Shimano HT2 crank bolts

chriskempton Posts: 1,245
edited February 2010 in Workshop
I've just round out the allen key slot for about the 4th time on an HT2 LH crank pinch bolt, I try to tighten and loosen them very carefully, using a torque wrench with an allen key socket that's in A1 condition, and I brace the bit into the bolt to keep the interface as tight as possible...... but still it rounds out.

Anyone else have a similar problem? I tighten them to the recommended 15nM, but I'm thinking I should just do them less tight (by handheld allen key) in the future.

Your advice appreciated.......