Rear derailleur snapped off...

Moominman2 Posts: 389
edited June 2014 in Workshop
So I forgot to close my saddle bag and an innertube manages to pull my rear derailleur off.

It's a shimano 105. Is it as simple as buying another shimano 105 to replace it? Or are there different types? I'll probably buy second hand off eBay.

Novice question !



  • simonj
    simonj Posts: 346
    Has it bent/snapped the rear hanger or the actual derailleur? I've seen the hanger break before (by design) as it's only £10 to replace then as your derailleur stand a good chance of being intact.
  • simonj
    simonj Posts: 346
    This bit :-

  • Moominman2
    Moominman2 Posts: 389
    Thanks for the response.

    It's the actual derailleur. The hanger looks ok.
  • simonj
    simonj Posts: 346
    Blimey, I'm surprised you did not damage the hanger as they are normally made to be the weakest bit so that they go first. Just buy a new hanger, make sure same speed obviously and cage is same length so you don;t need to change chain. I'd check the hanger again, mine looked ok, but was actually slightly bent which made indexing trickier.
  • Moominman2
    Moominman2 Posts: 389
    Probably a good idea! I'll take it off later and have a look. Stupid mistake...was so gutted !

    Would you trust one used of eBay for a tenner? And how difficult is it to set up without going to a lbs?

    Thanks for your help
  • ic.
    ic. Posts: 769
    A 105 rear mech is about £28 brand new, I'd go with that.

    It's a very simple job to screw on and then attach cables, run the chain through and index the gears, but there are plenty of videos on youtube too.
    2020 Reilly Spectre - raw titanium
    2020 Merida Reacto Disc Ltd - black on black
    2015 CAAD8 105 - very green - stripped to turbo bike
    2018 Planet X Exocet 2 - grey

    The departed:

    2017 Cervelo R3 DI2 - sold
    Boardman CX Team - sold
    Cannondale Synapse - broken
    Cube Streamer - stolen
    Boardman Road Comp - stolen
  • Matthewfalle
    Matthewfalle Posts: 17,380
    Go for new that way you know it's not jazzed, which is why most things end up on the Bay........

    Don't forget to set fire to the old one.
    Postby team47b » Sun Jun 28, 2015 11:53 am

    De Sisti wrote:
    This is one of the silliest threads I've come across. :lol:

    Recognition at last Matthew, well done!, a justified honour :D
    smithy21 wrote:

    He's right you know.
  • Moominman2
    Moominman2 Posts: 389
    Thanks everyone for your help.

    I'll go buy one now !