Singlespeed & Fixed Gear - Gnarly FGG Action

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View Full Version : Gnarly FGG Action


Chazzmeister
04-01-05, 12:10 PM
did anyone else see this jacked-up frame?

http://www.fixedgeargallery.com/2005/mar/Cb.htm


Steel is Real!


flythebike
04-01-05, 12:36 PM
Aluminum breaks. It has a finite fatigue life. It gets weaker and weaker throughout its life the more fatigue cycles it goes through and then it breaks. So you have to overbuild it to begin with to compensate for it getting weaker later on. That is the tradeoff for its light weight and reatively affordable nature.

If you want a frame that won't fail catastrophically, you'd better go with steel, titanium, or carbon.

BostonFixed
04-01-05, 12:43 PM
I think the problem was beacuse, as the owner wrote, that it broke in the exact spot where a bolt was. The frame material being aluminum probably didn't help either....


baxtefer
04-01-05, 12:44 PM
yeah holes through your downtube can't help with stuctural integrity....

BostonFixed
04-01-05, 12:47 PM
yeah holes through your aluminum downtube can't help with stuctural integrity....
I edited it so its better now...

Miracle Whip
04-01-05, 01:13 PM
If you want a frame that won't fail catastrophically, you'd better go with ............ carbon.

You're an idiot. More to the point, you're an idiot whose knowledge about frame materials would fit in a thimble.

But you're probably super cool on your fixie.

flythebike
04-01-05, 01:21 PM
Yes, a hole in your ALUMINUM frame would definitely reduce the fatigue stregth of the frame and increase the likelyhood of such a catastrophic failure. He is lucky he wasn't injured or killed.

stevo
04-01-05, 01:41 PM
i agree al. has a finite fatigue life, and in theory in can break catastophically. Empriically, my al. frame has been ridden daily for over 16 years. On road and off. Gathousands of miles annually. No failures and I have full confidence in the frame. Likewise, must of us dont sweat the 'finite fatigue life' of our handlebars, which take a beating.

now, if i had throughbolted the downtube and the seattube, I may not have such confidence.

flythebike
04-01-05, 01:44 PM
Certainly a well constructed aluminum frame could last a lifetime. Or longer.

d_D
04-01-05, 03:15 PM
i agree al. has a finite fatigue life, and in theory in can break catastophically. Empriically, my al. frame has been ridden daily for over 16 years. On road and off. Gathousands of miles annually. No failures and I have full confidence in the frame. Likewise, must of us dont sweat the 'finite fatigue life' of our handlebars, which take a beating.

That is a problem with pretty much all frames not just alu.
Steel frames can fatigue and break suddenly. Build a steel frame so it won't and it will be too heavy.

Chazzmeister
04-01-05, 03:41 PM
but I think the point is that aluminum's progressive metal fatigure malleability is a lot less than steel. Steel (And other metals) can be bent back and forth a lot before they progressively get weak enough to snap. Aluminum has a lot less elasticity before breakage. Thats the point.