Carbon Fiber Canyon MTB - Cracks...??

[marcus_ec]

Marcus Sweden.

I have to ask the German community. How many people have problems with cracks in your Canyon carbon frames?

I am on my second Grand Canyon CF SLX 29 frame with a crack at the seat clamp? twice in 4 months ... Starting to get really tired of it!

My club mate have destroyed 6 Grand Canyon CF 26 with cracks in different places.

Myself have run down two carbon frames by 26 inches (crack) ...

Are there more in germany with problems? thinking primarily 29er

My Chinese carbon frame is better, you have to have 2 bikes when you ride Canyon...

 

[axisofjustice]

http://www.mtb-news.de/forum/showthread.php?t=651179

A common occurance especially with the color scheme "slate".
You might wanna use google translate to get an overview. Canyon theoretically does repair the frames on request, but claims cracks are a normal signs of usage.

 

[filiale]

I believe that Marcus meant -> cracks = "Risse" as he talked about "frames destroyed". The other thread points out only flaking/spalling/chipping.

Marcus, can you please post some pictures of your frame and the one of your friends to make sure we are talking about the same thing ? Thank you

The carbon frames are currently an important topic in this community.

 

[marcus_ec]

Yeah I mean cracks (broken) frames. My first frame i used 1,5 months, my second frame (warranty) maximum 10 rides. And i have 2 MTB this is my racebike...

My first frame (warranty)

My second crack 10 rides. Have not contacted Canyon yet... Will finish my season first. So boring!!

 

[Drahtesel_]

I would contact canyon...

Imagine you will fall or just something else which will follow to a "real broken" frame.
Canyon will threat it probably as an crash caused by yourself and I'm not sure if you will get a new one on warranty so easily.

 

[marcus_ec]

Warranty is not at problem, but im just querios if im alone of this problem? Canyon is very popular brand i in Germany.

 

[Drahtesel_]

Maybe change the thread title to "Risse am Grand Canyon CF" or add the word "Risse" after "Cracks" to attract more attention.

Which frame size do you ride?
Did you overstress the bike somehow?

As you said, Canyon is popular here in germany. If this is not an single case I'm sure someone before you would express his disaffection.

 

[marcus_ec]

Hello medium with 86cm legs and 1.81cm height, im between medium and large, but Canyon recommend medium because i have short arms. My seatpost its not at maximum.

Risse in place

 

[biketiger2]

Marcus, it is the result of this problem:

http://www.mtb-news.de/forum/showthread.php?t=621468&highlight=spiel+sattelst%FCtze

 

[marcus_ec]

biketiger2: Great! Im not alone... but is very intresting with my new frame i also got a Risse. Starting to get realy tired at this!

 

[Deleted 48245]

@Marcus ec: You wrote your seatpost is not at maximum.
Could you make a picture where we can recognize how deeply you have put the seatpost into the frame? We would like to see the complete seatpost with the saddle.

 

[marcus_ec]

I have a KCNC 30.9mm - 400mm with the same measurements like the original seatpost.

This have both me and Canyon sweden measuring very accurately.

Picture bike: http://instagram.com/p/cMBgR_hWs5/#

 

[Deleted 48245]

It looks very critical. What´s your weight? In my opinion the frame is overstressed.

 

[marcus_ec]

74kg

 

[Deleted 48245]

Hm, my weight is 64kg and my seatpost looks like yours ( I have a 26" bike but the situation is similar ). I have no problems.

10 kg more and your legs are longer. It may be that this difference is responsible for the cracks. It is borderline.

 

[marcus_ec]

But yours is a 26

 

[Deleted 48245]

Yes I know but the physics is equal. I believe the long seatpost combined with the weight is responsible for the cracks. The forces should not be underestimated.

 

[marcus_ec]

Before i was buying medium i was talking to Canyon about the framesize. Medium is just find...

 

[Deleted 48245]

Yes I know but it helps you not at the moment. You have a frame with cracks and I try to explain where the problem might lie.

 

[biketiger2]

biketiger2: Great! Im not alone... but is very intresting with my new frame i also got a Risse. Starting to get realy tired at this!

Your Risse is only the final result of the moving seatpost in your lower seattube. At the clamp it seems to be tight but the forces are so high at this small area that as the result the tube cracks. May be all of the frames due to summer does have this problem.
Hope the 2014er frames will be better.

 

[Twenty9er]

One possibility is a too high tightening torque on the seat clamp. Carbon doesn't like high pressure forces.

 

[Deleted 48245]

One possibility is a too high tightening torque on the seat clamp. Carbon doesn't like high pressure forces.

For his first frame ( first picturce ) you´re right but he received a new one ( warranty ).

For the second crack the clamp should not be responsible.

 

[marcus_ec]

6nm torque at the Clamp.

 

[dj_holgie]

6nm torque at the Clamp.

Thats too much. I only need below 2 NM with friction paste for carbon. Do you use friction paste? I would highly recommend it for carbon seatposts.

 

[filiale]

6NM is a lot...try it with less. If it does not hold it, use the right grease.