Rear Derailleur snapped off

[duko]

Hello,
Today my rear derailleur has got caucht up on the spokes of my back wheel and snapped clean off on the way down a rocky hill.
I'm wondering if I need an apaptor for my bike for a new derailleur as one of my mates told me I'd need one?? My bike is a Specialized Hardrock Pro and the derailleur is Shimano Alivio.
Also what would be a good upgrade from this derailleur?
Hope someone can help,

[MTBLeague]

It may just be the part that is called the derailleur hanger that is bust, they are designed to do that saves the frame or the rear mech getting trashed, this part only costs around £15 and almost all recent Spech frames use the same one. So ask your local dealer they may have one in stock.

The trick is not to have the derailleur too near the spokes as any slop and side ways movement will cause this I did it several years ago, mangled the mech and spokes, it was like someone had just pulled the back brake on, nope it wasn't me, aww look what I done.

Best check the wheel for wobble and bent spokes.

[Sir_Queuesalot]

ditto above but be sure to get the exact hanger for your bike, there's hundreds to choose from, so speak to your dealer or friendly mechanic.

A decent upgrade from Alivio would be Deore LX or an SLX Shadow would be ideal if you're feeling a bit flush.

[duko]

cheers guys,
Yeah I think it sonds like the hanger, it's the part that fits directly onto the frame that's snapped. I've also bent the derailleur so that needs to be changed. I usually keep an eye on its position but i'd just blasted up a massive hill and was a bit to eager to come down, live and learn tho eh!

[tom83]

The new 2010 Deore rear mech is supposed to be damn good.

[allmountainventure]

Sounds like your limit screws might have needed adjusting. They stop the DR from moving to far over.

Or the DR or hanger was already bent and this caused it.

[Tango]

speak to your friendly mechanic.

A rare commodity, but i know a nice one in cheshire

[duko]

Just ordered the SLX Shadow which looks like the right tool for the job. I think my old derailleur had taken a bit too much abuse anyway, the links seemed to have quite a bit of play (side to side) which probably caused the misshap.