Bike fit- pros vs. the rest of us

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pdlpsher1
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by pdlpsher1

I'm not knowledgeable on bike fitting but I can't help to notice the somewhat strange fit on pro bikes. Many pros are riding on 130m-140mm stems and frame sizes that seem to be 2-4cm too small. Take Peter Sagan as an example. He's 6' tall and rides a 56cm. Another example is Ian Stannard who's 6'3" and rides a 57.5cm. I'm embarrassed to disclose my physical attributes and the bike I ride :oops: My saddle is barely sticking out of the frame! Could someone tell me if the 'pro' fit is truly the best fit or do you agree with me that they are riding too small of a frame!

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Kurets
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by Kurets

6' (183cm) is pretty standard for a 56 frame. With most pros riding production frames you run into a problem. The manufacturer obviously wants to market the frame to the public, most of whom are not co.fortable with a "long and low" position. Therefore you make the head tube tall enough that people can avoid spacers while still having a comfortable saddle to bar drop.
But, the tall headtube is the opposite of what a racer wants. So, to compensate for the tall headtube a racer must get a smaller frame to get the bars low enough. The smaller frame is then too short so a long stem is necessary to make up for the short top tube.
As a side note, I am 183cm, ride a 56 frame, 9.5cm saddle to bar drop and a 120mm stem. But then I spend 10-12 hours on the bike each week.

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SLCBrandon
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by SLCBrandon

I'm 6'1.5" (187cm?) and also ride a 56cm ViAS (and most other brands bikes) with a 125mm stem (basically a 130 in normal stems) and prefer it to my previous 58's in every way. Most people I know that race are on what you might consider too small of a bike.

For the most part it allows the ability to achieve the amount of saddle to bar drop you want. I was on the lowest possible setup on the 58 ViAS and still wanted to go 1cm lower. I now have that on the 56 and much prefer this fit to the 58.

wingguy
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by wingguy

pdlpsher1 wrote:Could someone tell me if the 'pro' fit is truly the best fit or do you agree with me that they are riding too small of a frame!


It usually (not always) is the best fit for them, it's almost certainly not the best fit for you (if you were their height). Pros are fitter than you, faster than you, spend much more time on the bike than you... why would they fit the same as you?

The two major reasons for riding smaller frames are more drop (more aero) and longer stem for stable high speed handling.

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Calnago
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by Calnago

They'd get better high speed handling with a longer wheelbase. Main reason for smaller frames is like someone said, to get lower and they compensate for the length with a longer stem. Cycling pros usually have very little weight (compared to the rest of us) above the waist, or in general for that matter and can throw their body over the front end without affecting the center of gravity nearly as much as some of us with a little more "girth" up top. Also, Sagan, since you mentioned him specifically, used to ride custom frames which had a longer top for the frame size, enabling him to get long and low. But I don't think he has particularly long legs for his height so makes sense. But at the end of the day, you need to ride what works for you, not what someone else rides. So to answer your question, at least from my personal point of view is No, a "pro fit" (whatever that is) is not at all necessarily the best fit for you and yes, I would agree that some pros might actually be riding too small a frame, but they've ridden long enough to know what they like for better or worse. So for them, regardless of what anything else thinks, it's right.


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yongkun
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by yongkun

Smaller frame is lighter and also tend to be stiffer


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Nefarious86
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by Nefarious86

SLCBrandon wrote:I'm 6'1.5" (187cm?) and also ride a 56cm ViAS (and most other brands bikes) with a 125mm stem (basically a 130 in normal stems) and prefer it to my previous 58's in every way. Most people I know that race are on what you might consider too small of a bike.

For the most part it allows the ability to achieve the amount of saddle to bar drop you want. I was on the lowest possible setup on the 58 ViAS and still wanted to go 1cm lower. I now have that on the 56 and much prefer this fit to the 58.

This is interesting because on the calculator for fit I'm either a 58 with a slammed 125mm setm or a 56 with a 135mm stem and 30mm of spacer. The 58 gives me no room to come down. Currently on 58cm Tarmacs.
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bas
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by bas

That calculator can be deceiving, told me a 54 with the 25mm riser bar and 15mm of spacer, actual specs are coming out 54 with flat bar and no spacers. Headset cap is deceptively tall. I'm coming from a 56cm Trek in H1 fit.

Nefarious86
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by Nefarious86

56 slammed with 25mm bars will do me haha
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SLCBrandon
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by SLCBrandon

The calculator is a bit deceptive, I agree. I just took a known fit, a geo chart and a stem angle calculator and dialed fit in. Set it up how I had worked it out based on the above and it was exactly what I was after.

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by Nefarious86

Ok, maths it is :)
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pdlpsher1
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by pdlpsher1

Thanks guys. Your responses make a lot of sense. Here's Alex Howe's bike....looking more like a 'normal' fit :D He's 5'11" and 144lbs. I believe this is a size 54cm.

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rms13
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by rms13

I'm just under 5'11 and I ride a 54 with 120mm stem.

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Lelandjt
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by Lelandjt

bas wrote:That calculator can be deceiving, told me a 54 with the 25mm riser bar and 15mm of spacer, actual specs are coming out 54 with flat bar and no spacers. Headset cap is deceptively tall. I'm coming from a 56cm Trek in H1 fit.

Edit: Nevermind, realized you're talking about the vias calculator.

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pdlpsher1
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by pdlpsher1

Here's Joey Rosskopf's 54cm steed. He's 6'2" and uses a 175mm cranks. I ride a 54cm and a 100mm stem, and I'm nowhere near 6'2" :oops: Here's a question. I'm also down to a single spacer (or reducer) below the stem. If I wish to drop the stem even further it is even possible? My reducer/spacer is slighter shorter than the one pictured here. I don't think I can just remove the reducer as the upper headset bearing is larger than the stem. I guess I could also get a -17 stem too.

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