Hello Mustachians! Long time reader, first time poster. I have a question I think this group might have a good answer for. I normally use a U-lock for my bike, which came with a plastic mount that attaches to the bike frame. Picture:

The problem is that the weight of the lock is too much for the plastic mount, so after 3-4 months the mount cracks.

I have replaced two of them at ~$10 a pop including shipping, but I can't take the waste of money and plastic anymore. I'm looking into back rack options, but not sure my bike can accommodate one, so looking for alternatives. Any suggestions appreciated!