compact or triple

radiation man
radiation man Posts: 446
edited September 2008 in Road beginners
im going to get a trek 1.7 at moment i have a triple on my bike 8 speed 52/42/30 and 12/25 rear cassette, to match this will a 105 compact with 50/34 on front and 11/27 on rear be about the same or do i need a bigger rear cassette if they make one

Comments

  • Smokin Joe
    Smokin Joe Posts: 2,706
    34*27 will give you a bottom gear of 34 inches, your present set up has one of 32.4. Your top gear with the compact will be 5 inches higher.

    I would not worry about a small difference like that, but only you will know whether it would suit you.
  • would a 28 rear cassette be same as now its just that i have needed to use a 30 front and 25 rear on some hills
  • Smokin Joe
    Smokin Joe Posts: 2,706
    A 28 sprocket will give you a bottom gear of 32.78 inches, so near to what you have now you won't even notice.
  • dennisn
    dennisn Posts: 10,601
    Smokin Joe wrote:
    A 28 sprocket will give you a bottom gear of 32.78 inches, so near to what you have now you won't even notice.

    But will a 105 rear mech take a 28 tooth cog? Maybe, maybe not. I do know that if you need a bit lower gearing that you can buy a 33 tooth front ring from TA Specialties.

    Dennis Noward
  • bahzob
    bahzob Posts: 2,195
    Why change from a triple to a compact?
    Martin S. Newbury RC
  • bahzob wrote:
    Why change from a triple to a compact?

    'Cos triples aren't cooooooool enough. Tch, don't you know anything :wink:
    'How can an opinion be bullsh1t?' High Fidelity
  • jezcc
    jezcc Posts: 111
    Cos triples aren't cooooooool enough. Tch, don't you know anything

    That is a fact, that's why I ride a compact. A triple is fine for a tourer if that's what you're into, but it simply looks uncool on a racer.
    FCN 4-6 depending

    2008 Rocky Mountain ETSX
    2008 Ribble
  • feel
    feel Posts: 800
    jezcc wrote:
    Cos triples aren't cooooooool enough. Tch, don't you know anything

    That is a fact, that's why I ride a compact. A triple is fine for a tourer if that's what you're into, but it simply looks uncool on a racer.

    It's a lot less cool when you have to get off and walk :lol:
    We are born with the dead:
    See, they return, and bring us with them.
  • jimwin
    jimwin Posts: 208
    <Quote> That is a fact, that's why I ride a compact. A triple is fine for a tourer if that's what you're into, but it simply looks uncool on a racer. <Unquote>

    Triples are not just about smaller gears (though they do help). They're also about keeping your cadence steady by reducing the change you get when moving between the front rings. Most times you'll only change between the big and middle rings. The granny is there for when you really need it. Plus you can also reduce wear by keeping a better chain line with a triple.

    Mostly the decision depends on where you ride. If your hills are not steep, then a double is fine. But once you hit 20% or more, a triple is well worth the extra few grammes.

    - JimW