Why are aluminum GT frames so weak?
07-24-20, 09:06 PM
#1
Uruguay
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Why are aluminum GT frames so weak?
Why alluminum GT frames are so weak? I'm leaving some pics here of a GT i bought today in really bad conditions. It's not the first one but as i like parting out bikes so much, i "wrenched" it with my bike and took it home.
07-24-20, 09:44 PM
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They're great trash material.
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07-24-20, 09:45 PM
#3
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It ain't the years, honey. It's the mileage.
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07-24-20, 11:51 PM
#4
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07-24-20, 11:58 PM
#5
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Its a 10-20 year old mountain bike that is wrecked. Hardly uncommon.
you could replace the brand and pics with any number of others.
you could replace the brand and pics with any number of others.
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07-25-20, 05:24 AM
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That bike looks abused, wearing a hole in I'm guessing a chain stay from rubbing on a pedal or tire is hardly the frame's fault. The rear drop outs being worn are not uncommon with aluminum frames.
Aluminum bikes can live a long life. I just converted a maybe 30 year old Cannondale aluminum frame MTB to an ebike. 10 years ago the frame was so worn at the drop out the rear wheel would pull forward with normal riding, I had to fabricate stainless steel plates for the sides of the drop out to get the wheel to stay put.
But other than that it has held up to a 240# rider all these decades. Hopefully it will hold up to the emotor for 20 more.
Aluminum bikes can live a long life. I just converted a maybe 30 year old Cannondale aluminum frame MTB to an ebike. 10 years ago the frame was so worn at the drop out the rear wheel would pull forward with normal riding, I had to fabricate stainless steel plates for the sides of the drop out to get the wheel to stay put.
But other than that it has held up to a 240# rider all these decades. Hopefully it will hold up to the emotor for 20 more.
07-25-20, 06:36 AM
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My 20 year old Zaskar (last year made in the US) would belie your statement. Other than scratches in the paint from continuous off road use (including a stretch with a mid-drive motor), it's pristine. Will post a photo in a day or so.
07-25-20, 10:01 AM
#8
Uruguay
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we want to see that Zaskar! Do you know the model and year of the bike i showed? I think it could be a 2008 model aprox so that would be something to think about for example, if GT's materials were better back in 1990s, although a friend of mine told me he repaired and saw a lot of 90's GT aluminum bikes being brand new and cracking some weeks after
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07-25-20, 10:10 AM
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On to the issue of the GT being a weak bike, nothing that you have shown on this bike is due to the bike being “weak”. Everything is due to user error...and very hamhanded error at that. A strong frame that has a hole that size burned into the chainstay would break. The dropouts look like someone took a grinding wheel to it in an effort to make the dropouts horizontal. Kind of sad really.
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07-25-20, 10:18 AM
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Treat any mountain bike like a BMX bike and you can break the frame easily. GT aluminum mountain bikes were the toughest bikes on the market in the 1990s, but even they would eventually fail after enough 20-foot drops.
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07-25-20, 11:27 AM
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I don't understand why someone would waste time thinking about that carcass much less taking pics of it.
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07-25-20, 11:27 AM
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07-25-20, 12:12 PM
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You did not just buy a New Bike, right?
Because you thrashed the bike, and they did not use steel , you wanted lighter did you not?
Off road riding is shortening its use life..
...
Off road riding is shortening its use life..
...
07-25-20, 12:22 PM
#14
Uruguay
Thread Starter
idk, for me it's interesting to see the damage some bikes have and then figuring out the motive. I think that dropouts were the first ones to fail and then as the wheel was twisted, it "burned" the aluminum. Apart from the frame the bike was one of the worst i have seen, previous owner must be Hulk 😝
07-25-20, 12:25 PM
#15
Uruguay
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i bought it just to part it out so my preferences did not apply when buying it. If u ask me, i would prefer a 98' Palomar made of chromoly
07-25-20, 01:25 PM
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Looks like it spent considerable time with a street person.
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07-25-20, 02:33 PM
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Bad picture. Just de-motorized (mid-drive BBS02) 2000 Zaskar, then needed to have the bottom bracket chased.
Don't know much about other GT model years, but the C&V guys are experts.
Don't know much about other GT model years, but the C&V guys are experts.
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07-25-20, 11:40 PM
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idk, for me it's interesting to see the damage some bikes have and then figuring out the motive. I think that dropouts were the first ones to fail and then as the wheel was twisted, it "burned" the aluminum. Apart from the frame the bike was one of the worst i have seen, previous owner must be Hulk 😝
Your theory as to how holes were created is absurd.
You mentioned you bought this bike to part out, yet you also posted that besides the frame(that is broken and you make fun of) the bike was one of the worst you've seen. Why would you buy a bike to part out that has a trashed frame and parts thst are even worse?
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07-26-20, 03:33 PM
#19
Uruguay
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You asked why all aluminum gt frames so weak. Its been stated by all others besides you that they arent and thst this example is due to misuse/abuse.
Your theory as to how holes were created is absurd.
You mentioned you bought this bike to part out, yet you also posted that besides the frame(that is broken and you make fun of) the bike was one of the worst you've seen. Why would you buy a bike to part out that has a trashed frame and parts thst are even worse?
Your theory as to how holes were created is absurd.
You mentioned you bought this bike to part out, yet you also posted that besides the frame(that is broken and you make fun of) the bike was one of the worst you've seen. Why would you buy a bike to part out that has a trashed frame and parts thst are even worse?
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07-27-20, 07:06 AM
#21
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Waste of digital film.
