Dec 16, 2001 4:15 PM
|With all of the frame tube materials, tube sizes, etc. is there any kind of a rule of thumb for how long a given frame SHOULD last (in terms of miles) be it a svelte Italian or something that could double as a boat anchor ?|
Dec 16, 2001 5:14 PM
|There way too many variables to predict frame life. Rider weight and riding style, combined with the kind of use and road conditions are one set of unknowns. Then you have the details of how any given brand/model of tubing was assembled, plus the tubing itself. Since no manufacturer EVER shares information on their customer's experiences with frame life, and independent tests have lacked any statistical validity or a defined correlation with actual use, you're left with NOTHING.
The only rule of thumb you could propose is that in general, lighter frames are more likely to fail in a crash or under heavy use, but that doesn't provide any useful data. Early OCLVs had a reputation for cracking, but even that might have only been in proportion to the very high sales and the likelihood that they were used more for racing. Composite frames can be subject to fiber failure, fiber pullout, or epoxy matrix failure, so they need to be designed to compensate for that. While Al has a finite fatigue life (weakens with every flex), steel and Ti will last forever if they don't exceed their fatigue limit in flexing. So an Al frame has to be over designed to prevent failure, and that is routinely done. Still, there are certainly steel and Ti frames that fail, so there is much more at work than the simple properties of the metal or any given alloy.
|Agreed, that's why...||John-d|
Dec 17, 2001 2:24 AM
|sites like this actually have some use.
Any frame that suffers will very quickly be exposed here.
It should not matter too much providing the use is within the confines of the purpose stated in the sales literature. The frame should not crack, if properly designed, otherwise all bikes would suffer the same, which they don't.
So check through here and discard any where repeats of cracking are complained about. If a few people think that such and such a frame cracks, then it probably does.
That's what I did anyway.
|re: Frame Lifespan||Indiana Rider|
Dec 17, 2001 9:18 AM
|I had a TREK aluminum frame that was 10 years old and had approximately 30,000 miles on until I ran over it with my truck this summer...darn thing broke.|
|So there's your answer...||mr_spin|
Dec 18, 2001 10:10 AM
|Incontrovertible evidence shows that a Trek aliminum frame will last 10 years and 30,000 miles, after which you should drive your truck over it to prevent its reuse.