Hi,

landotter wrote:
On Nov 14, 6:58 pm, Death From Above
wrote:
I have a mongoose mountain bike with 3 gears in the front and 7 in the
back. The rear derailleur is all bent up and needs to be replaced.

Something like a $20 Shimano Altus will do you just fine. Just use
your search engine for the best deal.

If you use your bike a lot I wouldn't go for a Shimano A* (Altus,
Alivio,...) because you may or may not be lucky ;-) I used one of the
"Deore" groups RD and got *much* better performance out of it - as well
in shifting accuracy as in little running resistance. Actually I only
had two A* and one Deore LX and I'll never again want an A* ;-)

Please, before you mount your new RD, check the alignment of the
derailleur hanger - if it's bent you'll never be able to adjust your
derailleur correctly...

Good luck...