I have a pair of Deda Pista 31.8mm bars (6061 aluminum) that have been indented on the rear of the clamp area by the stem. Where the edges of the stem contacted the bars, there is now a fairly significant depression. While I don't believe I over-torqued the faceplate during installation and subsequent re-installations, I guess it was enough to deform the aluminum of the handlebars.
Does anybody have bars that have indented in a similar manner, and if so do you still ride them? I understand that cracks, scratches and gouges become stress risers and that a bar can fail at those points, but the indentations shown below are very smooth, free of sharp edges or burrs. Does this type of deformation also represent a stress riser? Is the larger 31.8mm diameter clamp area less likely to fail because it is stiffer than a 26.0mm diameter clamp area? It is also my understanding that 6000 series aluminum is less brittle than 7000 series aluminum. Does this mean it can more readily accept this type of deformation?
Thanks in advance.