the stock seat post).
The markings on the post are the minimum insertion for the post, not the frame...generally speaking.
Can you post a pic of how far you had the seatpost in the frame?

There are other carbon repair places, I'm sure someone is willing to fix it if it's worth the $$ or not is up to you?
 

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It's very likely you've already gotten the best advice, which is get a new frame. Here's why. If there was enough stress on the carbon to create the cracks you found, then the material around the cracks has also been stressed to just below the point of failure. Now, it's very likely that the material that hasn't failed yet is nearly as strong still as it was when it was new. The problem is, you'd need some pretty high tech stuff to check and make certain the structure of the composite isn't compromised somehow. Basically, you're gambling. And if you ride that bike hard, you could be gambling pretty high stakes. In my mind, it simply isn't worth it when there are so many options for frames that cost so little.
 

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Discussion Starter · #10 ·
Thanks all. I am trying to get over the initial shock that I have a worthless frame after 6 months of riding especially since I was riding as the manufacturer intended. I suppose worse tragedies have happened in the last hour.

So, if I replace the frame, I will NOT be buying a Giant XTC Composite. I would be a fool to do so. Any recommedations on where to pick up a good carbon frame a good price?
 

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Drill a small hole at the end of the crack. It will continue to propagate if you don't. Find yourself someone who TIG welds. Look at some of his/her work. If it looks good then hire them to do the weld. Shouldn't be more than $100 (free if the guy is cool).

A nicely done TIG weld will be hardly noticeable and will be good as new (stronger actually). Repaint if you want. Don't worry about sleeving unless it gives you peace of mind.
DITTO. Drill small hole just under crack! This stops the crack fom traveling. Any machince shop should be able to weld it up for you. They will have to grind around that area so even if they don't do a perfect job you could grind it down smooth. The only problem is on the inside of the tube where the welds may protrude! I have a dremel wand that would fit right inside the tube easily. Tough to see what your working on but might be a solution.
 

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SS Pusher Man
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DITTO. Drill small hole just under crack! This stops the crack fom traveling. Any machince shop should be able to weld it up for you. They will have to grind around that area so even if they don't do a perfect job you could grind it down smooth. The only problem is on the inside of the tube where the welds may protrude! I have a dremel wand that would fit right inside the tube easily. Tough to see what your working on but might be a solution.
Drill a small hole at the end of the crack. It will continue to propagate if you don't. Find yourself someone who TIG welds. Look at some of his/her work. If it looks good then hire them to do the weld. Shouldn't be more than $100 (free if the guy is cool).

A nicely done TIG weld will be hardly noticeable and will be good as new (stronger actually). Repaint if you want. Don't worry about sleeving unless it gives you peace of mind.


Guess you didn't read where it was a carbon frame????
 
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