I took off from a stop light yesterday and decided to really crank on the pedals, see how long I could keep up with traffic. I push down hard with my right foot and !BAM! the chain falls off to the outside of the big chainring. I stop put the chain back on and try again, same result. I stop in a nearby parking lot and try it again while watching. When my foot hits about 3 o'clock the chain bends around the teeth at the top and derails to the outside. Further investigation reveals both rings move 3-4mm to the outside at this position. Took the rings off and it seems that the spider is bent. I know for a fact it was straight when I put it on. Brand new drivetrain, only about 80miles on crank (FSA Energy compact), bb (FSA), chain (Ultegra 9), cassette (ultegra 9) and both derailleurs (ultegra 9), Less than 6 months old
Has anyone ever bent a crank spider sprinting to speed?
I took off from a stop light yesterday and decided to really crank on the pedals, see how long I could keep up with traffic. I push down hard with my right foot and !BAM! the chain falls off to the outside of the big chainring. I stop put the chain back on and try again, same result. I stop in a nearby parking lot and try it again while watching. When my foot hits about 3 o'clock the chain bends around the teeth at the top and derails to the outside. Further investigation reveals both rings move 3-4mm to the outside at this position. Took the rings off and it seems that the spider is bent. I know for a fact it was straight when I put it on. Brand new drivetrain, only about 80miles on crank (FSA Energy compact), bb (FSA), chain (Ultegra 9), cassette (ultegra 9) and both derailleurs (ultegra 9), Less than 6 months old
Has anyone ever bent a crank spider sprinting to speed?
