I was two miles into a ride when my rear derailleur exploded. I was just starting to mash on the pedal to get over some uphill roots when it happened. Is this the result of bad riding or care on my part or does it just happen sometimes?
I’ve never had this happen before even when I was a much worse, newer rider. This derailleur has just over 200 miles on it.
by deepstatedemon
13 Comments
Gahh damn. You were just pedaling? You got too much power in those thighs bro
I’ve only had that happen when I put too much force into a pedal stroke before finishing a shift. Could be other causes.
It likely hit something. You don’t always notice it, I’ve had it happen too where suddenly out of nowhere with seemingly no impacts it breaks. Sucks, but it’s part of the sport
Going off the condition of the chain, I’d say your der may have been out of tune a bit and you never completely got through the last shift until you gave er the beans
That chain is rusted, probably bone dry, so it already had a ton of friction. Im guessing the rider shifted several gears quickly and the chain couldn’t keep up. Wrapped up the derailleur.
How’d you get the beans above the frank?
Had something similar happen, one of the plates on my chain came loose, hooked the deraileur and smashed it in the seatstay, completely shearing off the hanger, luckily the deraileur was actually fine. Judging by the condition of your chain this might be the same case.
Bro, your chain is rusty, chances are you neglected that bad boy
Exact same thing happened to me on Friday. I think I must have clipped a rock or a root on a decent, as soon as I started pedaling after the decent it exploded. It looks exactly like yours. I replaced it yesterday and also found that the derailleur hanger needed to be replaced.
Shimano derailleur are usually pretty good with proper maintenance. I run a deore derailleur with an xt shifter and its been good for a few seasons now. Usually derailleurs just crap out from accidents or poor maintenance. Some cheaper sram derailleurs like the sx can get really loose over time tho.
Schroedinger’s rear derailleur is a famous physics problem where upon placing a rear derailleur into a closed box you never know whether it has spontaneously exploded or not.
Or you kicked up a small branch into it…
I will get downvoted I’m sure, but your chain is not rusted enough for this. Only three things can rip a mech apart like this. Catching a spoke, a chain link splitting or opening, or picking up a foreign object and having it pulled through whilst pedaling. If you were in a low gear (big cog) I would always blame catching a spike, but if you were in this gear when it happened, I would bet money it was either of the latter. You probably do need to look after your chain better, but if you look over the chain and there are no broken links or spread joints, then you probably picked up a stick or something
Looks to me a link ‘locked’ Midway of the derailleur cage. And the pedaling Force squeezed the cage off