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jaimemmm

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I CURRENTLY HAVE A 54CM MERLIN CYRENE. IT FITS ME PERFECT. I AM THINKING OF BUYING A COLNAGO C-40 , 54 CM. I KNOW THAT THE C-40 HAS A HIGH BOTTOM BRACKET. WILL A TRADITIONAL SIZE 54CM. C-40 HP FIT ME OR DO I NEED A SMALLER SIZE. I AM 5'8 AND HAVE A INSEAM OF 30'. :arf: :arf: THANKS
 
Discussion starter · #5 ·
my cyrene is a bought new 2002 cyrene . I know they they don't build a 54 now but they did then. awesome looking measurements . the head tube length is also very nice considering most 53 tubes look very short. a 55 is way to big for me. ahhh, the days when merlin sold a 54.
 
No!

That's the worst bunch of BS ever written. Colnagos are fit to the rider like any other bike.

About the only difference is the steering geometry. They have a relatively slack head tube angle that increased the front-center and wheelbase.
 
info...

Just off hand, I'd say that the 54cm is OK for your torso length, but large for your leg length.

If you want an accurate answer, you'd need to post the TT length, seat tube angle and head tube length of the Merlin. If the Merlin uses a conventional press fit headset, the head tubes can be compared directly.

I owned a 54cm. If fit me quite well, but I have an 83cm cycling inseam with a 73cm saddle height. If you saddle is a lot lower, then you won't have a lot of seatpost showing.
 
according to the links I posted you need one cm smaller than the size you usually ride, and lower handlebars and a longer stem.

I have made the experience, I do have riden several Colnagos and currently I have 3 ( EP, ExtremeC and C40) and I have experienced the bigger-higher-shorter vs smaller-lower-longer combinations and I can say their advice is spot on.

C-40 doesn't seem to agree. I would be interested in knowing on what bases his opinion.
 
sorry...

My comments were directed toward the bike sport michigan article. It is baloney.

You fit a bike based on the contact points that it will provide. You need to have the correct head tube length and the proper reach. The actual frame size number means nothing.

I've owned two C-40 frames and found no reason to buy a smaller size than I'd ridden before.

As an example, a 52cm model C-40 would have nearly identical dimensions to a current LOOK 585 in a 51cm size. You could buy a 54cm and get an 18mm taller head tube, but the reach only increases by about 5mm.
 
no

Your fit is not determined by the bike. Handlebars height should meet the rider's needs. The same goes for reach, it should meet the rider's needs and the reach on Colnago frames is not particularly short, requiring a longer stem.
 
Although I like a more traditional fitting than C-40 (less drop from seat to bar) 'cause I'm old skool, I have noticed no particular difference between 'nagos and any other bike

*except*

Colnagos (like a lot of Italian bikes) market their traditional geometry bikes measured c-t-t, unlike the c-t-c of a lot of other manufacturers. It seems I have to argue this point or ask for clarification from every eBay seller out there. For argument's sake a 59cm Colnago (stamped on the BB usually) with traditional tubing/geometry is about a 57 square measured c-t-c. This was true of my 2002 CT-1 that I sold just recently

Also, In the '80s they started using a Freuler style geometry for large frame sizes, extending the seat and head tubes above the top tube. So later Masters/Tecnos with have a 58.5 c-t-c toptube/57 c-t-c seat tube, with ht/st extensions to give you a 60 cm and up nominal size as marked on the BB.

Apart from that, I find little difference in fit--I'm currently riding a Simonetti--derivative Italian (Masi>>Wizard>>Medici>>Simonetti) and a marked "59" is within a mm of the geometry of the "59" CT-1...
 
I have to agree with C-40 on this. There's this school of "geometry experts" out there who will tell you that Colnagos have this wierd geometry that won't fit most people or correspond to most bikes. Over the last 10 years, I've owned a Litespeed Ultimate, Colnago C-40 and Kestrel 200 Sci. All of them were 56 cm bikes, with the same 44 cm bars, 11 cm stems, same saddles and pedals, same components. They all fit me just fine. The bikes ride differently. Hard to say whether one was markedly better, just a bit different.

Within reason, most of the fine fit adjustments on a bike are made with stem length, saddle height and saddle position. I'm not saying that someone riding a 60 cm bike frame can comfortably fit a 50 cm frame, but a 55 cm frame versus a 54 cm frame isn't all that different (about 1/3 of an inch). If your Merlin is 54 cm and you're happy with it, get the 54 cm Colnago.
 
have you all read the redkite blog article ? doesn't it make any sense ?
 
C-40 said:
That's the worst bunch of BS ever written. Colnagos are fit to the rider like any other bike.

About the only difference is the steering geometry. They have a relatively slack head tube angle that increased the front-center and wheelbase.
Did you read the first article?

The point does not seem to be that your body position is different, as you seem to be implying. The point is that Colnago intends riders to ride a smallish frame with long stem and large setback and they tailor the steering and seat angles to match that intent. Why else would you have a 75 degree seat angle on a road bike?????

I can personally attest to having ridden bikes that "fit" my body, but felt weird because I had to use a long stem to get my position. Colnago appears to have the opposite problem - if you get it sized a little large the steering feels weird because the stem is on the short side.

I don't know if that's true or not (since Colnago doesn't publish steering angles), but C-40 seems to be arguing about something different than the article is explaining, namely: Create your usual position on a size smaller frame.

It would be nice if Colnago put out something about their sizing philosophy so we didn't have only second hand articles about it, and the lack of steering data makes it hard to think out on your own. But the super steep seat angle definitely points to something strange going on. Example:

Let's say you buy your usual correct size frame, based on TT length. The first thing you'll do to fit it is move the seat aft close to 2cm more than some other frame. So you're 53 top tube is now effectively 55cm. You counter this by using a stem that is 2cm shorter than your previous bike, which has an effect on your steering. Depending on the steering angle, this may do two things - make the steering twitchy, and shift more weight off the front wheel and to the rear wheel, which will also make it twitchy.

Moving a size down will give you back an effective TT that is more normal. I would bet that part of the "trick" in sizing Colnagos is adding to the TT what the steep seat angle takes away.

Anyway, this all sounds like a boondoggle. Unless I was dealing with some sort of Colnago expert (and neither posted article sounded like they were written with all that much experience) I'd avoid trying to out-guess their weird geometry. There's plenty of fish in the sea, and most don't make a secret of fit or geometry.
 
Salsa_Lover said:
have you all read the redkite blog article ? doesn't it make any sense ?
I really didn't find the Redkite article very illuminating. All this analysis seems to be about BB drop, and admits he doesn't know what's going on with the steering. He also doesn't address how the steep seat angle longer drop are going to affect wheelbase and weight distribution.
 
The Redkite article makes more sense than the Michigan sports article, but it is directed at trouble shooting people who are experiencing squirrely handling, and Padraig's description of what might be causing the problem is thoughtful and thought-provoking.

I'd love to have a few EP's and a range of stems to try out various combinations to see if chages are noticeable...

For the bikes in the middle of the range with a 73 deg STA, the issue is likely a non-starter; the 43 deg fork (and resulting trail) seems to me to be fairly typical.

And Padraig's general description of the fitting process is the same as C-40's in other threads--start with the TT length....
 
paredown said:
The Redkite article makes more sense than the Michigan sports article, but it is directed at trouble shooting people who are experiencing squirrely handling, and Padraig's description of what might be causing the problem is thoughtful and thought-provoking.

I'd love to have a few EP's and a range of stems to try out various combinations to see if chages are noticeable...

For the bikes in the middle of the range with a 73 deg STA, the issue is likely a non-starter; the 43 deg fork (and resulting trail) seems to me to be fairly typical. 43mm of rake is typical for a typical 73 head angle. We don't know what the head angle of the Colnago is, and the first article is implying that it is not typical.

And Padraig's general description of the fitting process is the same as C-40's in other threads--start with the TT length....
The redkite article says:
But is it squirrelly? Based on what I see on paper, my gut says it’s great on fast descents. For anyone not already accustomed to Italian bikes, out of the saddle, this bike is a bit more maneuverable than might be comfortable. I could see how someone might drift off their line on their first few out-of-the-saddle sprints.
So here he seems to be disagreeing that the geo looks at all squirrelly. He goes on to say this:
I’d expect this bike to seem rather maneuverable out-of-the-saddle, but great on descents, unless, of course, it had a short stem and a high handlebar, and then it would seem squirrelly all day, every day.
Here he's referring to the same problem I am, but hasn't connected it with the fact that if you start with TT length without reference to seat angle, you ARE going to end up with the short stem that he glosses over as an unlikely scenerio.

I guess I was just left hanging by a scholarly analysis of geometry that makes assumptions about head angles and trail, then minimizes their effect, while dismissing the claims of professional reviewers from a magazine thought to rubberstamp all their reviews. The other article at least acknowledges that Colnago geometry is not typical and suggests reasons why and how to address them.

I would be not at all surprised if the Colnago uses a fairly steep head tube angle with a resulting low trail because of the medium rack fork. This was a popular set up for racing in crummy conditions in Europe, because low trail is more stable at lower speeds. But they are vague on descents. A longer stem may help that lack of feel and stability, which takes us back to the first article.
 
also no....

rx-79g said:
Let's say you buy your usual correct size frame, based on TT length. The first thing you'll do to fit it is move the seat aft close to 2cm more than some other frame. So you're 53 top tube is now effectively 55cm. You counter this by using a stem that is 2cm shorter than your previous bike, which has an effect on your steering. Depending on the steering angle, this may do two things - make the steering twitchy, and shift more weight off the front wheel and to the rear wheel, which will also make it twitchy.

Moving a size down will give you back an effective TT that is more normal. I would bet that part of the "trick" in sizing Colnagos is adding to the TT what the steep seat angle takes away.

Anyway, this all sounds like a boondoggle. Unless I was dealing with some sort of Colnago expert (and neither posted article sounded like they were written with all that much experience) I'd avoid trying to out-guess their weird geometry. There's plenty of fish in the sea, and most don't make a secret of fit or geometry.
You analysis is not correct. You don't typically have to move the saddle back 2cm and use a shorter stem. If you really think so, then give me a frame example for a proper comparison.

There is nothing weird about the geometry. As I noted, the TT length and STA are both about the same as typical LOOK 585, in the size I ride.

The big difference is seen in the steering geometry. The HTA is more slack and the F-C is longer. The slack HTA creates a little more steering trail and a little slower steering. For a given rider position, the weight on the front will be a little less.

The geometry makes for totally stable descending, but if you're used to a frame with faster steering, it requires a little more rider input.
 
I have been on a 56 traditional almost since I started riding some 10 years ago on a 11cm stem.

I have riden Colnagos on sizes 57,56,55 and 52s.

I find myself the best on the 56 traditional or 52s ( same virtual dimensions ) on a 12cm stem.

My EP is a 52s, this was my first Colnago. I bought it from a guy with very similar measurements as me, only he is fatter and older. He bought the bike for the looks and set it up with a high handlebars and short stem.

He sold it because he dindn't like the way the bike rode and felt. he sold it to buy an Specialized Roubaix ( if that is a hint )

At that time I was riding a Bianchi 928SL in size 57 that has same virtual dimensions as a 56 traditional on a 11cm stem.

I tried the EP as it was setup and also didn't like it nor found an improvement compared to the Bianchi.

Then I started looking for other Colnagos and tried one in 57 with a 11cm stem with low handlebars and it was good.

Finally I bought my Extreme C on a 56 Freuler ( the frame is like a 54 with a longer head tube ) this Extreme C had the steerer tube cut very short and handlebars are very low, it has a 11cm stem ( Cinelli Ram ) but the TT is 55 cm.

I had put for sale the EP 52s and bought a C-40 in size 55 this one has a 54.5cm TT, the EP 52s has a 55cm virtual TT.

well, I set up the C-40 as close as possible to the Extreme C and experimented with 11, 12 and 13mm stem and high and low handlebars. The bike felt, rode, climbed and descended beautifully, probably the best would be to find a 12.5cm stem though.

So then I went back to the EP, set the bars as low as it was possible and a 12cm stem. ( I think I could go to 13cm and it would be better but helas my handlebars are also Cinelli Rams, maybe i would look for another Cinelli RAM in 12 for the Extreme C )

Now the EP was a completely different bike. The handling, feel and ride is much much better than what it was before with the handlebars 2cm higher and 2cm shorter stem.

Needless to say, my Bianchi 928SL feels and handles "big" now, not as agile on and off the saddle as the Colnagos, It is now for sale.

keep in mind the Colnagos head tubes are longer due to the non-integrated headset.

So, I am no expert, but I find those 2 articles I posted make a lot of sense.
 
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