Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

New Rear Mech, 9 speed.

Options
  • 14-08-2016 3:34pm
    #1
    Planet X
    Moderators, Recreation & Hobbies Moderators Posts: 3,976 Mod ✭✭✭✭


    In the market for a new above.
    Looking at SRAM X5, Deore M591 etc.
    9 speed, 11-32, Audax bike.
    Any other recommendations? Shimano.
    Cheers.


Comments

  • Options
    #2
    smacl
    Moderators, Society & Culture Moderators Posts: 15,754 Mod ✭✭✭✭smacl


    What's up front, AFAIK derailleur capacity is based on maximum tooth difference between front and rear, so if its a triple up front and you're running 11/32 back you need a lot of capacity (e.g. Deore). Compact up front, and AFAIK any medium cage will work.


  • Options
    #3
    Planet X
    Moderators, Recreation & Hobbies Moderators Posts: 3,976 Mod ✭✭✭✭Planet X


    Yeah.....triple.

    Must check tooth diff then.


  • Options
    #4
    Planet X
    Moderators, Recreation & Hobbies Moderators Posts: 3,976 Mod ✭✭✭✭Planet X


    So.......it's the difference in teeth between the front chainrings, 48-38-28 which is 20,
    and
    the difference between the smallest rear cog (11) and largest (32) which is 21..........combined.
    41.

    This correct?


  • Options
    #5
    Planet X
    Moderators, Recreation & Hobbies Moderators Posts: 3,976 Mod ✭✭✭✭Planet X


    For eg then,

    SRAM X7, long cage has a 45 tooth capacity, which seems to fit the bill.
    The medium cage of above has a 37 tooth capacity which is out.
    Correct?


  • Options
    #6
    smacl
    Moderators, Society & Culture Moderators Posts: 15,754 Mod ✭✭✭✭smacl


    Planet X wrote: »
    For eg then,

    SRAM X7, long cage has a 45 tooth capacity, which seems to fit the bill.
    The medium cage of above has a 37 tooth capacity which is out.
    Correct?

    Looks right, see related question here; http://bicycles.stackexchange.com/questions/7264/how-to-calculate-the-capacity-of-a-rear-derailleur. Road triple I have is campag / FSA mix 52/39/30 front, 30/13 rear, long cage Veloce DR, which works well enough.


  • Advertisement
  • Options
    #7
    Eamonnator
    Registered Users Posts: 6,561 ✭✭✭Eamonnator


    Ensure that your shifters are compatible with Sram X7.
    ASAIK some of those Sram rear mechs pull a different length of cable than Shimano ones


  • Options
    #8
    CramCycle
    Moderators, Sports Moderators Posts: 24,948 Mod ✭✭✭✭CramCycle


    As Eamonnator says, what shifters are you using at the moment?


  • Options
    #9
    Alek
    Registered Users Posts: 4,520 ✭✭✭Alek


    triple up front and you're running 11/32

    I'm running 30/40/50 triple and 11-34 with the longer Sora road derailleur (3500) and no problems...


  • Options
    #10
    Planet X
    Moderators, Recreation & Hobbies Moderators Posts: 3,976 Mod ✭✭✭✭Planet X


    CramCycle wrote: »
    As Eamonnator says, what shifters are you using at the moment?

    Eh........cheapo Sora I think. Came with bike.
    But, most likely I'll be switching to Down Tube shifters on this bike aswell. DA down tube shifters.

    I'll probably plumb for XT long cage M771 (I think it is?)


  • Options
    #11
    paul a newman
    Registered Users Posts: 559 ✭✭✭paul a newman


    i have a boxed XTR rear mech if you're interested, never used, for E50. Cost a lot more when I bought it new 8 yrs ago


  • Advertisement
  • Options
    #12
    Eamonnator
    Registered Users Posts: 6,561 ✭✭✭Eamonnator


    Dura Ace 9 speed down tube shifters will work fine with an XT long cage M771 rear mech


  • Options
    #13
    Planet X
    Moderators, Recreation & Hobbies Moderators Posts: 3,976 Mod ✭✭✭✭Planet X


    paul a newman wrote: »
    i have a boxed XTR rear mech if you're interested, never used, for E50. Cost a lot more when I bought it new 8 yrs ago

    What???? Is it 8 years old then???


  • Options
    #14
    Eamonnator
    Registered Users Posts: 6,561 ✭✭✭Eamonnator


    Planet X wrote: »
    What???? Is it 8 years old then???

    Recognise a bargain, when you see it.


  • Options
    #15
    Planet X
    Moderators, Recreation & Hobbies Moderators Posts: 3,976 Mod ✭✭✭✭Planet X


    paul a newman wrote: »
    i have a boxed XTR rear mech if you're interested, never used, for E50. Cost a lot more when I bought it new 8 yrs ago

    Any pics. or links then Paul?


  • Options
    #16
    paul a newman
    Registered Users Posts: 559 ✭✭✭paul a newman


    its in a box in the shed, prob dig it out tomorrow, originally bought it for audax build up with dura ace bar end shifters, but went with an Ultegra set up instead, like I say, It's been in its box for a while now but never been used, will post pics tomorrow


  • Options
    #17
    paul a newman
    Registered Users Posts: 559 ✭✭✭paul a newman


    model rd-m900, max cog 32T, its for 8 speed, but I think it works with 9 speed.
    i have it boxed, but it has been used, if you're still interested, I'll stick some pictures up later
    molkp1tdl


Advertisement