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Cracked paint or seatpost shaft?

Old 03-25-19, 03:14 PM
  #26  
phughes
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Originally Posted by RiceAWay
You made the mistake of misspelling "frame"



By the way - There seems to have been a remarkable reduction in breaking carbon frames. I don't know if people are finally getting the idea that you don't complain about a carbon fiber frame breaking when you run into the side of a car at 15 mph or if they are getting the hang of the material and we're getting very few frames and forks breaking without reasons? I have seen this occur but have finally gone back to CF and my Colnago CLX 3.0 is easily the best bike I've ever ridden. But perhaps it just fits me better than most other bikes?
Probably a combination of both.
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Old 03-25-19, 07:21 PM
  #27  
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New frame, that is great CS!
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Old 03-26-19, 11:54 AM
  #28  
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Originally Posted by RiceAWay
I made the mistake in thinking the frame was carbon since I saw so many carbon frames broken that way. You made the mistake of misspelling "frame" and Ribble agreed with my assessment that was a dangerous crack.

By the way - There seems to have been a remarkable reduction in breaking carbon frames. I don't know if people are finally getting the idea that you don't complain about a carbon fiber frame breaking when you run into the side of a car at 15 mph or if they are getting the hang of the material and we're getting very few frames and forks breaking without reasons? I have seen this occur but have finally gone back to CF and my Colnago CLX 3.0 is easily the best bike I've ever ridden. But perhaps it just fits me better than most other bikes?
My comment, "Probably a combination of both," was in regards to your comment on the reduction of broken frames.

As for the Colnago CLX 3.0 being the best bike you have ridden, I am sure fit has something to do with it, but nonetheless, it's a great bike. Sometimes it is hard to nail down exactly what what makes a bike feel right for us, but when you find it, it's great. Enjoy!
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Old 03-26-19, 12:16 PM
  #29  
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I worried when my nice carbon frame showed a pair of cracks similar to the 3 and 9 o'clock cracks in the photo, but shorter. I kept a photo to see if they were getting worse or not.

That was 9,000 miles ago. No change at all. Yeah!
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Old 03-26-19, 02:27 PM
  #30  
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Originally Posted by Hoopdriver
I wouldn't drill relief holes just yet, but instead just watch for a while. The big question is how the cracks happened. Assuming that the post is the correct diameter, perhaps something happened during initial assembly. If the seat post is too small, flexing could have done it as would over-clamping. It's certainly worth it to get out the calipers and measure. How do the cracks line up with the post clamp?
Originally Posted by RiceAWay
That is definitely cracking of the seat post probably from overtightening the seat post clamp. This is a dangerous condition and this is one of the few areas on a carbon bike that I would trust a repair. It you let this go it can crack around the circumference and the seat post could out on a hard bump in the least safe place.
Aluminum frame, carbon post.

I also wonder about perhaps a marginally compressible Carbon post being over-tightened.

On the bright side, someone posted a photo of this Tandem a while ago.

https://www.bikeforums.net/tandem-cy...ne-tandem.html



Steel, of course, but it looks like half the mast was cut off, either by an owner, or at the factory, and it is still stable.

if the post mast was to break (it would take a very long crack), it would result in a twisty post, rather than a sudden loss of the seat.
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Old 03-26-19, 02:55 PM
  #31  
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paint for sure
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Old 04-02-19, 03:47 PM
  #32  
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Originally Posted by CliffordK
Aluminum frame, carbon post.

I also wonder about perhaps a marginally compressible Carbon post being over-tightened.

On the bright side, someone posted a photo of this Tandem a while ago.

https://www.bikeforums.net/tandem-cy...ne-tandem.html



Steel, of course, but it looks like half the mast was cut off, either by an owner, or at the factory, and it is still stable.

if the post mast was to break (it would take a very long crack), it would result in a twisty post, rather than a sudden loss of the seat.
I've had a short seat post hop up high enough that when you were slammed down at the other end of the bump it levered the post over and broke it off. The riding home standing was not all that pleasant. Now I never use short posts like Colnago used to make
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