Frame Kink?
#1
Thread Starter
Senior Member
Joined: May 2005
Posts: 216
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From: SE Pennsylvania
Bikes: Vintage French road bikes, older "rescue" mountain bikes
Frame Kink?
Hope the attached picture shows this. I got this bike used when I was in Junior High, and have ridden it for many miles ever since. I am 51 years old now, so have had it for almost 40 years. I just recently noticed that it has a kink in the down tube where it meets the head tube. I think it has had this defect ever since I have owned the bike, but I'm not sure. A couple of questions:
1) What type of impact would have caused this "kink"? I assume that that the fork and wheel would have been bent as well, so they couldn't be the present ones? What I am getting at is was this the result of an accident before I owned the bike, and the fork and wheel were replaced, or could this have been the result of careless movers since then? Could the frame have been bent like this, but not the fork or wheel? I can't think of any way this could have happened without "collateral damage", but I'm willing to listen to opinions.
2) Would this kink affect the way the bike rides or its safety?
1) What type of impact would have caused this "kink"? I assume that that the fork and wheel would have been bent as well, so they couldn't be the present ones? What I am getting at is was this the result of an accident before I owned the bike, and the fork and wheel were replaced, or could this have been the result of careless movers since then? Could the frame have been bent like this, but not the fork or wheel? I can't think of any way this could have happened without "collateral damage", but I'm willing to listen to opinions.
2) Would this kink affect the way the bike rides or its safety?
#2
juneeaa memba!


Joined: Oct 2003
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From: boogled up in...Idaho!
Bikes: Crap. The box is not big enough...
I have kinked a few bikes...the cause is a frontal impact. The top tube probably shows some subtle deformation as well. If the fork is stronger than the frame the frame is kinked in this fashion. Nothing is compromised, really, if no cracks are present. The handling is different than it was before the frame was tweaked, but if the head on was head on, the symmetry of the frame may not even be compromised.
If you've owned it for 40 years...what the heck is it? We need some more pictures...of course. Easthill, you're welcome.
If you've owned it for 40 years...what the heck is it? We need some more pictures...of course. Easthill, you're welcome.
#3
www.theheadbadge.com



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From: Southern Florida
Bikes: https://www.theheadbadge.com
#4
feros ferio

Joined: Jul 2000
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From: www.ci.encinitas.ca.us
Bikes: 1959 Capo Modell Campagnolo; 1960 Capo Sieger (2); 1962 Carlton Franco Suisse; 1970 Peugeot UO-8; 1982 Bianchi Campione d'Italia; 1988 Schwinn Project KOM-10;
With a frontal impact, such as riding into a wall (or an errant motor vehicle -- been there, done that, not recommended), the frame will generally bend before the wheel or the fork will. The damage will start at the bottom of the front of the downtube, as on your frame, manifesting itself on the bottom of the front of the top tube as well, in the event of a more severe collision.
I kinked my first Capo's top tube and downtube at the end of the butting when a motorist left-crossed me. I had the frame cold-set straightened at Rancho Park Cycles in West Los Angeles and got 6 more years out of it before the downtube began to rupture where it had been bent. MY safety was never compromised, and I was able to ride home very gingerly with a cracking downtube, but it was a little embarrassing to let some kid on a Varsity beat me up a 12% grade as I watched the crack form and propagate from the bottom of my downtube.
I kinked my first Capo's top tube and downtube at the end of the butting when a motorist left-crossed me. I had the frame cold-set straightened at Rancho Park Cycles in West Los Angeles and got 6 more years out of it before the downtube began to rupture where it had been bent. MY safety was never compromised, and I was able to ride home very gingerly with a cracking downtube, but it was a little embarrassing to let some kid on a Varsity beat me up a 12% grade as I watched the crack form and propagate from the bottom of my downtube.
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"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069
"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069
#5
Lanky Lass
Joined: Sep 2005
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From: Take a deep breath, and ask--What would Sheldon do?
Bikes: Nishiki Nut! International, Pro, Olympic 12, Sport mixte, and others too numerous to mention.
East Hill
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TRY EMPATHY & HAVE LOVE IN YOUR HEART, PERHAPS I'LL SEE YOU ON THE ROAD...
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TRY EMPATHY & HAVE LOVE IN YOUR HEART, PERHAPS I'LL SEE YOU ON THE ROAD...
#6
Senior Member
Joined: Jun 2007
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From: A Coffin Called Earth. or Toronto, ON
Bikes: Bianchi, Miyata, Dahon, Rossin
if you've loved it for 40 years, and can't stand the idea of riding with the kink because of safety, then I would suggest you decorate your living room with it. Most people aren't even married that long. add a little kink to your room.
Maybe you might even strip it down first to restore it to show room quality.
Maybe you might even strip it down first to restore it to show room quality.
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Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
https://sanfrancisco.ibtimes.com/arti...ger-photos.htm
Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
https://sanfrancisco.ibtimes.com/arti...ger-photos.htm
#7
Thread Starter
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Joined: May 2005
Posts: 216
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From: SE Pennsylvania
Bikes: Vintage French road bikes, older "rescue" mountain bikes
Pictures and story are here: https://www.geocities.com/fritz125541/Jaubert I had quite a time getting the original picture shown above below 100 meg so that I could post it. It doesn't show the frame kink all that well, but that may be the best I can do. There are no cracks or other indications of damage - all you're seeing is dirt and light reflections. What I am mostly trying to find out is whether this damage is from a crash probably before I owned the bike, or whether it could be from careless handling by movers. I am pretty sure that I never ran it into anything hard enough to cause that type of damage, but how hard a crash would have done that? Just a bump, or a "fly over the handlebars" collision?
#8
my 11.8, not a kink or chrome crack to be found?,,,,BD
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So many bikes, so little dime.
So many bikes, so little dime.
#9
juneeaa memba!


Joined: Oct 2003
Posts: 5,631
Likes: 5
From: boogled up in...Idaho!
Bikes: Crap. The box is not big enough...
Pictures and story are here: https://www.geocities.com/fritz125541/Jaubert I had quite a time getting the original picture shown above below 100 meg so that I could post it. It doesn't show the frame kink all that well, but that may be the best I can do. There are no cracks or other indications of damage - all you're seeing is dirt and light reflections. What I am mostly trying to find out is whether this damage is from a crash probably before I owned the bike, or whether it could be from careless handling by movers. I am pretty sure that I never ran it into anything hard enough to cause that type of damage, but how hard a crash would have done that? Just a bump, or a "fly over the handlebars" collision?







