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  1. #1
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    Snapping bolts - Shock mount

    Hi

    Just for curiosity has anyone else broken the shock mount pivot bolt on their Knollys. I broke on on my old Chilli and Now on the Carbon Warden. (where the top of the shock mounts to the linkage) The problem seems to stem with the bolt loosening itself a bit and then cracking snapping off at the thread.

    The first time with the Chilli was with the old style linkage and spacers, when the bolt snapped it bent the linkages as well.

    The second time with the Carbon Warden (New M8 size pivot bolt, which is hard to come across....) it luckily kept enough of the bolt captive to not bend the linkages. Admittedly this one was probably my fault for not checking the bolt after 300odd km of hard riding but I thought this problem had been fixed. I managed to find a replacement bolt from a distributor who said he had to replace someone else for the same problem previously.

    Is this something that other people have encountered? Ill grease this new one up heaps and maybe but a bit of thread locker on it. Would a solid shaft with retainer bolts / nuts on the end be a better solution from the factory as the pivot would have a bit of rotational force on it?

    I have correct sag on the bike with a Push 11/6 shock.


    Thanks

  2. #2
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    I rode my chilcotin in the PNW (Shore etc) for almost 2,000 miles over a bit more than 4 years. Broke one bolt on a drop with hard landing (Corkscrew) on year 3, and after that I would occasionally check for bolt wear, and replaced annually after that. Looking at the old bolt, there was obvious wear.

    I also have a carbon Warden with 11-6 and have never heard of anyone snapping that bolt. I find it very unlikely. I beat up my Gen 1 Delirium and Gen 2 Podium at Whistler and CAT 1 DH racing for about 5 years each and never touched that bolt.

    Since the Warden has the mk2 linkage, it may have more rotation on that bolt than the Podium. However. I think that 8mm bolt should last 4-5 years minimum, and would be fine for replacement at 2 years, assuming equal stress to the Chilcotin's 6mm bolt and the non 3D rockers it had.

    I think something rare happened with your install of the 11-6. I agree with using a good waterproof great on the bearing surface and locktight. Check during the first ride and every ride for a month afterwards to make sure it doesn't back out.

    I weight 210+ RTR atm so its not like I am easy on bolts.
    Regional Race Manager, Knolly Bikes
    Washington, Oregon, Montana, Idaho, Wyoming

  3. #3
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    I snapped one Saturday on a carbon warden. I am guessing it had worked its way a little loose, Im about 215 RTR so I'm not too easy on components either, Either way it broke, Im going to keep an eye on it to make sure its not backing out, snapping a 12.9 grade bolt shouldn't be a common trend lol

    Snapping bolts - Shock mount-51164583215__d4441f7b-522a-4a84-8402-cef3d8789532.jpg.jpg

  4. #4
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    Quote Originally Posted by nzerk View Post
    I snapped one Saturday on a carbon warden. I am guessing it had worked its way a little loose, Im about 215 RTR so I'm not too easy on components either, Either way it broke, Im going to keep an eye on it to make sure its not backing out, snapping a 12.9 grade bolt shouldn't be a common trend lol

    Click image for larger version. 

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    Any nice clear closeup pics of the actual fracture surfaces?

  5. #5
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    Ill have to try and find mine, I think I lost it on the way back from NZ but it failed in exactly the same spot

  6. #6
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    Hopefully these are close enough

    Snapping bolts - Shock mount-1.jpgSnapping bolts - Shock mount-2.jpgSnapping bolts - Shock mount-3.jpgSnapping bolts - Shock mount-4.jpg

  7. #7
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    Quote Originally Posted by nzerk View Post
    Hopefully these are close enough

    Click image for larger version. 

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    Those are super pictures.

    For sure that is multi-cycle fatigue - was not caused by one big hit. By the looks of it it migrated at least 2/3 of the way through before it had the final catastrophic failure.

    I would suggest periodic removal of these / clean and inspect real close. Re-tighten everything with a torque wrench. Too much torque can do a lot more damage then an under-torqued bolt.

  8. #8
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    What size bolt is it?

  9. #9
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    I've had issues with this bolt on multiple frames. I've kind of chalked it up as the weak point/design flaw of Knolly frames. I have had the bolt snap/bend multiple times each on the Gen 1 and Gen 2 Endorphin. I now own the Warden C with no issues so far but only been riding it a couple months. My wife has had a Gen 1 Endo, Delirium-T and now Gen 3 Endo with no bolt issues but she's a lot smaller and doesn't ride as aggressively.

    I only weigh about 150lbs but ride pretty aggressively.

  10. #10
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    Thanks for the head's up I bought a couple spares. Nice to have for peace of mind when you are on a long road trip.
    Safe riding,

    Vik
    www.vikapproved.com

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