Rear Mech compatability?

BMKN
BMKN Posts: 222
edited April 2014 in Workshop
I need a new rear mech, I am running ultegra 53/39 chainset with rear cassette 11/25? I need to know the difference in short and medium cages, I am looking at 105 rear mech. My last one snapped on me with that not many mileage on her.
Will this be compatible

Top Features of the Shimano 105 5700 10 Speed Rear Derailleur
10-speed 105 wide link rear derailleur medium cage - GS
Advanced Wide Link design increases rigidity and shifting performance
Super stiff for fast and accurate changes across the cassette
Large 11 tooth pulleys increase service life and reduce noise
Super light shift action
Compatible with 8, 9, and 10-speed drivetrains
Maximum low sprocket 32T with double chainset
Maximum front difference 22T, total capacity 40T
Average weight 232 grams [/b][/b][/b]

Comments

  • ic.
    ic. Posts: 769
    Yes
    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
  • arlowood
    arlowood Posts: 2,561
    The one you list (medium cage GS) will be compatible but with your set-up you should be using the short cage (SS) rear mech.

    The GS is really only needed to accommodate the extra scope/chain tension needed when running a triple chainset.
  • BMKN
    BMKN Posts: 222
    The GS is really only needed to accommodate the extra scope/chain tension needed when running a triple chainset.[/quote]

    Clears things up a little bit. I seem to be very unlucky with rear mechs, my second one since the summer time
  • richiebones
    richiebones Posts: 379
    have you had the mech hanger alignment checked?
  • southdownswolf
    southdownswolf Posts: 1,525
    have you had the mech hanger alignment checked?

    More to the point, is this the same bike where the rear hanger has snapped off?
  • arlowood wrote:
    The one you list (medium cage GS) will be compatible but with your set-up you should be using the short cage (SS) rear mech.

    The GS is really only needed to accommodate the extra scope/chain tension needed when running a triple chainset.


    Or a larger cassette such as a 11-32.