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I'm in the market for a threading repair kit. I live in Australia so the closest options for me are to go to Supercheap Auto or Bunnings Warehouse (links to products from those stores). These repair kits have metric sizes e.g. m6, m8, m12, etc. What is the right sized repair kit for my crank arm to be re-threaded?

My crankset is Shimano Deore FC-T6010 170mm.

No idea which one will work. Thanks for any help.

  • Made to an answer. – mattnz Feb 26 '18 at 3:17
  • so what do i do then? Buy a new crankset i just got the bike today! – HashTables Feb 26 '18 at 3:20
  • You're assembling a new bike you just bought today and the pedal is stripped already? Is this a cheap entry level bike? Could be an indication this bike won't last very long if this is the quality of the parts. Consider returning it as a lemon under the consumer guarantee act (which only gives you a short time to do so.) – Criggie Feb 26 '18 at 7:00
  • @Criggie It cost me 850, i guess its entry level. I think it was my own fault though i don't recall screwing the pedals the wrong way though, maybe i did do that but immediately realised what i was doing and by then it was too late. Must be because the crankset is made up of weak metal and can easily strip?? – HashTables Feb 26 '18 at 7:29
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    Pedals should be screwed in by hand ONLY on the 2-3 first turns. If they don't go in easily there is a strong chance that they are on the wrong side. Left side left thread, right side right thread. – Carel Feb 26 '18 at 11:46
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Neither - If you use metric for the thread repair, where will you get metric threaded pedals from? Also be aware the left pedal is left hand thread.

Suggested reading How to fix a stripped pedal crank

Better than those would be the correct tools for the job - e.g. https://www.amazon.com/Unior-Pedal-Tap-Thread-Insert/dp/B001PTCKJO - Of visit the LBS and get them to do it for you (probably for less as they already own the taps, so you only pay for their time and the coils.)

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The vast, vast majority of pedal threads are 9/16" x 20 TPI. In nearly a decade in the bike industry I am aware of zero metric-threaded pedals (amazing, considering the lack of standardization in other parts!). The taps we use at the shop cost much more than the cost of a generic replacement crank (assuming it's the non-drive side, which it usually is).

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    Why is it "usually the non-drive side" ? Purely because that's the left hand thread and easier to crossthread ? – Criggie Feb 26 '18 at 7:01
  • Usually but not always -- the only knackered crank arm thread I've handled was on the right -- and steel. At some point the top couple of turns had been chewed up, and it was hanging on by the rest, until I stood on the pedals – Chris H Feb 26 '18 at 8:54
  • Yeah, I imagine the reverse threading just confuses folks, as we see it most often on new bikes that people try to assemble themselves. Weirdly, the NDS crank is the first to loosen off the spindle too, which almost never happens to the DS crank, but I lack the mechanical knowhow to explain why. I'm sure there's an obscure Jobst Brandt newsgroup post out there somewhere telling all about it. – Nathaniel Hoyt Feb 26 '18 at 15:22
  • Wild guess, the 'wrong direction' left thread is not tightened as much as the right - would be interesting to put a torque wrench on a bunch of bikes assembled by amateurs and see if there is a difference between the pedals. – mattnz Feb 26 '18 at 19:47

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