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Old 06-15-08, 11:30 PM   #1
zambaccian
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How safe is it to ride this crashed steel frame?

I have a frame that was in a front-end crash. Both the top tube and the downtube have a slight bulge/bend. About an inch from the head tube lug, they have a sort of bulging ring all the way around.

I'm wondering if it'd be a bad idea to rebuild it as a cheap bike for a friend. Would only be ridden on the street, nothing too hard, but of course there's always the possibility of a pothole.

So I'm wondering:
- how likely it is to break / crack if it's treated somewhat gently.
- if it does break, how likely is it to be catastrophic?

I'm thinking of going for it, just because both tubes would need to break at once to have a serious crash, right? Is this a stupid idea? Do you need pictures?
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Old 06-16-08, 05:39 AM   #2
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How good a friend are they?
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Old 06-16-08, 07:07 AM   #3
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How good a friend are they?
Would they let you buy them some life insurance, with you as the beneficiary?
Don't know what the chances are that the frame would break, but the odds would be much much higher compared to an undamaged frame.
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Old 06-16-08, 10:57 AM   #4
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Yeah, I'd be reluctant to do it. If you can see the distortion, and it's all the way around both tubes, that sounds bad to me. Mind you, I have no expertise in tubing strength / resiliency. It still sounds scary.
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Old 06-16-08, 11:08 AM   #5
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Don't do it.

Gentle use, hard use... it's impossible to tell how close to failure that frame is right now.
And yes, a tube failure means that the bike will fold up... unless your friend isn't moving at the time, he's
going to get hurt.

I had a steel Fuji that was damaged like that... Rather than repair it at all, I used it indoors, chucked into a mag resistance trainer. One day, I decided to see why the headset was so loose. When I went to adjust it, I found that the head tube had cracked up the back... I hadn't noticed that after the crash, so I think that maybe the stress of being attached to the bent top & down tubes, and having to support my weight, caused it
to fail.

In short, you don't know what other damage there is to that frame.

Better suggestion: If the components are any good, buy a secondhand frame & fork, and transfer the good bits.
Check w/LBS to see if there's one hanging up in the back.
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Old 06-16-08, 12:29 PM   #6
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Is this a stupid idea? Do you need pictures?
Yes.
No.
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Old 06-16-08, 01:21 PM   #7
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Stupid idea. Pick up a clean used frame, reuse the components.
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Old 06-16-08, 01:48 PM   #8
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Find a different frame.
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Old 06-16-08, 05:10 PM   #9
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The frame is finished - don't rebuild it or your friend will be finished too! It could/ is likely to - fail at any time.
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Old 06-16-08, 06:07 PM   #10
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The bike is toast. If the tubes are bulged, it probably handles differently because the head tube angle has changed.

I rode a bike that had similar damage for several months. Eventually, a crack develops at the bulge/wrinkle that will propagate all the way around the tube and cause a catastrophic failure. One day I was riding about 15 miles from home when I noticed the bike felt really loose. I looked down and the down tube had cracked and was held by less than 1/2 inch of metal. I'm convinced if I had ridden another 5 minutes, the frame would have completely broken and I would have done a face plant.

A friend came and picked me up.
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Old 06-16-08, 06:09 PM   #11
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What happened to the last guy who rode this bike? Ya know, I'm gonna go against the popular consensus here and recommend that you fix this bike up and give it to your friend. This can become a cursed bike that is passed around the community killing anyone who dare ride it.

This would make a badass movie.
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Old 06-16-08, 06:26 PM   #12
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Originally Posted by zambaccian View Post
I have a frame that was in a front-end crash. Both the top tube and the downtube have a slight bulge/bend. About an inch from the head tube lug, they have a sort of bulging ring all the way around.

I'm wondering if it'd be a bad idea to rebuild it as a cheap bike for a friend. Would only be ridden on the street, nothing too hard, but of course there's always the possibility of a pothole.

So I'm wondering:
- how likely it is to break / crack if it's treated somewhat gently.
- if it does break, how likely is it to be catastrophic?

I'm thinking of going for it, just because both tubes would need to break at once to have a serious crash, right? Is this a stupid idea? Do you need pictures?
You're a pretty ****ty friend if you build it for someone to tool around on. Even if it is low speed.
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Old 06-16-08, 07:03 PM   #13
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[QUOTE=
This would make a badass movie.[/QUOTE]

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Old 06-16-08, 07:16 PM   #14
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Even a slow rider hits potholes hard.

And if this is an aluminium frame then it's probably already got cracks in it if it's bulged that hard. Steel is more forgiving but even if you never get a full on crack then the steering geometry is messed.

Toss it and find another frame. And this is coming from someone that is reluctant to toss anything.

Either that or sell the movie rights quick like and set up a trust fund for your friend...
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