Tried the Competitive Cyclist fit calculator, but the result for a tri fit is confusing, I get a top tube recommendation of 50-52 cm only. That would put me on a very small frame, I mean I’m 6’2" tall. The same data for an Eddy road fit results in a 60 cm top tube. http://www.competitivecyclist.com/Store/catalog/fitCalculatorBike.jsp
Fit Style The Aero Fit
Top Tube Length 50.1 - 52.1 Cm
Stem Length 8 - 10 Cm
BB Saddle Position 80.6 Cm
Saddle Pedal 97.8 Cm
Saddle Ground 105.6 Cm
Cranklength 177.5 Cm
Aero Bar Size L
Aero Bar Drop Minimal 8.3 Cm
Aero Bar Drop Moderate 13.9 Cm
Aero Bar Drop Intense 16.3 Cm
Aero Bar Drop Maximal 20.4 Cm
Pad Ground Minimal 97.3 Cm
Pad Ground Moderate 91.6 Cm
Pad Ground Intense 89.2 Cm
Pad Ground Maximal 85.2 Cm
Inseam 89.5 Cm
Trunk 75 Cm
Forearm 38.5 Cm
Arm 69 Cm
Thigh 62.5 Cm
Lower Leg 59.5 Cm
Sternal Notch 155.5 Cm
Total Height 188 Cm
Fit StyleThe Aero Fit
Top Tube Length 43.3 - 45.3 Cm
Stem Length 8 - 10 Cm
BB Saddle Position 76.5 Cm
Saddle Pedal 93.7 Cm
Saddle Ground 101.5 Cm
Cranklength 175 Cm
Aero Bar Size M
Aero Bar Drop Minimal 6.3 Cm
Aero Bar Drop Moderate 11.7 Cm
Aero Bar Drop Intense 14 Cm
Aero Bar Drop Maximal 17.8 Cm
Pad Ground Minimal 95.2 Cm
Pad Ground Moderate 89.8 Cm
Pad Ground Intense 87.5 Cm
Pad Ground Maximal 83.7 Cm
Inseam 85 Cm
Trunk 63 Cm
Forearm 35 Cm
Arm 62 Cm
Thigh 62 Cm
Lower Leg 55.5 Cm
Sternal Notch 146 Cm
Total Height 179 Cm
Here are the spec’s for my bike:
Frame size* XS SM MD LG
TT Top Tube 510 530 555 570
ST Seat Tube 490 490 510 530
HT Head Tube 80 80 100 120
HA Head Angle 72° 72.5° 73° 73°
SA Seat Angle (TT/Tri) 76°/79° 76°/79° 76°/79° 76°/79°
CS Chain Stay 400 400 400 400
FO Fork Offset (Rake) 43 43 43 43
BB Bottom Bracket Drop 70 70 70 70
Handlebar Width 400 400 400 400
Stem Length 100 100 110 120
Crank Length 170 172.5 175 175
S Stack 490 490 510 530
R Reach 390 410 430 450
I went for the large with a 70mm stem, and it’s a great fit.
Here are the specs for my road bike: I got the medium. Apart from the seat to bar drop, my position measurements are almost identical when riding hoods (road) compared to base bar (tri).
FYI here are the results from CC back in 2011. Notice they are the same, apart from the top tube which seems to be short on the new version of calculator. My guess is they are accidentally subtracting the stem range from the top tube range.
The Aero Fit
Top Tube Range: 51.5 - 53.5
Stem Length Range: 8.0 - 10.0
Saddle-Bottom Bracket Position: 76.5
Saddle-Pedal Position: 93.7
Saddle-Ground Position: 101.5
Cranklength: 175.0
Aero Bar Size: M
Saddle-Aero Bar Pad Drop Minimal: 6.3
Saddle-Aero Bar Pad Drop Moderate: 11.7
Saddle-Aero Bar Pad Drop Intense: 14.0
Saddle-Aero Bar Pad Drop Maximal: 17.8
Pad-Ground Position Minimal: 95.2
Pad-Ground Position Moderate: 89.8
Pad-Ground Position Intense: 87.5
Pad-Ground Position Maximal: 83.7
When I was frame shopping, they gave me some funky results and said I needed a small too. I’m not huge, but I’m 5’11", so the small made me a little dubious of the results. I called and the guy at CC brushed aside the calculator’s results at first, but then he noticed that they only had a small and a large of the frame I wanted. So he said a small or a large would work. No mention of a medium. I followed my coach’s advice and held out for a medium, which showed up, I guess, after someone made a return to CC.
The moral of the story was that the calculators I found online were not all that helpful. (The Zinn calculator was putting me on a large with some 182.5 cranks.) I’m thinking they can be useful because they force you to make a bunch of measurements that you might not otherwise make, but someone who knows something about bike fitting will give you better advice.
