Thanks, gents. Just to be clear, what am I doing damage to? Is it the cranks, the bottom bracket, or both? If the BB is involved, I actually have a brand-new spare that's been sitting in a drawer for two years, so that's luck. Either way, I'm dumping my cranks. The current ones are some leftover Shimano Nexus ellipticals that I don't really enjoy, anyway. I wonder if it would be unethical to resell the cranks on fleabay.