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Finally living my dream
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Discussion Starter · #1 ·
Hey everyone, I'm having a problem with the baffels on my Samson's coming lose and rattling. There's a bolt that goes through the side wall of the pipe and through the baffel held on with a nut. Well the nut keeps coming lose or falling off all together. I've tried everything I can think of. What I've discovered is happening is that the bolt is actuall stretching, presumably when it heats up under riding conditions. That apparently allows the nut to fall loose even with thread lock (which probably melts in the heat).

So anyway here's my question. Does anyone know if higher grade bolts would be more resistive to deforming under heat? The bolt that was in there was a Grade 2, so pretty soft. I just tried using a Grade 8 nut and bolt, so I'll have to see if that works. Just curious if my theory that using a higher grade bolt would help, actually makes any sense.
 

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Livin the dream
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I would use a pinched locknut with the grade 8. Its the semi deformed type nut that pretty much screws up the threads when put on but comes off just as tough as it went on. Ive never heard of a grade 2 (doesnt mean there isnt such a thing) but grade 5 has the 3 lines on the head and the 8 has 5 usually. Unless its metric then they have numbers.
 

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You need those nuts with the star pattern washer already fixed to them.........they never come loose.

I run 3/16 S/Steel Butten heads with the above type nuts with the washer attached.

All the best, Ozzie
 

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Grade 8 steel

Grade 8 bolts are hardened steel way harder than your pipes mild steel. One thing to keep in mind when using Grade 8 hardware on any application is the hardness of the metal you are using the bolt to fasten. Wouldn't want those Grade 8's to wear out your pipes or baffles like they were made of paper.
 

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Finally living my dream
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Discussion Starter · #5 ·
Thanks for the responses guys. As far as Grade 2, it's also commonly referred to as 370A (basically a bolt marked 370A or having no markings on the head at all). Installing the bolt I didn't run into any issues with the difference in hardness between it and the pipes. Since the only stress put on the bolt is from the nut, I don't expect that having a hardened bolt in regular carbon steel is going to be an issue (but it was a good point nonetheless).

So far the bolt is holding tight, I'll have to see how it looks a month from now. If it holds its shape I should be good. I didn't think about a pinched lock nut (I assume you're referring to the type with the threads that get narrower) however other locking types (like the star washers) have not worked so far because the bolt stretches to the point that the star isn't making sufficient contact.

Thanks for the ideas guys, I'll let you know how things go.

:cheers:
 

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Finally living my dream
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220 Posts
Discussion Starter · #6 ·
Well two weeks later and things look good. The bolt hasn't deformed at all and is still holding tight. No issues with the pipes at this point. Gotta watch it a little longer but hopefully I'm in good shape. Thanks again guys.
 
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