Small exhaust leak: try to fix it or leave well enough alone?

Just installed the Scorpion and noticed there's a tiny bit of a leak at both the mid-pipe to can and mid-pipe to header joints. If I put my hand close to the pipe , it feels like very light wind.

What do you think? Try to fix it with exhaust sealant (or something else) or just leave it alone?
 
I have the same situation now with the Arrow headers. It *mostly* seals itself with heat expansion but not fully. I'm waiting until the season is done and then will take off all of the exhaust and start from the front and work backwards until I've sealed all of the joints. For now, I just let it be.

Ironically, the Two Bros IS sealed to the Arrow but when it was on the stock header, I had the same leak. Now, it doesn't leak there at all but the header parts themselves have leaks.
 
I have the same situation now with the Arrow headers. It *mostly* seals itself with heat expansion but not fully. I'm waiting until the season is done and then will take off all of the exhaust and start from the front and work backwards until I've sealed all of the joints. For now, I just let it be.

Ironically, the Two Bros IS sealed to the Arrow but when it was on the stock header, I had the same leak. Now, it doesn't leak there at all but the header parts themselves have leaks.

Interesting. So when you say "seal", do you mean using sealant? The blue stuff?
 
Interesting. So when you say "seal", do you mean using sealant? The blue stuff?

The best stuff on the market is the Ultra Copper. Typically less than $10 a tube. On their site, when you select the motorcycle tab for the product, it states the following:
Suggested Applications: Exhaust header flanges, slip fit exhaust pipes, and muffler end caps - See more at: http://www.permatex.com/products-2/...cone-gasket-maker-detail#sthash.y6QscZxd.dpuf

WP599192.jpg
 
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Hmm.. Ultra Copper seems to be geared more towards gasket applications (using it instead of paper gaskets, etc).

This stuff seems to be what *should* do the trick: Amazon.com: Permatex 80335 Muffler and Tailpipe Sealer, 3 oz.: Automotive

I guess it's how you view the issue and resolution? I believe both will work great actually.

I see my issue as a leak because there are no gaskets at the slip-fittings so I'd use the Ultra Copper to create that and fill the gaps. I think the sealer will accomplish the same goal though. Their site just doesn't list motorcycles as an application for it. Also Arrow shipped the headers with a very small pouch of Ultra Copper, but it wasn't nearly enough. ;)
 
Save your money and put some plumbers tape around the areas that need it.
It seals it up and it doesn't burn.
It's an old racers trick that works well.

Sent from my GT-I9300
 
My uncles sled has custom built twin pipes they dont have any type of gaskets. I use ultra copper. The exhaust gasses are over 1000* most of the time. It holds up very well even to the excess oil the 2 stroke dumps by it.
 
How would you apply UC? Videos show that it's applied like any other liquid gasket. In case of exhaust, do you apply it like grease to header end and slide mid-pipe over it?
 
We use UC all the time on exhaust joints in our workshop. Just a light smear then slip the pipe on. is really good on car flange joints & is high temp.
 
Nice. I agree with the plumbers tape comment. I actually have heard of people doing that in the past.
I think the UC application is a little more complicated than what I want to get into at this time.
 
What exactly is plumbers tape? Teflon Tape? Something else?

I want to fix exhaust leaks in my 2004 Yamaha FZ1, as the exhaust sound is too loud.
The leaks are in the joints not through any holes in my pipes.
I was going to use Ultra Copper but I have a question about its properties. If I find some problem with the work I did, how hard is it to take the exhaust apart and reapply the Ultra Copper?
I asked this question of Permatex Customer Support and received the following answer...
You will need to cut away the Ultra copper and try to loosen the joints if you need to disassemble in the future. Cured silicone is. difficult to remove.
Does anyone have any experience with taking apart joints glued together with Ultra Copper?

So I would like to do it first with Plumbers Tape.
 
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