Pretty bruised and scraped after the sudden frame failure of my Jamis Nova Pro aluminum cross bike particularly since I'm a lighter rider (150lbs) and most of my riding would be described as heavy gravel/light trail). Any other experiences with aluminum frame failures with this or other brands other folks have had?
Where and how did it fail? Any material can catastrophically fail.
Occurred while standing to pedal on flat gravel surface. Pic attached. Have you observed similar failures on aluminum or other cyclocross bikes that were non-crash related?
Wow. That is frightening.
Had a friend with a ti frame do that. Can you see if the down tube crack is uniformly colored or is part of that break darker or "softer"? It would indicate that you likely had a small crack that started to develop there and then expand until the whole thing broke.
Also, that's a lot of steerer tube on there. That could be adding a significant additional stress load on the head tube area.
2 years old tops. Right now the bike is at the dealer going through the warranty process-- I'll look more closely when I get it returned. Helpful to hear that this may have happened to others.
Not sure about the steerer tube contribution-- they would be able to assess/test this at the factory level and I would hope not let buyers walk out with a compromised bike?
I can see Anne's point on the steerer tube. That is ALOT of spacers and kinda begs the question if the bike was the right size/fit. If you were doing alot of out of the saddle hammering, that could be more stress than it is designed to take given the extra leverage.
Hope you are able to get a good resolution from the warranty process.
I can get behind the physics of the additional spacers making the steerer into a longer lever & putting more stress on the down and top tubes at the area of the failure, but if the frame failed for that reason it's just a bad design. Especially considering the fork looks to be stock, so seemingly the manufacturer supplied it with enough steerer to be able to mount the stem at that height.
Out of curiousity, it is a normal aluminum frame or a scandium frame?
From Jamis 2012: "7005 double-butted aluminum, tapered head tube, top tube formed with portaging flat, carbon fiber monostay"
Appreciate the input-- very helpful in trying to sort out contributors from set-up vs. manufacture. I have heard of handling challenges with higher stem but not for frame loading challenges. (Also emailed Lennard Zinn to get his input). It would seem that manufacturers would flag that (sort of opposite of: "you can only go on this ride if you are 'this' tall.") for dealers/riders if stem height compromised the frame. The bike fit me really well around some physical issues and both sad to lose it --also moving forward need to know if I spend the $$ to get a custom frame or even a hardtail if this is just a limitation of frame building/design in general. (I'm not fast enough to warrant the $$ but avoiding x-rays and missed work may be)
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