# Explain Colnago sizing for me??



## FTR (Sep 20, 2006)

I am looking around for a nice used Colnago frame but am a little hesitant as I keep reading that Colnago sizing is different to other manufacturers.
Can anyone explain what it is that is different??
Can anyone give me an idea as to what size would be best for me??
Details as input to Competitive cyclist's fitting program:

Inseam: 86.5
Trunk: 68
Forearm: 35
Arm: 64
Thigh: 63
Lower Leg: 59.5
Sternal Notch: 155
Total Body Height: 190

I am currently riding a 58cm Specialized Allez Comp which is a sloping TT and feels fine (if not a little stretched out), if that helps.
Also if anyone can point me in the direction of a Master Olympic or similar would be awesome.


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## wasfast (Feb 3, 2004)

Ignore the "size" and verify dimensions of the same type between manufacturers. The size on Colnago's is center to top which is misleading because they have a fair bit of extension of the seat tube above the top tube. When you look at center to center of the seat and top tubes, their geometry isn't much different than any other manufacturer.

If you are willing to spend the sort of money that Colnago is, having a fitting on a fit bike to see how it will actually feel is highly recommended. Guessing on a $4k frame is nuts compared to the $100-$150 it would cost for a fitting.


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## FTR (Sep 20, 2006)

OK that seems simple.
I always look at TT and ST measurements when I am looking at bikes so this is really no different. 58cm frames seem to fit quite well.
I will be looking for a nice older frame like the Master Olympic so there is little chance of getting a fitting for it. Most likely I will have to buy off ebay and will perhaps have to buy from Europe or the US (I am in Australia).


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## C-40 (Feb 4, 2004)

*short legs...*

An 86.5cm inseam is pretty short for your height. Do you have an actual saddle height from the center of the BB to the top of the saddle, along the center of the seat tube, that you can post?

You say that your current frame feels streteched out, but with what length stem? Without the stem length, that doesn't help much. A stem angle and the amount of spacer under the stem or a handlebar height from the floor to the top of the bars would tell a lot about the vertical size of frame you need.

Based solely on your (short) inseam, a 58cm Colnago would be the correct vertical size. It would have have a lot shorter HT and TT than your current frame. With a 30mm headset, the HT would be 195mm, which is about 25mm less than your current frame (assuming a 15mm top section with the 205mm HT). The TT length would require a 20mm longer stem to produce the same reach.

You may want to consider one of the sloping sizes, which have longer TTs and HTs, but more standover clearance. The 57cm sloping would have the same reach as you current frame and 18mm more HT length than the 58cm conventional frame.

The Colnago geometry chart is probably the most complete of any you'll find. It clearly lists the c-c frame size, and the c-t frame size. At the website linked, click on the characteristic tab to get the geometry drwwaing and chart.

http://www.colnago.com/en/catalogo2007/index.php


http://www.specialized.com/bc/SBCGeometryPopup.jsp?spid=21894


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## FTR (Sep 20, 2006)

C-40 said:


> An 86.5cm inseam is pretty short for your height. Do you have an actual saddle height from the center of the BB to the top of the saddle, along the center of the seat tube, that you can post?


82cm (32.3")



C-40 said:


> You say that your current frame feels streteched out, but with what length stem? Without the stem length, that doesn't help much. A stem angle and the amount of spacer under the stem or a handlebar height from the floor to the top of the bars would tell a lot about the vertical size of frame you need.


Stem length is 130mm which I feel is too long but have not gotten around to swapping out yet. Floor to bar height is 98cm (38.5")



C-40 said:


> You may want to consider one of the sloping sizes, which have longer TTs and HTs, but more standover clearance. The 57cm sloping would have the same reach as you current frame and 18mm more HT length than the 58cm conventional frame.


Sloping TT = Blech!!! :cryin:  
I already have a sloping TT on my Specialized and am wanting to move back to something more traditional in shape.
For some reason I cannot access the Specialized website to check the geometry chart for my bike but my measurements are that it has a 57cm TT and a 54 cm ST.



C-40 said:


> The Colnago geometry chart is probably the most complete of any you'll find. It clearly lists the c-c frame size, and the c-t frame size. At the website linked, click on the characteristic tab to get the geometry drwwaing and chart.


While knowing that the Competitive Cyclist fitting software is not going to replace a proper fitting its recommendations were:

Seat tube range c-c: 56.0 - 56.5
Seat tube range c-t: 57.8 - 58.3
Top tube length: 55.8 - 56.2 

This seems pretty much inline with the Colnago 58cm traditional geometry and may explain to some extent why I feel stretched out on my current bike.


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## C-40 (Feb 4, 2004)

*new advice...*

If your saddle height is 82cm, that's a lot more common for your height, but would also be more common for a person with a cycling inseam around 92cm, not 86.5. I'll assume the saddle height is accurate. In that case, the fit calculator is giving you the wrong result. It probably also suggested a saddle height of only about 77cm, not the 82cm you've posted. Cycling inseam is measured to saddle-like crotch contact in bare feet. You didn't put in your pants inseam by mistake?

To get the bars up to a 98cm height, you would need a total head tube length (with spacers and headset) of about 260mm, using an 84 degree stem. The HT on a 58cm Colnago won't go over 225mm, so this size is not even close to being large enough. Even a flipped 96 degree stem would only make up about 20mm of the 35mm shortage.

You probably need a 61 or 62cm, which have about the same reach as your current frame. Even then, the HTL of 185mm will only increase to 245mm with the headset and 30mm of spacers. A 96 degree stem angle would still be required.

FYI, the listed dimensions on your specialized are 73 degree STA, 58.2cm TT and 205mm head tube. The tall HT seems to indicate that this frame is a "comfort" style, not a racing frame. The fact that you can tolerate a 130mm stem says the TT is not too long.


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## FTR (Sep 20, 2006)

Full details of CC's recommendations:

The Competitive Fit (cm)
-------------------------------------------
Seat tube range c-c: 56.0 - 56.5
Seat tube range c-t: 57.8 - 58.3
Top tube length: 55.8 - 56.2 
Stem Length: 11.5 - 12.1
BB-Saddle Position: 80.0 - 82.0
Saddle-Handlebar: 54.4 - 55.0
Saddle Setback: 5.0 - 5.4
Seatpost Type: NON-SETBACK

I reckon that the stem on my Specialized could be at least 10mm shorter as my most comfortable position on the bars is about 10mm back from the brake levers.
The bar position has been manipulated to this height in an attempt to get the bars back closer to my saddle. I have also used a straight Thomson seatpost for this purpose. This is better but I still think that a shorter stem is needed.


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## C-40 (Feb 4, 2004)

*seatpost...*

I think the info from CC is wacky. I'd stongly recommend rechecking your cycling inseam. A proper sadle height should be very close to 10cm less than your cycling inseam, not 4-6cm. The frame size they are recommending would have a HT so short, you could never get the bars up to the height you have now.

Have you ever checked your knee to pedal relationship with a plumb bob? A non-setback post should not be used to get the saddle closer to the handlebars. It's purpose is to position the knee relative to the pedal.

www.coloradocyclist.com/bikefit

One good way to measure cycling inseam is to use a bike with a horizontal TT as the measuring tool. Block up the wheels equally, until the TT places saddle-like pressure in the crotch. Then measure from the floor to the top of the TT.


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## FTR (Sep 20, 2006)

OK. Finally got back to this.
Re-checked my inseam by placing a spirit level between my legs snugly into my groin and with one end of it against a wall.
I then marked the position of the top edge of this level on the wall and measured this position from the floor.
I was wearing my cycling shoes and came up with a height of 90.5cm.
Measurement in bare feet is 88.5cm.

I find my position to be too far behind the pedal spindle with the lay back seatpost and feel much stronger with my pedal stroke using a straight seatpost.


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## C-40 (Feb 4, 2004)

*more...*

The 61cm Colnago should have a standover height of about 85cm, so you will have adequate standover clearance and about the same reach as your current frame. The HT length would only be 243mm with the headset and 30mm of spacers. If you must have the bars up that high, then a 96 degree stem will be required.


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## FTR (Sep 20, 2006)

C-40 said:


> The 61cm Colnago should have a standover height of about 85cm, so you will have adequate standover clearance and about the same reach as your current frame. The HT length would only be 243mm with the headset and 30mm of spacers. If you must have the bars up that high, then a 96 degree stem will be required.


Sounds like I got lucky then when I bought a 58 x 61cm frame yesterday then.  

http://forums.roadbikereview.com/showthread.php?t=87875


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## C-40 (Feb 4, 2004)

*hopefully...*



FTR said:


> Sounds like I got lucky then when I bought a 58 x 61cm frame yesterday then.
> 
> http://forums.roadbikereview.com/showthread.php?t=87875


It was a 61cm frame with a 58cm TT. You should be able to get it to fit since it requires a quill stem.


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## FTR (Sep 20, 2006)

C-40 said:


> It was a 61cm frame with a 58cm TT. You should be able to get it to fit since it requires a quill stem.


Measurements I was given were 58cm TT and 59cm ST but both measurements were C-C so I am assuming that the ST would be 61cm C-T as per the Colnago website for their traditional non-sloping frames.


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