Exhaust Exhaust stud hole is stripped.

Discussion in '2-Stroke Engines' started by Waxxumus, Oct 24, 2015.

  1. Waxxumus

    Waxxumus Member

    Well, I pulled a noob and overtightened my exhaust stud, now the hole is stripped and will not hold a screw or stud otherwise. What would be my options here to reintroduce threading to the exhaust mount?

  2. butre

    butre Well-Known Member

    threaded inserts or simply thread it for something like 3/8
  3. dougsr.874

    dougsr.874 Active Member

    Buy yourself a set of taps....not very expensive at your local hardware....chances are you can retap the hole for a 6mm...which is the size of the original...if not use the next largest size and buy a bolt that size...
  4. crassius

    crassius Well-Known Member

    oversize or heli-coil goes well - for clutch side hole, one can break a bit of fin off behind the stud hole to let the threading tool go deep into the hole, for drive side hole, removing the cylinder & drilling right thru to the head stud channel inside gives good depth for your tool
  5. BWB

    BWB New Member

    heli coil makes it stronger than original too.
  6. HeadSmess

    HeadSmess Well-Known Member

    one of the few times i would smack you if i could...


    use an M8...the next size up is actually M7, but that is such a rare size to find...its not worth it.

    neither is a helicoil, unless you do constant tear downs, in which case, the kit can be worth it. you do every bolt, and never fear stripping em out again.

    a mechanic "may" helicoil it for you, but the price can be highly variable...from a beer or two, to almost the cost of the helicoil kit itself.

    and, while they are really easy, i have seen so many people stuff up helicoils simply because they have never done one before...

    get a new cylinder as last option..actually, thats cheaper than the helicoil option!

    oh, yeah... hack into the cylinder behind the stripped hole, with some luck you can squeeze a nut in behind... you can get lil skinny "locknuts" that are only half thickness...
  7. butre

    butre Well-Known Member

    Chevy and Ford mix imperial and metric all the time, works for them.

    you want to hear something really naughty? I've retapped metric nuts to fit over imperial bolts and vice versa when in a pinch on numerous occasions, and some of those kludges are still rolling around
  8. HeadSmess

    HeadSmess Well-Known Member

    as do polaris, certain BMW bikes, toro, etc... its still a nasty habit to get into! i seriously hate working on anything that needs two different measurement spanner sets. metric all the way. long live japan, they at least found a good standard and stick to it.

    but, could be worse...try working on old british machinery where they seemed to design a new thread for each and every application :eek:
  9. butre

    butre Well-Known Member

    at least bsw has some kind of rhyme or reason to it. try using a 10mm wrench on a stud with quarter inch thread, that really trips people up
  10. mrbg

    mrbg Member

    New cylinder 25 bucks