"Pinched" Tubing?
#1
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"Pinched" Tubing?
Anybody know anything about this?
Does it compromise the integrity (i guess i mean strength) of the frame?
Does it compromise the integrity (i guess i mean strength) of the frame?
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it's supposed to be like that, (i think colnago may have done it first).
supposedly it makes the tubing stiffer.
supposedly it makes the tubing stiffer.
#3
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but does it work, or is this another example of fashion-over-function bikebuilding (like drilling holes in every part to make the bike lighter, whatever that's called)?
the only pictures i have are taken by the seller on ebay. how does this kind of frame look in real life?
the only pictures i have are taken by the seller on ebay. how does this kind of frame look in real life?
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I have a friend with a frame EXACTLY like that (forgot the maker)
The way I see it, I would think that those dimples act as stress concentrators. Anything not round would concentrate stress on some axis.
But I wouldn't worry about it - ride it 'till it dies.
The way I see it, I would think that those dimples act as stress concentrators. Anything not round would concentrate stress on some axis.
But I wouldn't worry about it - ride it 'till it dies.
#6
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i'm glad there are a few of you on here on a sunday afternoon.
holler for working on the weekend.
holler for working on the weekend.
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They used to do that golf shafts in the old days to stiffen them. They called it "fluting."
I don't think the transitions in those tubes are sharp enough to create problems for the frame.
I don't think the transitions in those tubes are sharp enough to create problems for the frame.
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Originally Posted by gh-ap
but does it work, or is this another example of fashion-over-function bikebuilding (like drilling holes in every part to make the bike lighter, whatever that's called)?
the only pictures i have are taken by the seller on ebay. how does this kind of frame look in real life?
the only pictures i have are taken by the seller on ebay. how does this kind of frame look in real life?
('drillium' is one way that drilled-out components are described. drillium is a mythical element that's lighter than anything else available).
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i found another frame that's not as weird.
please, sannino, be mine.
please, sannino, be mine.
#16
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This is a type of tubing called 'dented inium'. This is far stronger than any other tubing known to man, 'though women know of far stronger tubing'. I would recomend buying this frame and beating your chest on the highest hilltops, proclaiming your tubeset to be far superior to all others.
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classic design, yes. more classic than a classic sannino? no.
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Originally Posted by absntr
Fixedfiend, calling fixedfiend and his Colnago...
It's Columbus exclusive Gilco Design tubing for Colnago. This is the supposed story of how it came about:
It is known; however, that the current trademark Gilco tubing used by Colnago, in which the main tubes are sort of diamond-shaped instead of round resulted from Merckx's opinion that Colnago's frames did not descend well. Comparing them to DeRosa's, Merckx felt the Colnago to be too flexible.
Upon hearing this, Ernesto set about remedying the problem, even though it was the only complaint he had heard regarding his frames' performance.
But if Eddy Merckx feels your bike is too flexible, you should heed the advice and make changes. Colnago did not want to add weight to the bike design he had worked hard to lighten, so he decided to increase the torsional rigidity without adding weight.
With some work using an ordinary shop mandrel on normal round tubes, he flattened all four sides of the tubes to decrease flexibility under pedalling forces, and unknowingly produced his future trademark.
For many years now, Columbus has drawn the diamond-shaped tubes to Colnago's specification, and two decades of racing have proven the merits of the idea. The resulting frame is light, stiff and offers a compliant ride quality, all of the attributes of a great race bike.
In my honest opinion of riding this bike for the last month, I have to say that this is the sickest ride.
Torsional stiffness yet super plush and compliant. It's all true. F.F.
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Originally Posted by gh-ap
Anybody know anything about this?
Does it compromise the integrity (i guess i mean strength) of the frame?
Does it compromise the integrity (i guess i mean strength) of the frame?
No Yes Colonago was the one of the first, Rossin also did frames like that too.
S/F,
CEYA!
#21
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Geez, another forum member that sounds like they write advertising copy for a living. Nice work Fixedfiend!
Most tubes in a bike frame experience out of plane bending. Best shape for that? Round tubing. Best shape for in-plane bending? Oval.
Best shape for bending of consumer consciousness? Star, diamond, fluted, crimped, cramped, clamped, dimpled, hydroformed......
Most tubes in a bike frame experience out of plane bending. Best shape for that? Round tubing. Best shape for in-plane bending? Oval.
Best shape for bending of consumer consciousness? Star, diamond, fluted, crimped, cramped, clamped, dimpled, hydroformed......
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Originally Posted by Thylacine
Geez, another forum member that sounds like they write advertising copy for a living. Nice work Fixedfiend!
Most tubes in a bike frame experience out of plane bending. Best shape for that? Round tubing. Best shape for in-plane bending? Oval.
Best shape for bending of consumer consciousness? Star, diamond, fluted, crimped, cramped, clamped, dimpled, hydroformed......
Most tubes in a bike frame experience out of plane bending. Best shape for that? Round tubing. Best shape for in-plane bending? Oval.
Best shape for bending of consumer consciousness? Star, diamond, fluted, crimped, cramped, clamped, dimpled, hydroformed......
Oh, by the way, if you need me to overhaul your site with some decent copy, let me know, cause that $hit is Wack! Pretty corny too.
Last edited by fixedfiend; 05-15-05 at 11:05 PM.
#23
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Originally Posted by fixedfiend
That was taken from a cycling history website. Oh yes, you must be right. The greatest bicycle frame maker in history has duped us all into thinking his bicycles are just marketing hype. How stupid of us consumers and the world champions who have ridden his bicycles. Only those who can experience will believe anyway.
Oh, by the way, if you need me to overhaul your site with some decent copy, let me know, cause that $hit is Wack! Pretty corny too.
Oh, by the way, if you need me to overhaul your site with some decent copy, let me know, cause that $hit is Wack! Pretty corny too.
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Originally Posted by fixedfiend
That was taken from a cycling history website. Oh yes, you must be right. The greatest bicycle frame maker in history has duped us all into thinking his bicycles are just marketing hype. How stupid of us consumers and the world champions who have ridden his bicycles. Only those who can experience will believe anyway.
Oh, by the way, if you need me to overhaul your site with some decent copy, let me know, cause that $hit is Wack! Pretty corny too.
Oh, by the way, if you need me to overhaul your site with some decent copy, let me know, cause that $hit is Wack! Pretty corny too.
#25
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actually, the "brothas" I know say corny all the time when describing ****