Exhaust Header Nut and Shim Question

Marc Douglas

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Hey Guys, new member here!

I've been digging around the forums, but I can't find the answer to my exact question. I recently completed my first build (which is incidentally my first bike ever) and I'm running into a potential issue with my exhaust headers.

I reused my old exhausts and purchased a lightly used set of shims (serial # confirmed) when reinstalling them. After wrapping and reassembling, there's about a 1" gap between between the large nut and the header itself. I also have a new crush washer installed as well.

Is this gap normal, or should the nut be relatively flush with the header? I'm looking to avoid potentially breaking/shearing the header bolts, but I don't know how much the shims need to be crushed in place. Thanks in advance!
 
Here's a picture of what I'm referring to:
 

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The carbs are the tuned Mikuni TM32's from MikesXS and the baffles are Emgo 15" slash cuts. I was thinking it might be a back pressure issue.
 
Lots of things can cause the problem you have. If yours has points make sure they are both set correcty.
Make sure the timing is correct and the advance works. After you make sure all that is correct, tuned carbs are often too lean.
 
Did you change everything all at once? Hard to narrow it down. Maybe put it back to stock and make sure it runs well, then make changes one at a time. When things get bad that’s your culprit.
 
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