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  1. #1
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    Broken / cracked frames, anyone?

    Any of you 200+ pounders ever have something like a cracked or broken frame happen to you? Here's my first experience with it. I bought this bike last December.

    2005 Kikapu - cracked swingarm

    Tell us your stories and post some pics of the damage.

  2. #2
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    Quote Originally Posted by hallin222
    Any of you 200+ pounders ever have something like a cracked or broken frame happen to you?
    I've cracked three 2002-2004 Specialized Enduro Frames. The crack on the first frame was near the shock mount and was apparently not that uncommon for those 2002 frames. The other two frames cracked in roughly the same location, just above the weld on the seat tube. (Or what amounts to a seat tube on one of those older Enduros.)

    I've also cracked a 2004 Iron Horse Hollowpoint frame. The top tube developed a slight crack near the head tube. I only discovered it because the bike had developed a creak which I thought at first to be a headset creak. Here's a link to the story and picture: 2004 Hollowpoint - cracked frame

    In all cases, the cracked frames were replaced under warranty. The Specialized frames were replaced within one to two weeks with no out of pocket cost to myself. I am very, very pleased with the Specialized warranty. It took several months to get a replacement for the Iron Horse frame.

    I weigh between 210-215 with gear. Back in my road biking days, I weighed perhaps 170 and still managed to break the chainstay of my circa 1988 Trek 1200.

    What did all of these frames have in common? They're all made of aluminum. Someday, I'll try a steel frame to see if it holds up better...

  3. #3
    Your bike is incorrigible
    Reputation: Guyechka's Avatar
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    I've cracked one frame so far. '04 San Andreas frame cracked at the seat/shock mount. It was replaced under warranty, and the new mount area looks a lot beefier.

    I would agree somewhat with the aluminum issue. I have ridden for quite some time, and never has a steel frame broken. Alas, it is becoming more and more difficult to come by steel--unless you go custom.
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  4. #4
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    One thing that is certain is that guys and gals like us that weigh over 200 lbs will eventually have frame fatigue or failure if the bike is riden long enough and or hard enough. Aluminum fails eventually, always does, so does steel, just not as frequently. Even if the tubing survives usually a frame will fatigue around the welds. I have only cracked one mtb frame that was aluminum, and that was when I was alot younger and only weighed about 170 pounds. When I was a kid I broke three BMX frames which were all 4130 chromo.
    [SIZE=5][/SIZE]

  5. #5
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    Former Clydesdale Breaks Surly KM!!

    About an hour ago my Karate Monkey bent and cracked on a small jump! I am still in shock. For some reason I can get the pics to load.

  6. #6
    bi-winning
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    Obviously you don't need to be a clyde to crack an aluminum frame. I cracked a 2002 Giant Rainier @150lbs. Being 200+ definitely is harder on equipment, and therefore makes it more likely to fail.
    When under pressure, your level of performance will sink to your level of preparation.


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  7. #7
    Former Bike Wrench
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    2002 Iron Horse Hollowpoint

    I cracked a 2002.5 Iron Horse Hollowpoint, but I think a lot of them broke in the same place (on the toptube about 1.5 inches back from the headtube). It looks like IH ran a weld from the downtube/toptube interface right at the butt of the toptube, causing a stress point. I got a 2003 Hollowpoint Team as a replacement, but it took 4 months!!! When I purchased a new full suspension this fall (I sold the Hollowpoint in 2004), I considered the IH MK III, but the lousy warranty service was the biggest factor in not buying one. Too bad, I like the way the DW link rides, but service sells and Iron Horse lacked it when I needed it.

  8. #8
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    2002 Trek 8000

    I cracked a 2002 Trek 8000 frame (ZR 9000) last summer - 6-2006.

    Cracked it just above the bottom bracket - roughly 300 of 360 degrees. Trek sent me a new 8900 frame within two weeks. Good stuff.

    I am 6-4 and 208...

  9. #9
    Slow climbin' clyde
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    Here's what Rocky Ridge did to my Fuel 98. Trek replaced the front triangle with no questions asked.
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  10. #10
    Double-metric mtb man
    Reputation: Psycho Mike's Avatar
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    I've been fairly lucky to date (knock on wood) and haven't bent or broken a frame.

    Wheels and tires on the other hand.... I should just carry taco sauce and an anti-venom kit with me all the time.
    As if four times wasn't enough-> Psycho Mike's 2013 Ride to Conquer Cancer Page

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  11. #11
    Spring! Spring! Spring!
    Reputation: bear's Avatar
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    Blarg, don't know if I still have pics handy.

    4 Cannondale HT frames from '92 through '02, they had LOTS of well earned milesage each though, never on a weld, always just somewhere on a fatigued tube. Pretty expected. The big 'dale always took care of me though and supported their warranty "to the nines."

    In '01 I switched from XT hubs to Chris King, I managed to shatter four freehub bodies doing steep granny-gear climbing in Cameron Park in Waco, TX. I got it with the heavy-duty stainless-steel driveshell. I have over 10k miles on these hubs now and they're still going strong. I would never go back. I'll pay for another set when I have to, if I have to sell my car.

    '02/'03 model year Spec Enduro - broke it five times; main triangle forward-shock mount, chainstay twice, swing-link twice. All were weld failures. Specialized always stood behind their warranty and my LBS was fabulous beyond description in supporting it. The other failure I had on that bike was the fork dropouts, on an '03 Zoke MX Comp. I got back from a trip to Moab and both dropouts rear sides had cracked from the dropout inside straight back, almost to the back (had like 2mm of metal left).

    I put in between 2k and 3k miles on my mtb annually. I'm getting lighter-riding but I'm not there yet.

    My current bike I've had since '03 (after the 5th failure we sold the freshly rebuilt with new frame Enduro) and I moved to an '03 Titus Quasi-Moto with a Fox Vanilla 125 fork.

    The titus has over 7k miles on it, the fork has been rebuilt once by PUSH Industries.

    I've broken a couple pedal springs (Egg Beaters) over the last couple years.

    I'm not saying we need to spend $5k on a bike, I'm just saying that I in no way doubt (nor does my wife) that it was the right solution for me at the time.

  12. #12
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    Aluminum vs Steel Frames

    Interesting discussion here..... BTW I'm an elderly huge-clyde noobie almost ready to retire from engineering............ I'd to briefly chat about the metallurgical differences between steels and aluminums and why they crack differently.

    Steel materials (ferrous) have an "endurance limit".... which means if they are stressed to approximately 1/2 or less of their tensile strength, they'll last forever and never, ever break due to fatigue..... exclusive of manufacturing defects.

    Think of an automotive drive axle..... as the wheel turns, the shaft rotates between compression and tension. If the vehicle is properly loaded within its design constraints, the drive axle will never, ever break because its stressed well below the "endurance limit" of that particular steel.

    Non-ferrous materials such as aluminum and copper do not have an "endurance limit". Copper and aluminum sheets, for example, when flexed (alternating tension & compression) will eventually develop a fatigue crack and finally break completely in two. (A properly flexed steel spring, however, will never break unless its twisted or extended too far and goes beyond the endurance limit or into plastic deformation)

    So it is with non-ferrous bike components..... eventually they will break. So what's an engineer to do??? The answer is limited-life components. Aluminum components are designed with a given number of jumps or cycles or miles or hours of service in mind. That is to say, lightly stressed ("heavy duty") parts last longer than heavily stressed (lite duty) parts.

    So you calculate the anticipated stresses, throw in a real-world safety factor and bam.... you can predict the life of the part under the anticipated stress conditions. Aircraft have some life-limited aluminum parts which are replaced when their service limit has been reached.

    The anticipated stresses of road bikes are relatively easy to predict. The big problem, from my limited vista, is predicting the stresses of mountain bikes..... talk about an interesting guess!! I'm sure the MTB design pro's have this down to a reasonable science by now.

    Well that my $.02 worth..... the punch line of this rhetoric??? Aluminum is cool, but we need to keep the loads & stresses down or cracked frames will be the price of admission for having super-fun times.

    BTW, I carefully (boringly) ride an aluminum Rockhopper desperately trying not to bust up the frame 'cause of my significant girth..... no jumps for this old guy!!

  13. #13
    bi-winning
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    Quote Originally Posted by roller-blob
    Interesting discussion here..... BTW I'm an elderly huge-clyde noobie almost ready to retire from engineering............ I'd to briefly chat about the metallurgical differences between steels and aluminums and why they crack differently.

    Steel materials (ferrous) have an "endurance limit".... which means if they are stressed to approximately 1/2 or less of their tensile strength, they'll last forever and never, ever break due to fatigue..... exclusive of manufacturing defects.

    Think of an automotive drive axle..... as the wheel turns, the shaft rotates between compression and tension. If the vehicle is properly loaded within its design constraints, the drive axle will never, ever break because its stressed well below the "endurance limit" of that particular steel.

    Non-ferrous materials such as aluminum and copper do not have an "endurance limit". Copper and aluminum sheets, for example, when flexed (alternating tension & compression) will eventually develop a fatigue crack and finally break completely in two. (A properly flexed steel spring, however, will never break unless its twisted or extended too far and goes beyond the endurance limit or into plastic deformation)

    So it is with non-ferrous bike components..... eventually they will break. So what's an engineer to do??? The answer is limited-life components. Aluminum components are designed with a given number of jumps or cycles or miles or hours of service in mind. That is to say, lightly stressed ("heavy duty") parts last longer than heavily stressed (lite duty) parts.

    So you calculate the anticipated stresses, throw in a real-world safety factor and bam.... you can predict the life of the part under the anticipated stress conditions. Aircraft have some life-limited aluminum parts which are replaced when their service limit has been reached.

    The anticipated stresses of road bikes are relatively easy to predict. The big problem, from my limited vista, is predicting the stresses of mountain bikes..... talk about an interesting guess!! I'm sure the MTB design pro's have this down to a reasonable science by now.

    Well that my $.02 worth..... the punch line of this rhetoric??? Aluminum is cool, but we need to keep the loads & stresses down or cracked frames will be the price of admission for having super-fun times.

    BTW, I carefully (boringly) ride an aluminum Rockhopper desperately trying not to bust up the frame 'cause of my significant girth..... no jumps for this old guy!!
    Thanks for chiming in. Myself, being a first year engineering student, am interested in the metallurgical properties. This is actually right along the lines of the stuff I am currently studying myself. Stress/strain/plastic deformation/strain hardening/fatigue... Oh I've got so much to learn
    When under pressure, your level of performance will sink to your level of preparation.


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