I noticed fubar5 's crank is 4 arm and I have been wondering about mine. My mtn bike has 4 arm and after 18 months the middle chain ring has bent 3 times. At first I thought I had somehow banged it on a rock or log. Last week it got slightly bent and I am pretty sure I didn't bang it. I am pretty good about not cross chaining. It is STX shimano and the chainrings are aluminum.
Are chainrings on four arm cranks prone to bending?
Can I bend them just by hammering?
Can i bend them by changing gear underload ( well maybe it has happened once or twice) ?
Fatigue on the chainring?