Author Topic: Sealing the system  (Read 389 times)

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Offline steve

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Sealing the system
« on: June 15, 2020, 09:27:46 am »
Any ideas on how to seal the header to muffler on a 1976 CB750A?  I cannot find the gasket anywhere. 

Thanks in advance for any ideas.

Offline sammon287

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Re: Sealing the system
« Reply #1 on: June 18, 2020, 10:13:05 am »
I just did this on my '76 A by wrapping a whole roll of high temp flue tape around the circumference of the header. It seems like it will work, although I have not run it yet. I'm close to the end of a very slow restoration and covid-19 stalled my progress. The proper graphite gasket is available from Europe for $$, but I really think this will work for $8. I could not find a gasket meant for another model that was the right size.

https://www.amazon.com/3M-High-Temperature-Flue-15-Foot/dp/B00004Z4DS/ref=asc_df_B00004Z4DS/?tag=hyprod-20&linkCode=df0&hvadid=167116234959&hvpos=&hvnetw=g&hvrand=11556441530423727576&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9006780&hvtargid=pla-313874637779&psc=1
1976 CB750A

Offline Alan F.

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Re: Sealing the system
« Reply #2 on: June 18, 2020, 11:07:59 am »
Edit: is flue tape the same product?

I wonder if you could use the type of aluminum sealing tape that's used on clothes dryer vent ducting?

https://www.google.com/search?q=clothes+dryer+vent+tape&oq=clothes+dryer+vent+tape&aqs=chrome..69i57.9487j0j7&client=ms-android-verizon&sourceid=chrome-mobile&ie=UTF-8#scso=_x6vrXu3NGKXJ1QHh5L2IAw69:0

Also search for the high temperature variety which seems to handle temps up to 600F, but of course price reflects that.

Offline sammon287

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Re: Sealing the system
« Reply #3 on: June 18, 2020, 01:52:02 pm »
The kind I linked to is the high temp 600 degree kind and is the same brand (3M) that I used. I took some measurements and it ends up at just the right thickness when the roll is expended.
1976 CB750A

Offline Alan F.

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Re: Sealing the system
« Reply #4 on: June 18, 2020, 02:07:59 pm »
That's a great price too, much lower than the factory bushings would cost.

Could you update this thread after you've been riding a little?

Offline sammon287

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Re: Sealing the system
« Reply #5 on: July 10, 2020, 07:43:10 am »
After a two year long engine rebuild, I finally started it up the other day. I ran it twice so far and the fresh engine paint was smoking slightly, but the 600 degree flue tape gasket seems to work swimmingly. No exhaust leaking and no fire. I know that portion of the exhaust was plenty hot, since I burned my leg trying to reach over the bike to shift into gear with my hand while it was on the center stand. My header is ceramic powder coated, so it might be putting a little extra heat downstream than chrome plated pipes. 
1976 CB750A

Offline Alan F.

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Re: Sealing the system
« Reply #6 on: July 10, 2020, 09:13:16 am »
That's great news, sorry to hear about the burn. Heal fast!