Broken rear dropout

robbohenn

Had a bad day yesterday on my first outing for months. First an exploding inner tube when going over a large stone and then my rear dérailleur broke 3 miles from home. Once I'd got back a closer inspection revealed a broken spoke, a broken chain and a broken rear dérailleur with half of the rear dropout still attached! The bike is well maintained, 3 years old and only done about 1200 miles. Would I possibly have a warranty claim and if not, is it repairable?
Thanks.

keezx

Rear derailleur is probably only the hanger that broke, which is replaceble.
Chains and spokes can be replaced too...

woolwich

Unfortunately I would be surprised if you have a warranty claim after 3 years.
Hopefully Keez is correct and the hanger will be replaceable. They are designed to break if they get hit or damaged rather than damage the frame. You simply screw a new hanger on. Available online from specialist places or your good old bike shop/ Halfords etc.
The wheel may or may not be worth saving depending how much of a mangling the derailleur gave it. Could be just a spoke, could be replacement.
The mech has probably had a really good twisting. I have never had a lot of luck with repair or straightening when they have been thrown into a wheel. Probably easiest to replace.

robbohenn

Thanks for your advice. A more thorough check this evening revealed a broken dropout (hanger), so I will take the parts to where I bought it and get a new one. Maybe the right time to change to twin chainring as on triple at the moment.

keef66

Best get your terminology right then

The dropout is the bit of the frame the axle sits in.
The hanger is the bit the rear derailleur screws into.
On alu and carbon frames the hanger is usually a separate, sacrificial alloy part screwed onto the frame, and designed to fail in order to avoid damage to the frame itself.
On steel frames the hanger is usually an integral part of the frame, and tends to bend rather than break.

(Occasionally the replaceable hanger design means it also forms part of the dropout, but generally they are two different things)

dgunthor

were you in the easiest gear at the back when this happened? if so, might be that the rear mech wasn't adjusted correctly and allowed it to go into the spokes? (happens quite a lot)

robbohenn

You're right Keef, it was the hanger that broke.
dgunthor, I wasn't in lowest gear on cassette as I try to hardly ever use it, but I must say that whilst I was out it occasionally felt like an "automatic" as the chain did move between a couple of cogs without any help from me!