Need fitting advice

Discussion in 'Cycling Equipment' started by Kjell Arne Olse, Jan 25, 2004.

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  1. After more than ten years of mountainbiking (and lurking on r.b.t for the better part of those ten
    years) I hit the road two years ago, first with a '96 Klein Quantum II (53 cm c-t), and the last
    year a '00 Cannondale Cyclocross (52 cm c-t).

    I opted for a cyclocross because I wanted to try and see if I could use the same bike for road
    racing (masters fattie, I'm afraid...) and this country's top MTB event, Birkebeinerrittet (11000
    participants). But as I don't seem to gain anything on the fire roads with a cross frame over my
    Klein Adroit Race, I will go back to a pure road frame for the coming season.

    The cyclocross frame does not offer any standover clearance either, and after the first hour of
    riding the lower part of my back start to ache. Not a serious pain, but more of being comfortable.

    As I usually prefer to buy used bikes I hope to get some fitting advice in this group. I have tried
    many of the web-based fitting calculators and they agree that with my 31 inch (78.5 cm) inseam I
    need a 51 cm c-c frame. But for the top tube I get values of everything from 52 to 56-57 cm. I'm
    5'8" tall (171.5 cm), so I have short legs and a relatively long torso. Body height measured from
    the floor to the base of the sternal notch is 54.5" (138.5 cm).

    Are my back aches a fitting-related issue or more of a muscle strength/flexibility issue?

    Can I use a standard frame, or do I have to get a custom fitted frame? I can get a good deal on a 52
    cm CAAD7 with complete Dura-Ace, so I hope this will do it, but maybe I need a longer top tube. Will
    a Trek be an alternative, or is there other options?

    Many thanks for your patience if you've read so far!

    Kjell Arne in icy Norway

    --
    http://www.brumunddal-sk.idrett.no/ Remove your clothes if you want to answer by e-mail! favorite
    fruit. (Sheldon Brown, http://harriscyclery.com/
     
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  2. "Kjell Arne Olsen" wrote:
    > As I usually prefer to buy used bikes I hope to get some fitting advice in this group. I have
    > tried many of the web-based fitting calculators and they agree that with my 31 inch (78.5 cm)
    > inseam I need a 51 cm c-c frame. But for the top tube I get values of everything from 52 to 56-57
    > cm. I'm 5'8" tall (171.5 cm), so I have short legs and a relatively long torso. Body height
    > measured from the floor to the base of the sternal notch is 54.5" (138.5 cm).

    Impossible to give specific fit advice on the net. There is more to fit than just body measurements.
    Need to see you on a bike and know your goals and preferences.

    > Are my back aches a fitting-related issue or more of a muscle strength/flexibility issue?

    Could be either or both. Or just not enough miles.

    > Can I use a standard frame, or do I have to get a custom fitted frame? I can get a good deal on a
    > 52 cm CAAD7 with complete Dura-Ace, so I hope this will do it, but maybe I need a longer top tube.
    > Will a Trek be an alternative, or is there other options?

    I really believe most people can get a good fit on a stock frame if they search long enough. Your
    height isn't unusual, and your long torso should be well suited to modern "stretched out" frames.

    You need to find a shop that knows how to do a fitting, and is willing to listen to you. Not one
    that just takes measurements and uses formulas.

    See: http://www.sbraweb.org/setup.htm

    Hope you find a bike that works for you.

    Art Harris
     
  3. "Arthur Harris" <[email protected]> wrote:

    >"Kjell Arne Olsen" wrote:
    >> As I usually prefer to buy used bikes I hope to get some fitting advice in this group. I have
    >> tried many of the web-based fitting calculators and they agree that with my 31 inch (78.5 cm)
    >> inseam I need a 51 cm c-c frame. But for the top tube I get values of everything from 52 to 56-57
    >> cm. I'm 5'8" tall (171.5 cm), so I have short legs and a relatively long torso. Body height
    >> measured from the floor to the base of the sternal notch is 54.5" (138.5 cm).
    >
    >Impossible to give specific fit advice on the net. There is more to fit than just body
    >measurements. Need to see you on a bike and know your goals and preferences.

    I know, but...

    >> Are my back aches a fitting-related issue or more of a muscle strength/flexibility issue?
    >
    >Could be either or both. Or just not enough miles.

    Approx 3500-4000 miles per year.

    >> Can I use a standard frame, or do I have to get a custom fitted frame? I can get a good deal on a
    >> 52 cm CAAD7 with complete Dura-Ace, so I hope this will do it, but maybe I need a longer top
    >> tube. Will a Trek be an alternative, or is there other options?
    >
    >I really believe most people can get a good fit on a stock frame if they search long enough. Your
    >height isn't unusual, and your long torso should be well suited to modern "stretched out" frames.
    >
    >You need to find a shop that knows how to do a fitting, and is willing to listen to you. Not one
    >that just takes measurements and uses formulas.

    Most of the bike shops in this area relies upon measurement&formula method, I'm afraid, and I prefer
    to buy used bikes if possible.

    >See: http://www.sbraweb.org/setup.htm

    Will check, thanks!

    >Hope you find a bike that works for you.

    Thank you for your time!

    Cheers, Kjell Arne

    --
    http://www.brumunddal-sk.idrett.no/ Remove your clothes if you want to answer by e-mail! favorite
    fruit. (Sheldon Brown, http://harriscyclery.com/
     
  4. > As I usually prefer to buy used bikes I hope to get some fitting advice in this group. I have
    > tried many of the web-based fitting calculators and they agree that with my 31 inch (78.5 cm)
    > inseam I need a 51 cm c-c frame. But for the top tube I get values of everything from 52 to 56-57
    > cm. I'm 5'8" tall (171.5 cm), so I have short legs and a relatively long torso. Body height
    > measured from the floor to the base of the sternal notch is 54.5" (138.5 cm).

    Very rarely would somebody 5'8" take a 51cm c-c frame (or 52cm center-to-top, as I believe the
    Cannondale is). Top tube clearance is only one aspect of fit, and probably the least important
    (although I will say that, for a cyclocross bike, it's more important than for normal road use).

    If you're 5'8" and have relatively short legs, the problem is that you then must have a fairly long
    torso (and probably relatively long arms as well). On a small frame, you'll probably find yourself
    hanging over the front end of the bike. Nearly always better to go for the larger frame, and you'll
    note that will also allow you to have the bars a bit higher, which tends to be how must
    cyclocrossers prefer them.

    > Are my back aches a fitting-related issue or more of a muscle strength/flexibility issue?

    Maybe yes, maybe no; quite possible that back aches are related more to other things you're doing
    that your cycling. I find my back feels far *better* after riding than otherwise and, as long as you
    stand up from time to time, cycling is a pretty good way to stretch *during* exercise. Heck, cycling
    cures almost everything in my book! But there's no harm in trying a different stem to see how it
    affects things, as they are *so* easy to swap out these days.

    I should also mention that static "fit" using numbers is only the beginning. It gives you a starting
    place, but you still need to have somebody who has a clue about fit actually watch you while riding
    (I always prefer seeing somebody actually ride a bike, even if only in a parking lot, because I find
    when I set them up indoors on a trainer, they tend to "perform" instead of relax).

    > Can I use a standard frame, or do I have to get a custom fitted frame? I can get a good deal on a
    > 52 cm CAAD7 with complete Dura-Ace, so I hope this will do it, but maybe I need a longer top tube.
    > Will a Trek be an alternative, or is there other options?

    Dura-Ace for cyclocross? Yikes! Pretty nice stuff, but not so sure you'll easily get the gearing you
    want, particularly if it's a hilly course. As I mentioned previously, the 52cm sounds like it might
    be a bit small, but your mileage may vary. Trek would certainly be an alternative, as would many
    others. We sell Trek ourselves, so if you were to give me a top-of-seat to center-of-bottom-bracket
    measurement, I could mock something up real quickly and see if the sizing appeared to make sense or
    was out of the ballpark (meaning that the seat would be so low that it would obviously be a non-fit
    for a given size frame, probably a 55cm).

    --Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com
     
  5. Kjell Arne Olsen wrote:

    > The cyclocross frame does not offer any standover clearance either, and after the first hour of
    > riding the lower part of my back start to ache. Not a serious pain, but more of being comfortable.
    >
    > As I usually prefer to buy used bikes I hope to get some fitting advice in this group. I have
    > tried many of the web-based fitting calculators and they agree that with my 31 inch (78.5 cm)
    > inseam I need a 51 cm c-c frame. But for the top tube I get values of everything from 52 to 56-57
    > cm. I'm 5'8" tall (171.5 cm), so I have short legs and a relatively long torso. Body height
    > measured from the floor to the base of the sternal notch is 54.5" (138.5 cm).
    >
    > Are my back aches a fitting-related issue or more of a muscle strength/flexibility issue?
    >
    > Can I use a standard frame, or do I have to get a custom fitted frame? I can get a good deal on a
    > 52 cm CAAD7 with complete Dura-Ace, so I hope this will do it, but maybe I need a longer top tube.
    > Will a Trek be an alternative, or is there other options?

    The principal frame dimensions that affect fit are the top tube length and the seat tube angle.
    There's more variability in top tubes.

    Select a frame with a top tube that allows a good position with a medium-length stem extension, say
    80-120 mm.

    People pay too much attention to seat tube length. This has nothing to do with how the bike will fit
    when you ride it, because the seatpost is adjustable!

    The only issue with seat tube length is that you should have _some_ standover clearance, but for a
    road bike you don't need much.

    When I fit folks who are proportioned as you are, sometimes their friends say the bike is too big,
    because they judge by the amount of seatpost showing. This is an error.

    I'm just the opposite, I've got a short torso, and long legs for my height. For me, on a stock
    frame, I wind up with a lot of seatpost showing, because taller frames will have top tubes that get
    me too stretched out. I also need a taller than usual stem, due to the lower top tube, but the
    result is a good fit.

    I explain this in more detail at http://sheldonbrown.com/frame-sizing.html

    Sheldon "Top Tube" Brown +-------------------------------------------------+
    | To stay young requires unceasing cultivation | of the ability to unlearn old falsehoods. | --
    | Robert A. Heinlein |
    +-------------------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone
    617-244-9772 FAX 617-244-1041 http://harriscyclery.com Hard-to-find parts shipped Worldwide
    http://captainbike.com http://sheldonbrown.com
     
  6. Woogoogle

    Woogoogle Guest

    Kjell Arne Olsen <[email protected]_CLOTHESbrumunddal-sk.idrett.no> wrote in message news:<[email protected]>...
    > "Arthur Harris" <[email protected]> wrote:
    >
    > >"Kjell Arne Olsen" wrote:
    > >> As I usually prefer to buy used bikes I hope to get some fitting advice in this group. I have
    > >> tried many of the web-based fitting calculators and they agree that with my 31 inch (78.5 cm)
    > >> inseam I need a 51 cm c-c frame. But for the top tube I get values of everything from 52 to 56-
    > >> 57 cm. I'm 5'8" tall (171.5 cm), so I have short legs and a relatively long torso. Body height
    > >> measured from the floor to the base of the sternal notch is 54.5" (138.5 cm).
    > >
    I am the same height but my legs are 2 cm shorter. I got a cross frame from a local builder that was
    *not* a custom frame with a 48cm c-t and 54cm top tube.
     
  7. Chris Dorn

    Chris Dorn Guest

    One bike manufacture that makes bikes with long top tubes is Airborne see
    http://www.airborne.net/eready/janette/abhome.asp I ususally ride a 58cm frame, but in their sizing
    I ride a 56cm and use a short stem. You can usually pick up a used frame pretty cheap. They will
    also let you recirtify the frame for $150.00 so that you can have the lifetime guarantee also. Their
    customer service is much better now that Huffy sold them back to the original owner, Jamie Raddin.
    Take Care Chris
     
  8. << I have tried many of the web-based fitting calculators and they agree that with my 31 inch (78.5
    cm) inseam I need a 51 cm c-c frame. But for the top tube I get values of everything from 52 to 56-
    57 cm. I'm 5'8" tall (171.5 cm), so I have short legs and a relatively long torso. Body height
    measured from the floor to the base of the sternal notch is 54.5" (138.5 cm). >><BR><BR>

    Formulas are only a place to start. Unless they measure your femur length, which detemines seat tube
    ANGLE, they are not complete. Once your position relative to the BB is found, only then can you
    determine top tube and stem LENGTH and difference between top of saddle to top of hbars.

    Inseam means little.

    Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
    (303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"
     
  9. "Mike Jacoubowsky" <[email protected]> wrote:

    >> As I usually prefer to buy used bikes I hope to get some fitting advice in this group. I have
    >> tried many of the web-based fitting calculators and they agree that with my 31 inch (78.5 cm)
    >> inseam I need a 51 cm c-c frame. But for the top tube I get values of everything from 52 to 56-57
    >> cm. I'm 5'8" tall (171.5 cm), so I have short legs and a relatively long torso. Body height
    >> measured from the floor to the base of the sternal notch is 54.5" (138.5 cm).
    >
    >Very rarely would somebody 5'8" take a 51cm c-c frame (or 52cm center-to-top, as I believe the
    >Cannondale is). Top tube clearance is only one aspect of fit, and probably the least important
    >(although I will say that, for a cyclocross bike, it's more important than for normal road use).

    Maybe I did hide the fact well, but I'm looking for a road frame as a replacement for the
    cyclocross frame.

    >If you're 5'8" and have relatively short legs, the problem is that you then must have a fairly long
    >torso (and probably relatively long arms as well).

    Yes. my arms are quite long, too.

    >On a small frame, you'll probably find yourself hanging over the front end of the bike. Nearly
    >always better to go for the larger frame, and you'll note that will also allow you to have the bars
    >a bit higher, which tends to be how must cyclocrossers prefer them.

    Very wise words, but for example a Trek has a longer tob tube, isn't it so?

    >> Can I use a standard frame, or do I have to get a custom fitted frame? I can get a good deal on a
    >> 52 cm CAAD7 with complete Dura-Ace, so I hope this will do it, but maybe I need a longer top
    >> tube. Will a Trek be an alternative, or is there other options?
    >
    >Dura-Ace for cyclocross? Yikes! Pretty nice stuff, but not so sure you'll

    As stated above, it's a road frame, 2003 model BTW.

    >mileage may vary. Trek would certainly be an alternative, as would many others. We sell Trek
    >ourselves, so if you were to give me a top-of-seat to center-of-bottom-bracket measurement, I
    >could mock something up real quickly and see if the sizing appeared to make sense or was out of
    >the ballpark

    Top-of-seat to center-of-BB measured along the center of the seat tube is 68.8 cm, or 27 inches.

    >(meaning that the seat would be so low that it would obviously be a non-fit for a given size frame,
    >probably a 55cm).

    This is very nearly a problem with the Cannondale CC, which has a Campa seatpost that is rounded off
    towards the saddle, so that I can barely fix it. I could change the seatpost, of course..

    I took the bike into my livng room for these measurements (the snow is deep outside..), and noticed
    that saddle maybe has been raised a little bit too much. I lowered it from 69.5 cm to get the
    abovementioned measurement. This could be one possible explanation for my back aches, maybe?

    Good to see so many of the good people here at r.b.t help. Many thanks!

    Cheers, Kjell Arne

    --
    http://www.brumunddal-sk.idrett.no/ Remove your clothes if you want to answer by e-mail!
     
  10. Sheldon Brown <[email protected]> wrote:

    >Select a frame with a top tube that allows a good position with a medium-length stem extension, say
    >80-120 mm.
    >
    >People pay too much attention to seat tube length. This has nothing to do with how the bike will
    >fit when you ride it, because the seatpost is adjustable!
    >
    >The only issue with seat tube length is that you should have _some_ standover clearance, but for a
    >road bike you don't need much.

    With the cycling shoes on and stepping over the frame, I'm able to move the top tube max 1 cm
    towards my private parts.

    >When I fit folks who are proportioned as you are, sometimes their friends say the bike is too big,
    >because they judge by the amount of seatpost showing. This is an error.
    >
    >I'm just the opposite, I've got a short torso, and long legs for my height. For me, on a stock
    >frame, I wind up with a lot of seatpost showing, because taller frames will have top tubes that get
    >me too stretched out.

    And I wind up with very little seatpost showing with the Cannondale CC, which has a Campa seatpost
    that is rounded off towards the saddle, so that I can barely fix it. I could change the seatpost,
    of course..

    >I explain this in more detail at http://sheldonbrown.com/frame-sizing.html

    I have already visited this and many other of your excellent web articles. Many thanks!

    Cheers, Kjell Arne

    --
    http://www.brumunddal-sk.idrett.no/ Remove your clothes if you want to answer by e-mail!
     
  11. [email protected] (Qui si parla Campagnolo) wrote:

    >Formulas are only a place to start. Unless they measure your femur length, which detemines seat
    >tube ANGLE, they are not complete. Once your position relative to the BB is found, only then can
    >you determine top tube and stem LENGTH and difference between top of saddle to top of hbars.
    >
    >Inseam means little.

    Yea, I know. My femur length, measured the Bsn (Edward Zimmermann) way is 57.5 cm.

    Cheers, Kjell Arne
    --
    http://www.brumunddal-sk.idrett.no/ Remove your clothes if you want to answer by e-mail!
     
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