# Just how accurate is the Competitive Cyclist fit calculator?



## Honda Guy (Jan 20, 2016)

Hi all,

I sized my mountain bike's frame in the past using the Competitive Cyclist fit calculator. I want to get into road biking and I'm buying used. There's a 57cm Bianchi (57cm seat tube c-t, 56cm virtual top tube) for a great price near me, but that just doesn't seem right being 6 foot tall and hearing what others ride.

According to the calculator, I should be riding a frame with a 58-58.5cm seat tube and a 55.6-56cm top tube, which means the Bianchi is pretty close to ideal. However, that just doesn't seem right. From what I've read, a few people my height ride 56cm top tube frames fine, but those people seem to be in the minority.

For those who have used the fit calculator, how did it work out for you? Do you feel like it was accurate?


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## Srode (Aug 19, 2012)

It seems pretty accurate from my experience with it. The size recommended for you by it seems right to me. I have 2 56 bikes and one 58 and they all fit fine, and I'm a tad over 6'. The fit guide recommended a 56 for me when I was shopping for an RLT9 Niner frame and it was easy set up to fit me.


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## Jon D (Apr 11, 2011)

I'm a tad under 6' and ride 56 as base size. Trek Domane is primary bike.


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## bikerjulio (Jan 19, 2010)

If you have normal body proportions (which the calculator takes into account if I remember), then that result seems about right. 

I'm almost 6' 2" and would normally ride a 57.5 cm ETT.

If you have never ridden a road bike, then there's going to be a settling in period for you to feel comfortable. Obviously, saddle height, stem length, bar height are all things that need to be right as well. Getting the correct setup is vital.


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## factory feel (Nov 27, 2009)

6' 2" riding 58's as a general rule.

110mm stems with normal setback seatposts.


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## ericm979 (Jun 26, 2005)

Their fit calculator gave me whack numbers but that was a while ago.

I'm 6' with a 35" cycling inseam. My bikes are in the 56.5-57cm ETT range with 73 degree seat tubes (that matters). Stems are 110 or 120mm.


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## MMsRepBike (Apr 1, 2014)

It's terrible, the worst available.

Pedal Force super-light carbon bicycle

The above is much better.

The CC calculator is horrible. It doesn't even work of off correct fit principles. Never, ever fit a bike off of tube lengths. I don't even want to know how many people bought the wrong size bike because of it.

I remember years ago I bought a wrong size bike because of it. I remember emailing them and asking them what the **** was wrong with them and their calculator. I went into full detail laying out all of my measurements, their results, the bike I got with their results, and how it fit. It was a disaster. I could only ride the bike a couple times before I had to sell it for a huge loss. So much for fitting yourself online... So they claim if you have any issues with the calculator to email them about it and they'll help. Well they never got back to me. I didn't give up either, I wanted answers, but they can't give them because the program sucks. Like I said, it's flawed in it's design right from the get.

My advice is to never, ever use the CC calculator.

Oh, and when I hear these keyboard warriors telling me they can fit a bike by it's top tube length and can tell me if it's a "Eddy or French Fit" or not by looking at geometry, I laugh out loud. Nobody can fit a bike with any tube length properly and there is no such thing a an Eddy fit or a French fit, the CC calculator is complete trash.

In case you're wondering, Stack and Reach are the only measurements used to fit a frame. The ONLY ones. The rest are ride characteristics and have nothing to do with fit.


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## Jay Strongbow (May 8, 2010)

Another question to concern yourself with is how accurate are self measurements.


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## MMsRepBike (Apr 1, 2014)

Jay Strongbow said:


> Another question to concern yourself with is how accurate are self measurements.


They're no good. And even having someone measure you isn't that great. I suggest having two people measure you. And even then having each one measure twice is best.

The one good thing CC has going is the short videos about taking measurements.


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## factory feel (Nov 27, 2009)

stack and reach, I agree.

everything else is minutia.

I like a 590 stack and a 400 reach, thereabouts.


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## ROAD&DIRT (Mar 27, 2009)

MMsRepBike said:


> It's terrible, the worst available.
> 
> Pedal Force super-light carbon bicycle
> 
> The above is much better.


Looks like good tool.... I'll have to try it and compare the results to what I'm riding now .


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## Henry Chinaski (Feb 3, 2004)

MMsRepBike said:


> It's terrible, the worst available.
> 
> Pedal Force super-light carbon bicycle
> 
> ...


How do you really feel? 

I got fit to a 57cm Bianchi Nuovo Racing in 1983 at age 15 by the old Italian shop owner. Basically checked my standover and then he watched me pedal it around the back parking lot and told me it was the right size. I had pretty much reached by current 5' 11" height by then. Since then I've had a ton of bikes, including several custom frames. My basic fit has not changed much at all. However, 32 years later I'm a bit less flexible, and push smaller gears. My position has moved forward a bit and I don't want to reach quite as far. So basically instead of the standard Campy-style layback post and 11cm and 12cm stems I used back then, I now have a no-setback Thomson post and a 10cm stems on most of my bikes. 

Anyway, this stuff isn't really rocket science. I think people overthink it.

Only thing I changed on that first Bianchi was the seat. Shop owner said, "you're skinny, you should ride a Concor." Been using them ever since.


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## GKSki (Nov 12, 2014)

Provide Inseam, Thigh(seated), Lower Leg(seated), Trunk(seated), Arm, Forearm and shoe size and I will run them in my program which is a combination of Eddie Borysewicz's theories and those of Bernard Hinault. 

You'll get back frame size (c to c), saddle height (c to c), crankarm length, cleat position, saddle setback, saddle to bar and stem drop. Provide a list of possible top tube lengths and seat tube angles, and the program will provide stem size and seatpost setback.


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## Henry Chinaski (Feb 3, 2004)

GKSki said:


> Provide Inseam, Thigh(seated), Lower Leg(seated), Trunk(seated), Arm, Forearm and shoe size and I will run them in my program which is a combination of Eddie Borysewicz's theories and those of Bernard Hinault.
> 
> You'll get back frame size (c to c), saddle height (c to c), crankarm length, cleat position, saddle setback, saddle to bar and stem drop. Provide a list of possible top tube lengths and seat tube angles, and the program will provide stem size and seatpost setback.


Problem with that is my measurements would be the same when I was 18, racing and riding 250 miles a week as they are today when I'm 47, not racing and getting in 75 miles on a good week. So my frame size (c to c) and saddle height (c to c) would be right, my cleats position hasn't changed much, but everything else has moved around a bit. Crankarms are whatever feels good, usually between 170 and 175 for road.


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## Honda Guy (Jan 20, 2016)

GKSki said:


> Provide Inseam, Thigh(seated), Lower Leg(seated), Trunk(seated), Arm, Forearm and shoe size and I will run them in my program which is a combination of Eddie Borysewicz's theories and those of Bernard Hinault.
> 
> You'll get back frame size (c to c), saddle height (c to c), crankarm length, cleat position, saddle setback, saddle to bar and stem drop. Provide a list of possible top tube lengths and seat tube angles, and the program will provide stem size and seatpost setback.


Thanks! It'll be interesting to see how the two recommendations compare.

Inseam: 33.5"
Thigh: 24.4" (measured from kneecap to butt, not to inseam)
Lower Leg: 22"
Trunk: 25.5"
Arm: 26.5"
Forearm: 14.5"
Shoes: 47

Possible Frames:
Bianchi Volpe: 560mm virtual top tube, 548mm actual, 73.5 STA

Charge Plug 4: 559mm virtual top tube, 540mm actual, 73 STA


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## GKSki (Nov 12, 2014)

Honda Guy said:


> Thanks! It'll be interesting to see how the two recommendations compare.
> 
> Inseam: 33.5"
> Thigh: 24.4" (measured from kneecap to butt, not to inseam)
> ...


Bianchi

Results:Frame SizeSaddle (C to C)Height (C to C)crankarm lengthcleatsaddle setbacksaddle-barstem dropstem sizeseatpost setback55.308575.30465172.511.17.3354.867.5511 to 13.515.71

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</tbody>Charge

Results:Frame SizeSaddle (C to C)Height (C to C)crankarm lengthcleatsaddle setbacksaddle-barstem dropstem sizeseatpost setback55.308575.30465172.511.17.3354.867.5510.5 to 1316.17

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</tbody>


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## duriel (Oct 10, 2013)

If you have long legs, you go a little smaller. If you have short legs, go a little bigger.


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## Herkwo (Nov 8, 2002)

Honda Guy said:


> Hi all,
> 
> There's a 57cm Bianchi (57cm seat tube c-t, 56cm virtual top tube) for a great price near me, ...


Given the above... Why all the discussion? You are close to the size in the calculator and have access to the bike. Go test it out and see how it feels.


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## GKSki (Nov 12, 2014)

Honda Guy said:


> Thanks! It'll be interesting to see how the two recommendations compare.
> 
> Inseam: 33.5"
> Thigh: 24.4" (measured from kneecap to butt, not to inseam)
> ...


How did my calculations work out for you?


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## 9W9W (Apr 5, 2012)

I used the CC calculator when sizing myself for my first internet order bike. I used a laser level and a girlfriend to take pretty accurate measurements. I remember there were three "fits" to pick from in range (french, eddy...) not knowing what's what I picked the middle one. The bike I bought was ultimately just a shade too small, but rideable. I am six feet. That bike had a stack of 568 and reach of 386, 55.6 effective 73.5STA, I used a 120 stem, compact bar and SRAM hoods (which I think are shorter and feel smaller/closer than Shimano) and felt cramped. Further proof that it was just too small was the fact that it was an endurance frame, which is supposed to be pretty upright, yet the way I had it setup with tons of seatpost showing and spacers...and still had a pretty aggressive drop from seat to bar. I rode that bike for a years, but was never really comfortable. 

I now ride a 58 frame, 57.5 effective, 73.5STA 384 stack, 402 reach with 110/120 stem and bar. I am nice and stretched out which I like, but do keep in mind that I stretch daily (....okay every other day) and can touch my toes with no problem. I am six feet and not one sixteenth inch taller over six feet. Me thinks frame sizing has a lot to do with fitness, more than people think. I see a lot of jacked up fits out there and a lot of wonky bike setups. How do I know that the guy telling me a 55 at 6' feels fantastic isn't riding with a tower full of spacers, a positive stem, and is bolt upright to nurse his stiff back? I don't. 

I dealt with the same when purchasing a new to me used bike recently. People screaming on the interwebz to size down! size down! To me, remembering the above slightly too small of a bike, it didn't feel right to get into a bike that was very similar in dimensions to that one (same STA, something like .5mm longer in the TT).... I disregarded the forums and purchased the larger frame, and am very happy with it. 

I think you're certainly within the size range for a 57. Depending on your choice of handlebars your reach to the hoods can easily change by 10mm. 

Use STACK and REACH to compare frames...everything else is just a piece of the puzzle. 

Did you check out the bike OP? With us?


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## Peter P. (Dec 30, 2006)

Henry Chinaski said:


> How do you really feel?


Exactly.

My recommendation is to try a few different sizing and measuring methods found on the web or in books. Once you see two or three results agree, you're pretty damn close.

That would be a good reference list to compile; known fitting methods, whether in a book or on-line.

Here is retired, respected frame builder Dave Moulton's on-line chart. Note it uses height, inseam, and shoe size in a unique way, but it works for me. The only adjustment is, he specs shorter top tubes combined with longer stems for the same essential result (at least in my case). So as long as the sum of the top tube and stem remain the same, you can use his chart reliably.

Another on-line calculator is from framebuilder Lennard Zinn. He shows how to take the required measurements elsewhere on his web site.


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## Honda Guy (Jan 20, 2016)

Hey all,

I went to the bike shop to check out the Volpe and found out that it had been sold. I ended up trying out the 56cm Charge Plug that I was considering and a 58cm 2010 Trek 2.1 with 3x10 105 that I saw there last time. The Plug felt a little short and uncomfortable for my neck, and the Trek felt more stretched out and natural. It has a 57cm effective top tube, and according to Trek's sizing charts, I'm right in the middle of that size range. Although it's not the best way to size a bike, I ended up going with it and have no regrets doing so. 

It needs a little work and has a wheelset off a Scott, but for $340, I'm happy with it. I feel like the Volpe or the Plug would have been too commuter/touring oriented for what I'll actually end up doing with it.

It has some Continental Sport Contacts that're nearly bald. Any suggestions for a good tire?


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## Herkwo (Nov 8, 2002)

Honda Guy said:


> Hey all,
> 
> Any suggestions for a good tire?


Here are a couple: (I recommend a 25mm)
Vittoria Rubino II - $19 ea .
Vittoria Rubino Pro II Tire - Tires - Clincher - Excel Sports
Or if you can afford them... Vittoria Corsa CX III - $38 ea.
Vittoria Open Corsa CX III Tire - Tires - Clincher - Excel Sports


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