's Forum Archives - General

Archive Home >> General(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 )

colnago sizing (paging c-40)(11 posts)

colnago sizing (paging c-40)zippi
Nov 30, 2003 7:24 AM
are colnago's measured c-t or c-c? i'm almost certain they're c-t. i need a 55 c-t. why does the "55" at my lbs have a 15cm. headtube. if i order one, what do i need to ask for?
read the charts???C-40
Nov 30, 2003 8:04 AM
The geometry is published with both c-t and c-c dimensions. The c-t dimension is used to determine the frame size. If the 55cm frame at your LBS has a 150cm headtube (without headset), it's a 56cm, not a 55. This can be easily verified by measuring the frame c-c. A 55cm will measure 53cm c-c and a 56 will measure 54cm c-c.

The site above has the current geometry. The P dimension is the frame size, the O dimension the TT length and the Pcc diemension is the c-c frame size.
read the charts???zippi
Nov 30, 2003 2:11 PM
i read the charts, but trialtir and competativecyclist have different charts. according to competative cyclist a frame with a 150cm hd is a 57. i'll go to the lbs tomorrow and measure it. thanks for your time
charts???Rusty Coggs
Nov 30, 2003 2:56 PM
Add more confusion and go look at the chart at They all get the TT length right, but for a 58 like mine the numbers are 159 from colnago,and 159 from competitive but 165 from wrenchscience. Actual measurement on my two 58s is 153 and 156....Colnago measures C-T, and sometimes the top is an extended seaattube. check TT length, as a double check
Nov 30, 2003 4:06 PM
a 55 has 54.3 and a 54 has a 54 top tube. i wouldn't be sure even with a tape measure.
head tube size is the most acurate measure.
charts???Rusty Coggs
Nov 30, 2003 5:02 PM
The charts have changed !!!!C-40
Nov 30, 2003 5:17 PM
I've owned both a 55 and a 54cm. The current charts show different HT lengths than the charts that were on the site until the recent change.

My 2002 model C-40 in a 54cm has a 125mm head tube. The new charts show a 132mm head tube. It's possible that they have increased the HT lengths across the board, for 2004.

You might want to check the Colnago website, although it's never had a geometry chart before.
Nov 30, 2003 5:28 PM
As far as I can tell, the only thing that's changed on the charts is the head tube length. The rest remains the same, so if a 55cm c-t frame is needed, that's what you should order, a 55cm frame. Apparently, the HT length may be a bit longer if yu get a 2004 model, but otherwise the dimensions are unchanged.
What about headtube angle?DY
Nov 30, 2003 10:39 PM
Where is that listed? I looks like the charts at Trialtir shows everything but HT angle.
Dec 1, 2003 3:22 AM
132 is exactly what a 55 had before.. waht if there's a misprint on the website. i would have nightmares if i was ordering a c50 sight unseen.
no nightmares...C-40
Dec 1, 2003 6:04 AM
If you look closely, the listed HT length is 7mm greater across the board, compared to last year. A 55cm frame is listed as having a 141mm HT instead of a 134mm. If ordering a frame, it would be wise to contact Trialtir and get confirmation of this change. Other than that, you should be able to order the same size as previous years.