compact frame sizes help?

lcowner
lcowner Posts: 341
edited July 2013 in Road buying advice
can someone claify this for me ,im looking to buy a used 56cm compact frame(trek alpha 1.5)
dimensions:
55.7cm virtual top tube.
Seat tube is 53.5 C-T (deceptive as it's a compact frame).
Frame stack is 57.6(what is this?)

i ride a 56cm standard ribble frame at present but its just the compact sizing seems to be very small to me :?:
my question is whether it will be ok for me??im 5'10 height,i cant try it for size as i will be getting it posted to me
thanks

Comments

  • imposter2.0
    imposter2.0 Posts: 12,028
    Frame stack is sometimes described as the vertical distance between the centre of BB to top of head tube - not a particularly useful measurement, imo.

    The measurements you've given don't sound particularly compact.
  • lcowner
    lcowner Posts: 341
    thanks for reply,well in comparison to my std frame,to me it measures up v small(maybe just me)..... :?
  • imposter2.0
    imposter2.0 Posts: 12,028
    lcowner wrote:
    thanks for reply,well in comparison to my std frame,to me it measures up v small(maybe just me)..... :?

    What's the top tube measurement of your Ribble? Look for a frame that matches that. The seat tube size is usually irrelevant, mainly because the seat pin can be adjusted to suit.
  • skyd0g
    skyd0g Posts: 2,540
    The most relevant dimension to check is the Virtual Top-Tube (a horizontal line from the centre of your seat tube to the centre of the stem) - see how this compares to your Ribble.
    Cycling weakly
  • lcowner
    lcowner Posts: 341
    with a tape it measures my ribble is approx 57.5,so i guess that answers my question then ........ :(
  • skyd0g
    skyd0g Posts: 2,540
    Depending on your physique / the Treks geometry, the VTT may not totally rule the Trek out. Many of the pro's ride a smaller bike, but use a longer stem (ie. 120 or 130mm) to 'fit' the bike.

    It's easier to get a bike that's 'too small' to fit you - longer stem, raised seatpost, set-back saddle etc. than to fit a bike that's too big for you. If the Treks a bargain & the rest of the geometry isn't too far off, it may still be worth a punt.
    Cycling weakly
  • kentphil
    kentphil Posts: 479
    I thought the Compact Trek frames referred to the compact chainset, as opposed to a triple chainset? Perhaps I'm wrong?
    1998 Kona Cindercone in singlespeed commute spec
    2013 Cannondale Caadx 1x10
    2004 Giant TCR
  • Grill
    Grill Posts: 5,610
    You'll need that Trek in a 54. You may be able to get away with a 56, but it won't be as comfortable or adaptable.
    English Cycles V3 | Cervelo P5 | Cervelo T4 | Trek Domane Koppenberg