chain stay protection on carbon frames I am worrying about this type of protection against chain sucks. After 1-2 months with a new Cannondale F29 2, I've found out that this part was not where it should be. Instead, the chain did it's ugly job.

Talking to a mechanic, he guessed(!) that attaching metal to carbon might not always work, both materials have quite different properties, i.e. that loosing the protection should be a common problem. Is it?

Apart from myself, I've never heard of issues with lost chain suck protectors...


EDIT: Thank you for your comments, and sorry for not being able to reply earlier! 

@Criggie / @Frisbee: The following image shows a Cannondale F29 with a chain stay protector attached left of and next to the largest chainring..



@User 3875425: No, AFAIK, by reducing the space between largest chain ring and the frame, they should actually (also) prevent chain sucks. Here, I am very open for correction! BTW: Currently, I am using a can tin wrapped around the frame thighly around the correspunding postion. Looks weird, is not 100% fixed all the time, but works.

@Frisbee: There is a legal case going on.

@ebrohman: The question is whether you have or have heard of problems with metall chain stay protection as weak design part on carbon frames. In order to do so, you should either have such expereience made yourself or you should be in a position, as bike dealer, club member, where you can notice such issues - or not.

---END EDIT
My experience is that they help minimise the damage.


By being malleable and typically having a foamy backing (for shock). Usually only good for a few impacts. 
By having ~1mm foam and being somewhat rigid it may help with less aggressive sucks. 
But if they were stiff and had no tolerance toward the frame, it would mean all the force would transfer through and damage the frame at the edge of the protector. 


Chain suck typically has a range of causes and is very noticeable and should be addressed straight away.

I wouldn't see it as a weak design part, more in line with something like a crumple zone of a car that is meant to give way, if that makes sense.