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Old 05-05-10 | 01:49 PM
  #4  
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Loose Chain
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Joined: Sep 2009
Posts: 2,067
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From: USA

Bikes: 84 Pinarello Trevisio, 86 Guerciotti SLX, 96 Specialized Stumpjumper, 2010 Surly Cross Check, 88 Centurion Prestige, 73 Raleigh Sports, GT Force, Bridgestone MB4

Yes there is but it is not perfect but for normal people, normal being a mesomorph build with proportional legs, arms, torso, the calculation of .883 X PBH = SH where PBH is your pubic bone height in bare socks, SH is the center of your saddle height in line with the seat tube. This formula is pretty darn accurate with some adjustment made for shoes, paddles, foot size and your particular body. Again, for a level top tube bike, the seat tube would then be backed out that gives you approx 1.5 to 2 inches stand over in stocking feet. Whatever frame size (seat tube length that is) then get a bike with a similar top tube length and a 100cm stem, however, obviously, there are huge variations in body types and so IMO, the bike that fits you is one that has a top tube that is comfortable with a reasonable stem length of 90 to 120cm and to which you can get leg extension per the equation above.

The "Rivendale" fit sounds a lot like the "French" fit described in that often given web link. A too big frame with high bars and a vertical position on the bike. I find this the least comfortable positions. I have one of my four ride-able bikes with the Eddy fit and the others are Competitive fit or what I guess we might call, Competive Plus size because I still have the bar tops low-er than the Eddy fit but not extremely low but in one of my bikes. No expert for sure here, just what I have seen on myself and a few others.

LOL, back before mtb seat posts, with a Campy post, I was told that the frame was right when the seat post was pulled to the NO GO line and your leg extension was correct.

Last edited by Loose Chain; 05-05-10 at 02:00 PM.
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