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Discussion Starter · #1 ·
Hello,

I've been reading many posts regarding frame sizing and I've gain a lot knowledges from them. Thankyou all:) I'm thinking about a purchase of TST titanium frame 56cm(C-T) and I want some advice from you experts:D

First of all, here is my measurements.
Inseam 85 cm
Trunk 66 cm
Forearm 37.5 cm
Arm 72 cm
Thigh 59 cm
Lower Leg 55 cm
Sternal Notch 148.5 cm
And I'm 5'11" 175lbs

And this is what I get from CC calculator

Seat tube range c-c 55.1 - 55.6
Seat tube range c-t 56.8 - 57.3
Top tube length 57.6 - 58.0
Stem Length 12.2 - 12.8
BB-Saddle Position 77.5 - 79.5
Saddle-Handlebar 57.0 - 57.6
Saddle Setback 4.9 - 5.3
Seatpost Type NON-SETBACK

As you have already noticed, I need a frame with longer top tube. TST frames size 56 have rather short 56.5cm top tube but seat tube range is pretty close to what CC calculator's recommends(i.e Competitive Fit). Do you think TST 56cm frame is too small for me? I know Trek size 58 will be perfect for me but I really want to try this frame. I'm currently riding Marin Venezia with rough 54cmC-C frame with 570mm top tube + 120mm stem. My Venezia is pretty comfortable but I think my body is leaning towards the handlebar bit too much. What do you think?
 

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Discussion Starter · #2 ·
Btw....

How reliable is CC calculator?
 

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eminence grease
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You and I have virtually identical measurements.

The CC calculator worked fine for me with a couple of exceptions -

Saddle height was 1.5 to 3.0 CM to high for that inseam. I'll bet you you find yourself with a pretty extended leg if you set the saddle to 79.

Setback was 2+ cm too short

and you pretty much need a setback post to hit that setback number.

I look for two things when spec'ing a bike - a TT in the 56-58 range and a headtube between 15 and 16.5 cm. Everything else just works out. I know I could make that 56cm TST work for me and expect you can make it work for you.
 

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linus said:
How reliable is CC calculator?
I assume you mean the calculator on competitivecyclist.com. Of course there are variable from person to person but I found the Competitive Cyclist calculator to be somewhat close to my actual setup though I'm forced to use a much longer stem with stock frames to get the reach I need. I'm closest to the "The Eddy Fit".

Here are my numbers:

My measurments

Inseam: 79.5
Trunk: 65
Forearm: 35.5
Arm: 73
Thigh: 59
Lower Leg: 50.2
Sternal Notch: 143


My Fit

Seat tube range c-c: 53
Seat tube range c-t: 54.5
Top tube length: 54
Stem Length: 14
BB-Saddle Position: 70.3
Saddle-Handlebar: 55.9
Saddle Setback: 6.2
Seatpost Type: SETBACK


The Competitive Fit

Seat tube range c-c: 51.5 - 52.0
Seat tube range c-t: 53.1 - 53.6
Top tube length: 56.0 - 56.4
Stem Length: 11.7 - 12.3
BB-Saddle Position: 68.0 - 70.0
Saddle-Handlebar: 55.3 - 55.9
Saddle Setback: 5.5 - 5.9
Seatpost Type: SETBACK


The Eddy Fit

Seat tube range c-c: 52.7 - 53.2
Seat tube range c-t: 54.3 - 54.8
Top tube length: 56.0- 56.4
Stem Length: 10.6 - 11.2
BB-Saddle Position: 67.2 - 69.2
Saddle-Handlebar: 56.1 - 56.7
Saddle Setback: 6.7 - 7.1
Seatpost Type:SETBACK


The French Fit

Seat tube range c-c: 54.4 - 54.9
Seat tube range c-t: 56.0 - 56.5
Top tube length: 57.2 - 57.6
Stem Length: 10.8 - 11.4
BB-Saddle Position: 65.5 - 67.5
Saddle-Handlebar: 57.8 - 58.4
Saddle Setback: 6.2 - 6.6
Seatpost Type: SETBACK
 

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Discussion Starter · #6 ·
Thank you all of you for the feedbacks.....

but I still can't decide......:eek:

If 58 is better for me even though seat tube size will be bit too long, I probably let this one go. I wish I could hear from more people, but it seems to me that everybody is busy riding their bikes:D

wow.....buying a frame is harder than I thought:D
 

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missing info...

The saddle height is much too high, if your inseam was measured properly, to saddle like crotch contact in bare feet. If this is a pant's inseam, all your info from the fit calculator is wrong. With an 85cm cycling inseam, a typical saddle height would only be 74-76cm.

FWIW, your posted inseam is only 2cm more than mine, but you are more than 11cm taller. That would make you a bit short legged and long torsoed. Your lower leg length inseam is awfully long for your inseam. From floor to center of kneecap, my leg is 5cm shorter. Seems odd. It's also what's driving the amount of suggested saddle setback.

A lot of the decision on the proper vertical size of the frame should be based on an accurate saddle height, that's based on real riding experience and your desired saddle to handlebar height difference.

Normally, I'd say the 56cm frame would be the best choice. I suspect that the 58cm has a standover height around 83cm, which is only 2cm less than your inseam (IF it's a cycling inseam). I wouldn't ride a frame that large, but some folks do. Personally, I've always chosen c-t frames that were 28-30cm less than my cycling inseam and provided 4-6cm of standover clearance. I'm able to tolerate a handlebar height that's 8-10cm lower than my saddle. Riders who can't would most often chose a larger frame.
 

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Discussion Starter · #9 ·
C-40 said:
The saddle height is much too high, if your inseam was measured properly, to saddle like crotch contact in bare feet. If this is a pant's inseam, all your info from the fit calculator is wrong. With an 85cm cycling inseam, a typical saddle height would only be 74-76cm.

FWIW, your posted inseam is only 2cm more than mine, but you are more than 11cm taller. That would make you a bit short legged and long torsoed. Your lower leg length inseam is awfully long for your inseam. From floor to center of kneecap, my leg is 5cm shorter. Seems odd. It's also what's driving the amount of suggested saddle setback.

A lot of the decision on the proper vertical size of the frame should be based on an accurate saddle height, that's based on real riding experience and your desired saddle to handlebar height difference.

Normally, I'd say the 56cm frame would be the best choice. I suspect that the 58cm has a standover height around 83cm, which is only 2cm less than your inseam (IF it's a cycling inseam). I wouldn't ride a frame that large, but some folks do. Personally, I've always chosen c-t frames that were 28-30cm less than my cycling inseam and provided 4-6cm of standover clearance. I'm able to tolerate a handlebar height that's 8-10cm lower than my saddle. Riders who can't would most often chose a larger frame.
The measurements are not 100%, but I did measure them couple of times to be accurate as possible. Inseam could be 1 or 2 cm off but not more than that(my girl friend is too weak to simulate the saddle pressure). Am I short legged? My friend told me that the only thing that is odd about my body is the length of my arms(he said they are too long).

I've noticed that you don't mention much about top tube length. Do you think vertical measurements are much more important than top tube length? is 14.5cm head tube long enough for me? FYI, I like low handle bar height relative to my saddle. Thank you again
 

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Discussion Starter · #10 ·
terry b said:
Agreed across the board.
Since you said that you have virtually identical measurements, can you tell me your measurements and your bike sizes?
 

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no previous bikes??

A valid saddle height is the best guideline for vertical size. If that's not available, you can use any bike with a horizontal TT as an inseam measuring device. Block up the wheels, equally, until you get saddle-like crotch pressure, but not so much that it lifts your heels off the ground. I'll bet you're a couple of centimeters off (low) and that's a whole frame size. If you are, then the larger 58cm would probably be the better choice.

The reason it's so hard to comment on TT length is due to the many variables, like saddle fore/aft position, and arm length, in addition to torso length. Arm length measurements are typically not very accurate and every fit calculator measures different reference points. In this frame size, anything from a 110-140mm stem would be an acceptable length. Additional reach changes can be made with the handlebars. The 56 or 58 can undoubtedly be made to fit the same, but you should avoid a frame that has such a short head tube the it requires a lot of spacers and a high rise stem to get the bar height you need. Keep in mind that the headset adds 3cm to the HT length.
 

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eminence grease
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linus said:
Since you said that you have virtually identical measurements, can you tell me your measurements and your bike sizes?
I'm 5'11" and my cycling inseam is 85.09. So clearly we're close in porportion.

I'm not going to type them all in here - too much time. The CC calculator spit out numbers for me that are nearly the same as yours. I mentioned the results from the calculator that I think are bogus in my first answer to you.

I ride two 57cm and one 58 Colnagos. TTs on those bikes are 55.6 and 56.3 respectively.

I ride two custom bikes with 73 STA and 57 TTs.

I ride a Moots with a 73 STA and a 57 TT.

I ride another custom with a 74 STA and a 56 TT.

And I have a bunch more within these general ballpark numbers.

On each one my saddle height is 755mm, my saddle tip is 76mm behind the BB and the reach from the tip of the saddle to the center of the bar is 57cm +/- 5mm.

They all work.

Unless it was a very special deal, I would never consider a bike with a 58ST and 58TT.
 

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linus said:
The measurements are not 100%, but I did measure them couple of times to be accurate as possible. Inseam could be 1 or 2 cm off but not more than that(my girl friend is too weak to simulate the saddle pressure).
1 or 2 cm is quite a bit to be off by. You really should do your measurements at least three times and go by the averages.
 

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Discussion Starter · #14 ·
rocco said:
1 or 2 cm is quite a bit to be off by. You really should do your measurements at least three times and go by the averages.
Ya. The measurements are taken 5 times, but I still can't trust them.:eek:
 

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unless you are a cat 1 racer or speed freak

you will be happiest on a 58cm -- it is that simple
then you may change stem etc later
but a 56cm is too small for a guy your size for normal sport riding
 

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Discussion Starter · #16 ·
C-40 said:
A valid saddle height is the best guideline for vertical size. If that's not available, you can use any bike with a horizontal TT as an inseam measuring device. Block up the wheels, equally, until you get saddle-like crotch pressure, but not so much that it lifts your heels off the ground. I'll bet you're a couple of centimeters off (low) and that's a whole frame size. If you are, then the larger 58cm would probably be the better choice.

The reason it's so hard to comment on TT length is due to the many variables, like saddle fore/aft position, and arm length, in addition to torso length. Arm length measurements are typically not very accurate and every fit calculator measures different reference points. In this frame size, anything from a 110-140mm stem would be an acceptable length. Additional reach changes can be made with the handlebars. The 56 or 58 can undoubtedly be made to fit the same, but you should avoid a frame that has such a short head tube the it requires a lot of spacers and a high rise stem to get the bar height you need. Keep in mind that the headset adds 3cm to the HT length.
Problem is that my bike is not with me. I put my bike away for the winter and I'm away from home(I'm still a undergrad student). I think I made my decision to go with this frame. Let me know if you have more concerns.

Thank you very much
 

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Discussion Starter · #18 ·
collectorvelo said:
you will be happiest on a 58cm -- it is that simple
then you may change stem etc later
but a 56cm is too small for a guy your size for normal sport riding
Oh. Do you think so? Why? Because of top tube length? or seat tube length? Let me know. :)
 

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eminence grease
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collectorvelo said:
you will be happiest on a 58cm -- it is that simple
then you may change stem etc later
but a 56cm is too small for a guy your size for normal sport riding
Finally, I understand why I am so unhappy. I guess I'll replace everything I have with 58s.

The funny thing is, I own four custom bikes and I was fit/measured by four different builders. So, my numbers match the OP's numbers and four builders put me on bikes with 56-57TTs. Yet, you seem convinced the OP will be happier on a 58. Why is that?
 

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Discussion Starter · #20 ·
DOUGLAS Precision

I'm thinking more towards DOUGLAS Precision frame that Colorado Cyclist sells. I have no idea how they measure their frame size, but if they do measure them like TST, 57 might be perfect for me. And 1-1/8" Headtube is another plus.:)

Does anybody have the DOUGLAS Precision geometry chart?
 
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