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  1. #1
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    Dent on downtube!!

    Hi everyone- I have a small dime sized dent on the side of the downtube of my Enduro SL. Its very shallow and smooth- no signs of stress on the aluminum or paint. Should I be concerned or is it just cosmetic?? Thanks in advance.
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  2. #2
    Forging Elite Awesomeness
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    From the looks of your pics, I'd say cosmetic.

  3. #3
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    Don`t worry about that nick!
    But Alu bikes should be check while cleaning, for cracks near the weld zone (once in a month or so!)

    Imagine if it was a carbon frame - then there would be some problems. CFRP don`t deform, but shocks that made that dent can brake internal layers (carbon filaments on the CFRP).
    With use, this fragility could lead to rupture.

    Planes fly with bigger dents!

  4. #4
    Wil109
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    I concur with Tkul,

    I was a military flight servicing mechanic on fast fighter jets a few years back and they do fly with bigger dents, in certain areas. I'm surprised thats the only dent you have, my SL has dents from the rubber stoppers on the fork that are bigger than the one you have posted here. Like Tkul says cracks and guages near the welds are a big cause for concern.

    Wil
    [SIZE=1]I love my bike and my bike loves me[/SIZE]

  5. #5
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    Hi Wil!

    Could you tell what fighters did you work?

    This is all about tube thickness. At the moment, using the technology available (hidrforming, butted tubes and various aluminum alloys) it`s impossible to make a very light / rigid / strong enough on impacts -> IMO.

    Spec. Enduros come close to the 13 kg, and has 150 mm travel (f%r) with double crown forks.

    Thats fantastic, I think and to achieve this kind of goals you have to go the "less is better" meaning less material/less thickness.
    In doing this, any major fall/hit may result in a dent. Is it worrying? It will depend. imagine that is rips the tube. This will introduce a very stressful point in both ends of the rip. Imagine a tissue with a sharp knife sticked in middle. Uppon movement it may move the knife increasing the rip in the tissue (it`s a simple way of seeing thins )

    With the carbon fiber (CFRP - carbon fiber reinforced pre-preg) the dent will not be shown.
    All the stress is there in the impact zone, and if your lucky you can the the lacquer crack... or some scratches on the surface.
    Problem is not near the surface, is beneath it and can result in major failure.
    I remember a problem that occur in a a bike (one major bike manufactures) - the cable boss is to salient and in a crash, he snapped! Being carbon... it ripped a bit of the down tube! MAJOR PROBLEM! Warranty wasn`t valid -> accident!

    IMO, dents are part of a MTB frame life! Don`t worry... check once in a while for cracks, only for your safety

  6. #6
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    Did these over one year ago I think. Bike has done tons since and no problems at all so I would not worry.




  7. #7
    I'm "bad" different
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    Quote Originally Posted by Wil109
    I concur with Tkul,

    I'm surprised thats the only dent you have, my SL has dents from the rubber stoppers on the fork that are bigger than the one you have posted here.
    Wil
    +1 on the stopper dents.

    the downtube will be fine. i would warn though about dents in smaller tubes such as the chainstays. I had a dent from a crash in the left chainstay that lasted about 6 months until I did a drop onto rock and the tube buckled. It wasn't a catastrophic failure, in fact I didn't even notice it had buckled until after the ride, but the chainstay was done!

  8. #8
    Now with More Wood
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    +2 on downtube/fork rubber stopper dent. Got those. Nothing to worry about much, apparently.

    I also have a nick in the left chainstay....been hitting big stuff with it and it has not budged, but now I'm worried...WeezPuff, was it easy to get a replacement? Do they charge much for it (assuming its not covered by warranty)?

  9. #9
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    Your all good its what happens when people ride their bikes like there ment to be ridden!!!

  10. #10
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    This is what it looked like after it buckled. As you can see it didn't completely give in but it wasn't safe anymore. The replacement was easy enough - Spec just sent another chainstay and the LBS bolted it on. The part was $160 and labor $30 - frankly I thought it was going to be more since this is an intricate little piece.
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  11. #11
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    did it bulked on a turn or a jump/hit lateral on the ground?
    Of course the bend can be dangerous... but the one shown originally theres no problem.

    Dents on upper tubes (on the upper section) can be dangerous, because of bulk after a jump.
    This wouldn`t have happen if thickness was higher-->bigger weight.

    WeezPuff:
    Can you show more pics & spec of your bike?
    It looks really great the ones you posted

  12. #12
    I'm "bad" different
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    The final buckle probably occurred when I landed a little crooked off a drop onto sandstone which has really high traction. The pre-existing dent just acted as a stress riser.

    Unfortunately I don't have any recent pics of the bike, but really it's bone stock except for the wheels - the front is a Mavic EX823 laced to the spec stout hub with a 2.5 Maxxis highroller and the back is a Mavic DeeTrax with a 2.35 highroller both running tubeless. It has added a few pounds to the bike but it was worth it to me. I've put EnduroMax bearings in all the pivots and the headset, and slick-honeyed the snot out of the fork and shock and man is the bike ever smooth!!

  13. #13
    Now with More Wood
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    Damn its grey like mine....I hope its not an omen....

  14. #14
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    i just dented my frame again yesterday right above the bottom bracket on the lower frame tube .
    its just the price of admission .

    like was said,-- its all good ----it just means that we really riding the things and are having fun !

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