Stripped Four Bolt Mounts

Discussion in 'Observed Trials Discussion' started by BenR, Jul 30, 2004.

  1. BenR

    BenR Active Member

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    I stripped one of my magura mounts.:wtc: :rolleyes: :slap: :eek: :dunno: What should i do? It still works with only one bolt but, it's lost alot of power. The bikeshop mechanic told me to get a helicoil, but he also said there would still be braking power lost. Is there any place I could send my frame to take off the old mounts and get new mounts welded on? Or would it probably be better to have trialsin order me a cheap x-alp of x-hydra frame?
     
  2. Elan

    Elan steve french

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    if your frame is aluminum, scrap you cannot get new ones welded on. helicoil might work. they arent too expensive. worth a try id say.
     

  3. AndyT

    AndyT New Member

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    You can tap them to 5mm...like my old monty.
     
  4. Shipley

    Shipley ..........

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    Definitely give tapping it out to a larger bolt a shot... should work fine.

    Stole my post Mikey..
     
  5. thetart20

    thetart20 TartyBikes

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    Tap out to M6x1.0... or M5 helicoil kit.

    Job's a good un :)
     
  6. BenR

    BenR Active Member

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    Does anyone know where i can get a helicoil? Why can't I have new ones welded on? Has anyone tried this before?
     
  7. AndyT

    AndyT New Member

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    Can you read? Tap them out. Go to a machine shop with your frame, they will do it for cheap. Don't bother with that helitrash, I've seen them fail in the same application...
     
  8. BenR

    BenR Active Member

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  9. Tanner

    Tanner New Member

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    Because you'll lose a LOAD of strength plasma cutting the old mounts off, and the HAZ (Heat Affected Zone) will be huge, and when they're rewelded on, the TIG welding will have a HAZ as well. In short, you'll lose more strength in the frame. Not worth it. Unless you have it re-heattreated. Just drill em out, and tap to a larger size. Like the TEX mod I have.
     
  10. aka Mr Floyd

    aka Mr Floyd New Member

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    Just a note on helicoils... If they are done correctly, they are better than the original threads into aluminum. They are used in many aircraft applications where a steel bolt is threaded into aluminum. The helicoil insert is steel like the bolt, so you don't constantly wear out the aluminum threads every time you loosen the bolts to adjust your brakes.

    When the threads on my old monty started to go I got a helicoil kit and helicoiled all 8 brake mount holes and they worked great for 5 years and as far as I know are still working for the guy I sold the bike to.

    Todd
     
    2 people like this.
  11. thetart20

    thetart20 TartyBikes

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    This man is in the know. Plus, it avoids all the faff of making all the slots in your mounts larger etc... to fit the M6 bolt in!
     
  12. BenR

    BenR Active Member

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    I guess a helicoil is the way to go. Does anyone know where i can buy them? Thanks.
     
  13. DanBowhers

    DanBowhers I farted.

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    Just for your reference there was a huge IF modifier in the pro helicoil side of this debate. Seeing as you dont know where to get one are you sure you know how to do it right? I would tap it if i was you. But then again if I was you you would be me and you would probably have killed yourself by now...LOL
     
  14. trialspads

    trialspads TrialsPads.com

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    They sell them everywhere like SEARS and any hardware stores like Home Depot. It's about $30~$40 for a good set.
     
  15. BenR

    BenR Active Member

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    Thank you Neko
     
  16. average mike

    average mike Guest

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    Ben did you ride the whole 7 springs comp with only 3 brake bolts?
     
  17. BenR

    BenR Active Member

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    Not exactly, I just stuck the bolt into the stripped mount.:joshers: Its holding up fine I guess. Some rear brake power was lost. Howd you do in the comp?
     
  18. average mike

    average mike Guest

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    I got fourth. Not exactly what i wanted to get, but i wasnt really riding well near the end of the comp.
     
  19. Hey, The same thing happened to me, I stripped one of the four bolt mounts. If you are going to get it tapped then get it done by a proffesional, tapping aluminum is very hard because it is so soft. Also the blocks of aluminum that the mounts are made from aren't that big so if you tap it larger and mess up, you can't really do anything about it besides buy a new frame. I ended up being able to just use a longer screw, but everyone I talked to suggested using a heli-coil. They are used in car engines also, so they are probably pretty strong. Does anyone know why they don't make steel magura mounts? It can't be that much more weight on a bike. Is it really hard to weld steel to aluminum?
     
  20. tomacropod

    tomacropod Rum Pig

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    sometimes the 4-bolt mounts are installed such that you can put a (longer) bolt all the way through and just put a nut on the other side. Might be worth looking at if a helicoil doesn't work.

    - Joel