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Discussion Starter #1
my after market exhaust bolts constantly rattle loose, i had to rethread bolt holes on motor and i think when i rethreaded it i weakened it.
 

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There might be a high temp thread sealer. I wonder if Teflon thread tape would work.
 

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Most small Chinese engines use a flange system to where you can drill the threads out and use longer bolts and back it all up with plain old hex nuts....

On some cylinders you can use a file to modify the flange to fit a nut....

Sometimes the nuts or even the washers only have to be modified with a file but it's better than rattling loose..

That's what I do .......

Good Luck
 

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Discussion Starter #6
ill look and see if i got that flange i just dont want to drill through anything important
 

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Discussion Starter #8
ill send pics, do i need some kind of spring type support for muffler and the vibration?
 

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Discussion Starter #10
here is the pictures, that is the gasket i bought, and the support for exhaust and where i want to put it
 

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dammmm man... thats ... so its time to tap and high heat epoxy studs in there then you need to grind that flange flat where the nuts will sit when you cinch it down i recommend 1 two finger ogga dooga or about 10 to 12 inch lbs with some lock tight
 

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where did you get it ? thats a bike exhaust flange (and system) its just a tiny bit to small to fit that engine on the flang and well.... your going to need to fix that befor you do anything.... way to restrictive for that engine
 

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Take two helicoil and repair the threads, then insert two bolts, no screws. And you should make you an holder for the exhaust, when the exhaust isn't fixed to the frame, then there is always the whole weight on the two screws.
 

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Take two helicoil and repair the threads, then insert two bolts, no screws. And you should make you an holder for the exhaust, when the exhaust isn't fixed to the frame, then there is always the whole weight on the two screws.
to do helicoils wiuld require him to drill and tap to the next size....


Why wouldnt he just use a larger bolt with a round socket head and save making a bunch of slinkys out of a package of heli-coils...?
 

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you have a motorized bike setup... this is why the flange wont line up and the header tube size is smaller then the exhaust port on your engine ...

The poorly designed bicycle engine needs a lot of back pressure to hold the mix in the cylinder so it can run ( if that's what you want to call it more like sputtering across town)

50 / 80cc Bike Gas Engine Motor Parts - Voodoo Pipe Exhaust Muffler Black

https://www.ebay.com/p/50-80cc-Bike-Gas-Engine-Motor-Parts-Voodoo-Pipe-Exhaust-Muffler-Black/19004854975?iid=142438667781&chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=142438667781&targetid=538495503055&device=m&mktype=pla&googleloc=1016140&poi=&campaignid=6470544939&mkgroupid=81274457887&rlsatarget=pla-538495503055&abcId=1139336&merchantid=113776281&gclid=Cj0KCQjwzozsBRCNARIsAEM9kBPT9sHLB0FaK0cQG1leec2VA3Hb5t0Xsay7xA4KH4Mzdnai8UkdA7EaAsk4EALw_wcB
 

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He would get way better performance gutting and reinstalling the box muffler than using that waste of $$$
exhaust pipe...
 

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i agree gutting the stock box and a tune will give him the most performance out of basicly any other options.

i love the add for that pipe saying it gives 3000 RPM increase ROTFLMAO they must be takeing notes from the china car audio manufacturers where you just add a zero to the real numbers try 300 RPM maybe on a good day 200$ for that trash wow...

the aftermarket box type is cool i bet $ the internal dimensions are the same as the stock muff box with the baffle removed so your paying 100$ for bling
 
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