Forum home› Commuter cycling forum› The workshop

Compact to triple

skins2skins2 Posts: 78
edited January 2010 in The workshop
OK, I've just added 25kg to my bike weight in the form of a child + trailer and some of the hills are now proving cardiac-arrest inducing.

I have a Focus Mares Disc 09 (spec here) and would like to replace the Gossamer with this Shimano 105 triple. I just need to know if I need to buy anything else to complete the transformation.

Thanks in advance.

Posts

  • cjcpcjcp Posts: 13,345
    Check whether you need to get a triple-compliant front mech.
    FCN 2-4.

    "What happens when the hammer goes down, kids?"
    "It stays down, Daddy."
    "Exactly."
  • skins2skins2 Posts: 78
    Like this?

    I think I probably do as mine just says Shimano 105 as opposed to Shimano 105 triple. How do I check?

    They aren't that expensive so it's not a deal breaker if I do need one, but I'd really like to know if my shifters are compatible as replacing them would be out of the question.
  • cjcpcjcp Posts: 13,345
    Yup. Your existing front mech has a max tooth range of 16T, you'll need a triple because that has a range of 20T, which the new 105 chainset will have.

    Check whether you need a braze-on or band mech.
    FCN 2-4.

    "What happens when the hammer goes down, kids?"
    "It stays down, Daddy."
    "Exactly."
  • skins2skins2 Posts: 78
    OK, thanks.

    I've just seen theseshifters which could suggest I need a new LH triple shifter. But in the description it says compatible with dual and triple chainsets.

    Can anyone clarify if I need a new LH shifter for a triple chainset?
  • cjcpcjcp Posts: 13,345
    Never sure about gear inches and stuff, but how would you get on with a cassette which offered easier gearing e.g something with a 27? Would be a lot cheaper.
    FCN 2-4.

    "What happens when the hammer goes down, kids?"
    "It stays down, Daddy."
    "Exactly."
  • skins2skins2 Posts: 78
    Unfortunately it came with a 12-27. It is mainly flat around here but there are a few nightmare hills.
  • CarlosDSanchezCarlosDSanchez Posts: 455
    You will need a triple LH shifter. Check that the one fitted isn't a triple though as it would be compatible with double chainrings, the limit screws would just prevent you using the third "click"

    As the bike was supplied with double chainrings I'd of thought the shifter would only be a double as they're cheaper.
    Dolan Preffisio
    2010 Cube Agree SL
Sign In or Register to comment.