Crappymonkey

I had my girlfriend take measurements of me according to the Competitive Cyclist Fit Calculator. These were the results..

The Competitive Fit (cm)
Seat tube range c-c: 53.4 - 53.9
Seat tube range c-t: 55.1 - 55.6
Top tube length: 57.3 - 57.7
Stem Length: 11.8 - 12.4BB-
Saddle Position: 75.4 - 77.4
Saddle-Handlebar: 56.0 - 56.6
Saddle Setback: 4.1 - 4.5

The Eddy Fit (cm)
Seat tube range c-c: 54.6 - 55.1
Seat tube range c-t: 56.3 - 56.8
Top tube length: 57.3 - 57.7
Stem Length: 10.7 - 11.3BB-
Saddle Position: 74.6 - 76.6
Saddle-Handlebar: 56.8 - 57.4
Saddle Setback: 5.3 - 5.7

The French Fit (cm)
Seat tube range c-c: 56.3 - 56.8
Seat tube range c-t: 58.0 - 58.5
Top tube length: 58.5 - 58.9
Stem Length: 10.9 - 11.5BB-
Saddle Position: 72.9 - 74.9
Saddle-Handlebar: 58.5 - 59.1
Saddle Setback: 4.8 - 5.2

I want to order a BMC Race Master SLX01 from Competitive cyclist. Here's the bike's geometry...

Size Seat Tube (c-t) Top Tube Seat Angle Head Tube Length Head Angle
49 50.0 53.0 73.5 11.5 72.0
52 52.5 54.5 73.5 14.0 72.0
54 54.5 55.5 73.5 15.5 72.0
56 56.5 57.0 73.5 17.0 72.5
58 59.7 57.9 73.5 19.0 73.0
61 62.9 59.4 73.5 22.0 73.5


I usually ride a 56cm bike and I'm 5'11" with a 32.5" inseam. According to the calculator I should be ordering a 54cm bike. What do you all think I should go with? The only built up racemaster in the area is a 52cm

ciocc_cat

We're about the same size - I'm just over 5' 10.5" and have a 32.625 inseam. I also ride a 56 cm frame and prefer an old school "Eddy Fit" (which really wasn't "old school" back when I was racing Cat 4). Contemporary frames are typically sized smaller to provide a more aerodynamic/aggressive position, but not everybody races.

Edit: I should probably mention that I ride an early 1980s vintage lightweight steel frame rather than a modern carbon fiber frame.

Crappymonkey

That's what I figured too.

The online help person at CC told me he was the same size as me and rides a 54cm. He finds the top tube too long on a 56cm. All the fittings suggest a 57cm+ top tube for me which is on the 56cm. I'm so confused

longbeachgary

54 is too small. Are you racing?

Crappymonkey

Not in the immediate future. I'm upgrading from a 56cm '87 Cannondale criterium. I need to get back in shape first. I was hit by a car last August while riding to work and the only riding I've done since then has been on my trainer.

teterider

You're reading the wrong number.

You fit a bike (in most basic fitting) by the effective top tube, so that would be the 56cm with the 57cm top tube, and maybe the 58 with the 57.9cm top tube (but at 5'11" the 58cm is less likely). But that bike has a steep seat tube angle. If you need lots of setback that may be a problem without a high setback post - oh nevermind, your setback is short. There are lots of variables to look at in a geometry table and not all bikes can be tailored to your ride characteristic requirements.

Also, I caution anyone buying a bike that asks for a size through an internet forum and doesn't understand a fit calculator and geometry tables. Perhaps do a lot more research on the subject or get physical fitting help.

Dean V

Why do they show such large variation in saddle heights? I would of thought this is one of the more critical measurements and also relatively easy to determine from your inseam.
I just can't see how you could trust a calculator that gives all the measurements to supposedly within 0.5cm and then gives 2cm variation on saddle height.

Crappymonkey

Thanks for the info. I was about to order the 56cm because the measurements are almost dead on with my current bike when I figured I'd try the fit calculator from the site. I was suprised to see it suggesting a 54cm so I figured I'd ask about it here.

They say this on the site...

BB-Saddle Position
This measurement is along the seat tube, from the center of the bottom bracket spindle to the top of the saddle. It is an ideal starting point for saddle height. Given the varying differences of cleat and pedal heights, and given the varying differences in the thickness of saddles, the BB-Saddle position has a broad range of 2cm.

chadteck

Pedal Force's calculator has given me what I feel are the best results of any fit calculator I've used. It's also the only one I've seen that actually has an input for how much drop you want. Try it out and see what you end up with. My opinion is that the 54cm isn't out of the question for your height if you prefer an aggressive position.

DaveSSS 

Post your actual saddle height, no some inaccurate guess from a fit calculator. If you know your saddle height and a preferred saddle to bar drop, it's easy to pick the proper head tube length. The head tube length will vary a lot more than the frame reach, in most cases.

An 83cm inseam should yield a saddle height around 73cm. That means that your legs are on the short side (same as mine at 5'-6.5" tall). Even the 52cm frame would have a little more head tube than I want. The 54cm would probably be the best choice, unless you want a lot of saddle to bar drop (like I do).

Looigi

I tried the Competitive Cyclist fit calculator and it came up with some weird sizing for me, and I'm a very average 5' 10". I'm not sure why. The Wrench Science calculator worked correctly. You might try it as see how it compares to CC.

https://www.wrenchscience.com/road

dmcdam

I'm also in Toronto - have you calculated the shipping and possible duties importing into Canada? I'm curious as to how it all works out.

Crappymonkey

According to https://thefinalcost.com/ it comes to $2441. I'd have it sent to https://www.cbiusa.com/ and pick it up in Niagara Falls myself to avoid paying the $79 UPS broker fees and $8 dispursement.

Crappymonkey

It came up with this....

WS Recommended Sizes Frame Size center-to-center: 54 cm Frame Size center-to-top: 56 cm Overall Reach: 71.00 cm Saddle Height: 73.29 cm Handlebar Width: 42 cm

wfrogge

I would go with the 54.... You can always make up for a small bike with a stem/seat post but if its too big you are SOL

Crappymonkey

That's what I'll be doing.

On an unrelated note I was in a LBS today and they had a Cervelo R5ca. I picked it up and it was insanely light. It was 12 pounds! Not worth $20,000 in my opinion but an interesting peice of engineering.