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Front brake calliper bracket threads gone! Help!

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Took off my calliper the other day to rebuild it, upon putting it back on torquing it to 25NM the threads just completely went, looks like the previous owner has helicoiled it before! 

Any advice on what to do as I'm struggling to find a replacement bracket for a 1999 KTM exc 200 as they are slightly different to the other models upon looking! 

Would a helicoil work again or does it need an insert putting in from a proper shop!

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You could try to redo the heilcoil, but I would not expect great chances of success.

You probably need to look hard for a replacement bracket. You wrote that they are expensive, but so is the professional machining that you are going to need. To fix it properly, you are going to need to have new, strong, fresh metal closing the bolt holes, then drilled out and tapped for the proper size. This takes a professional machinist.  

There is a guy, Bruce Whitham, with a YouTube channel who does amazing stuff in this space. https://www.youtube.com/channel/UC6HG4kXPSgb1Bhx6CY9e6iw

Might give you some ideas on how to approach it.

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You may be able to drill and tap a slightly bigger size

Edited by bnr
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11 minutes ago, bnr said:

You make be able to drill and tap a slightly bigger size

Good idea, but make sure it is bigger, not slightly bigger. You need to completely clean out the old threads, with a root diameter of the new bolts (inner thread diameter) larger than the outer diameter of the old bolts. Go up by 2mm not a half-mm

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Thanks for all the help and feedback, After looking hard for a replacement bracket and not finding one that can guarantee good threads, I'm going to take it to my local shop, I have used them before and they are good, I'm hoping they will drill it out bigger then insert a new sleeve in to the same thread size as before! 

The old bolts that have been used are still fine and the threads don't looked damaged in any way, would you recommend new bolts? 

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