Helicoil Crank Arms?

[SummitFever]

... my guess would be to avoid any thin wall applications and/or high stiffness layups, which cranks I would classify as.

All of the carbon cranks I have seen have an aluminium insert that has the pedal threads. I am not aware of any carbon cranks where the thread is into actual carbon fibre. The insert typically has a longer shank that runs along the inside of the hollow carbon crank arm towards the crank axle. Some designs are almost like heavily machined alu cranks with a carbon wrap for strength and rigidity.

 

[Calvin27]

All of the carbon cranks I have seen have an aluminium insert that has the pedal threads. I am not aware of any carbon cranks where the thread is into actual carbon fibre.

Lol no morning coffee and I read the post as 'the insert fell out so I'm going to helicoil the carbon!'