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Removing 2015 Campagnolo rear derailleur from hanger

kayodotkayodot Posts: 143
edited December 2016 in Workshop
I've had a look on here and other forums, but can't seem to find a conclusive answer.

What is the correct method for removing a Campagnolo RD (chorus, record or SR) from a RD hanger? I previously tried to do this using a T25 torx key from the drive side, and somehow ended up either rounding out the bolt or shearing it in two (the mounting bolt now spins freely when I turn the T25, but the RD remains attached to the hanger). Luckily my hanger is removable, so I just took it off, popped a new one on and also had a spare RD knocking around (long story).

On the off chance I need to remove it in future, how should this be done? Consensus seems to be that these require some elbow grease. Some info suggests using a T30 from the NDS - there is a hex recess on the mounting bolt that is too large for my T25 key, none of my hex keys fit and I don't want to buy a T30 key only to find it a) doesn't fit or b) breaks another mounting bolt when I really give it some welly.

Cheers in advance.


  • flasherflasher Posts: 1,731
    Depends on the age of the mech, most now use Torx T25. and undo from the drive side. ... _groupsets
  • kayodotkayodot Posts: 143
    It's a 2015 mech, as per title.

    Are you sure? I'm a little suspicious, just because of the issue I described in the original post, with it requiring quite a lot of force to undo (I must note I have done it successfully once before), although I don't want to risk killing another RD and hanger through trying...
  • lesfirthlesfirth Posts: 1,206
    :) Well Flasher,you know that you can take a horse to water,but you can not make it drink. At least you tried.
  • kayodotkayodot Posts: 143
    Thanks for the condescending snide reply Les, appreciated.

    The supporting material posted details installation - is it necessarily the case that the reverse is applicable for removal? I don't intend my questions to come across as ignorant or ungrateful, it's just that I have tried that method, and the force required and the damage caused (on one occasion), makes me question whether there is a more correct method?
  • cougiecougie Posts: 22,512
    Have these gone torx too? I've only ever had allen key bolts on mine.

    I know the bolt is recessed but can't you see what it looks like with a torch or phone cam?

    You simply unscrew the bolt. It shouldnt be a huge amount of force needed.
  • kayodotkayodot Posts: 143
    I think there may be some confusion. The drive side of the bolt is recessed, and it's a T25 (I did install the RD this way, as per the above videos). I have tried undoing the RD using this side of the bolt - it requires a hell of a lot of force - it worked once before, but when tried a second time at a later stage, the bolt either snapped in its middle, or rounded out (it doesn't look like it has rounded).

    On the NDS of the same mounting bolt, there is a recess shaped for a hex key. None of my hexs fit it, but I am wondering whether this side should be used to remove the mech (similar to as detailed in this thread viewtopic.php?t=12914193)

    edit: page 18 of this ... part_A.pdf at least tells me what spare parts I'll need to salvage derailleur #1
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