Not sure how? Could it work loose. I've never attempted to take cranks off.This is how self-extracting bolt looks like, maybe you lost the threaded ring part of the bolt (the left on photo)?
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Reinstalled it but it's exactly like the picture above without the bolt on the left. I did have a bike shop change the chainring about 1500kms ago. Maybe they fucked up and when reinstalling. No idea how but can't really go back there now after such a long time. I'll go to my Specialized dealer and see what they can do.Show me photo of your self extracting bolt on the drive side ...
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