Stripped studs in exhaust mounting help!

Discussion in 'Motorized Bicycle General Discussion' started by AaronF, Aug 26, 2009.

  1. AaronF

    AaronF New Member

    Joined:
    Aug 24, 2009
    Messages:
    389
    Likes Received:
    0
    It seems as i ran into another problem.At the exhaust mounting,the inside of the cylinder threads are stripped.Is there any kind of spray paint that will stand the heat and keep the studs mounted in there fairly good?Any suggestions would be great,because if i were to buy a whole new cylinder top I'd be out another $50 bucks and could have bought a new engine kit.Thanks
     
  2. bseelbach

    bseelbach New Member

    Joined:
    Jul 19, 2009
    Messages:
    136
    Likes Received:
    0
    If you stripped the M6 stud, you can retap the hole to 1/4 20. A stripped M6 hole is almost the perfect size to retap. If you need to run a drill through it first, use a #7.
     
  3. AaronF

    AaronF New Member

    Joined:
    Aug 24, 2009
    Messages:
    389
    Likes Received:
    0
    Thank you for the suggestion.Would the local True Value/Ace Hardware have the thread repairing kits in this size? Could there possibly something else i could try?Thanks
     
  4. Sydneysider

    Sydneysider New Member

    Joined:
    Mar 20, 2009
    Messages:
    189
    Likes Received:
    0
    I agree with bseelbach, I would re-tap it to 1/4 20 its the best way as there is so much vibration at that end it would likely just shake the muffler off.. Good luck
     
  5. bseelbach

    bseelbach New Member

    Joined:
    Jul 19, 2009
    Messages:
    136
    Likes Received:
    0
    You can buy the supplies needed at most hardware stores. 1/4 20 is available at virtually any place. Check Autozone for a tap kit. I think they have small sets (either metric or standard) that come with 3 taps and a handle for $8-9. A small Ace or True Value will run you $10 for a handle and $4/tap. Make sure to buy a tap handle and cutting fluid as well. If you are not mechanically inclined, I would suggest having someone else help you. Go slow, make sure the tap is 90 degrees to the hole and turn the tap 1/4 to 1/2 at a time and then back it off a bit. You want to make sure that the chips come out.

    Your problems will be much, much worse if you break a tap in the hole.
     
  6. GearNut

    GearNut Active Member

    Joined:
    Aug 19, 2009
    Messages:
    5,105
    Likes Received:
    3
    90 degrees to the hole.... eek! :eek:
    Make sure it is straight and true to the origional hole. Not crooked in any way. Go slow with a tap and always keep moderate pressure pushing it into the hole. Do not let the threads it is cutting "pull" it into the hole. That will give you a bad thread cut. Proper tap cutting oil is best, but even WD40 (ugh :() will work in a pinch. As previously said, always turn it in 1/4 to 1/2 turn and then turn it backwards a 1/2 turn to break the newly formed metal chip. If you do not do this the tap will become overwhelmed and snap off in the hole! It is not a fancy drill bit......
    Good luck, and be patient! :)
     
  7. bseelbach

    bseelbach New Member

    Joined:
    Jul 19, 2009
    Messages:
    136
    Likes Received:
    0
    Sorry- meant 90 degrees to the casting........
     
  8. AaronF

    AaronF New Member

    Joined:
    Aug 24, 2009
    Messages:
    389
    Likes Received:
    0
    I called True Value today they have the tap for $7.99 without the handle,Auto Zone has the whole kit for $21.99

    I've got a steady hand that i think a pair of vice/pliers will do the job if i were to go with just the taper...You guys are saying go with the 1/4 20. meaning i would have to get a bigger bolt,couldn't i just re-tap it with the M6 kit?Thanks a bunch guys!
     
  9. bseelbach

    bseelbach New Member

    Joined:
    Jul 19, 2009
    Messages:
    136
    Likes Received:
    0
    This is the autozone set I was talking about. $7 for 5 taps and a handle.

    AutoZone.com | ThreadRepair | 6pcs.SAEtapwrenchset

    If your M6 bots stripped out, the hole does not have enough metal to allow for threads. The threads have pulled out. Options at this point are to 1) fill it and drill and retap to M6 or 2) tap to a larger size such as 1/4 20. Option 2 is much easier.

    Don't try using pliers. It can technically be used but is more difficult. The tap t handle will allow you keep even pressure and keep it straight. Splurge for the tap handle and you will be much happier than the alternative.
     
  10. tyrslider

    tyrslider New Member

    Joined:
    Sep 26, 2008
    Messages:
    958
    Likes Received:
    0
    Actually you can helicoil it using m6 helicoil which requires it to be drilled larger for the insert (stronger than original). Which will allow the same size stud and require no further mods.

    Oh yeah! Don't use anything but a tap handle or you'll ovalize the hole making it weaker!
     
  11. AaronF

    AaronF New Member

    Joined:
    Aug 24, 2009
    Messages:
    389
    Likes Received:
    0
    Option 2 sounds like the route to go for now.If i tap it to 1/4 20.do you know the bolt/stud size for the new 1/4 20?Sorry I'm new to alot of this,I appreciate all the help you guys are giving me.Thanks!

    Also right now i have used loctite liquid on the stud hole inside and on the stud itself its holding damn tight on there but do you think it will last?
     
  12. tyrslider

    tyrslider New Member

    Joined:
    Sep 26, 2008
    Messages:
    958
    Likes Received:
    0
    the threads both male and female are 1/4" diameter 20 threads per inch
     
  13. AaronF

    AaronF New Member

    Joined:
    Aug 24, 2009
    Messages:
    389
    Likes Received:
    0
    I threaded new threads in,now I need to drill a bit through the muffler hole for the bigger stud.So far its going good.Thanks a bunch
     
  14. Reel Adventure

    Reel Adventure New Member

    Joined:
    Jul 1, 2009
    Messages:
    73
    Likes Received:
    0
    Bingo! Thats what I did! It is probably the strongest fix for this problem.
     
  15. AaronF

    AaronF New Member

    Joined:
    Aug 24, 2009
    Messages:
    389
    Likes Received:
    0
    That's basically what i did besides without the helicoil i re-threaded 5/16 and got two bolts in holding it on there very snug.Everything is going good as of now!
     
  16. drhofferber

    drhofferber New Member

    Joined:
    Jun 22, 2008
    Messages:
    307
    Likes Received:
    0
    retap the holes, but dont put studs back in...put allen bolts instead...Dennis
     

Share This Page