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?

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.

Is there a crack in the lower lug as well? Looks it.

Beats me why the tube doesn't have a matching stretch or bend on the top...

-Kurt

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.

My thoughts exactly.

East Hill

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.

Pictures and story are here: http://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?

I have a few bikes that had pretty severely bent forks with no apparent frame damage? The worst was
my 11.8, not a kink or chrome crack to be found?,,,,BD


http://i114.photobucket.com/albums/n...er/Veeger1.jpg

The impact damage depends on the weight of the ridden bicycle, the forward speed, and the quality of the materials involved in the impact. I don't think you could get a kink like this wheeling it into something, but you might if you dropped it headfirst off of a loading dock. My kink collision damage resulted from an impact with a car, like John. I've been in the middle of huge crashes in races, with my bicycle completely airborne, and the bicycle has escaped (generally) unscathed.