Author Topic: Exhausts  (Read 1556 times)

Offline Tone

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Exhausts
« on: 07.04. 2009 20:37 »
Guys, What are your thoughts on using jointing compound between the pipe and head?

Offline beezalex

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Re: Exhausts
« Reply #1 on: 07.04. 2009 20:48 »
I use something here that's called "Muffler mender".  It's a water-based paste that turns into a hard ceramic-like substance.  I have found, however, that unless the pipe is a tight fit in the head, no amount of goop holds for very long.  I use a tailpipe expander to make the pipe fit.

Hope that helps.
Alex

Too many BSA's


Offline snowbeard

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Re: Exhausts
« Reply #2 on: 08.04. 2009 19:51 »
you guys are really going to start laughing at me now, but I'll admit to yet another bodge I use.   *eek*

my headers are old and slightly rounded on the ends, from many years of maintanance I expect. it kindof helps getting them on and off, and I've tweaked the mounts to hold them pretty tight by now.

still, they leak around the header, so what I've found works pretty well is aluminum foil duct tape!  I take a strip long enough to wrap around the header once, then fold it up longways to make multiple layers (also hiding the sticky side inside itself) the end product being about a 1/4 inch wide and maybe five to eight layers thick.  I then flatten this with a roller or spoon or whatever is handy to be super thin. 

I loosen the heat dissipating flange, pull it back and wrap the flat strip around the header. I gently stuff this flat bit of aluminum into the crevice around the header into the exhaust hole.  it doesn't go all the way in, and leaves about half the width still out.  then I slide the flange up against that and gently go round it with a wood dowel and light hammer, tapping the flange against the foil, compressing it into and around the header. then tighten down the flange.

I've redone this a couple of times so far and it actually makes a great seal, and is totally removable as well as not adding a bunch of stress on the head exhaust port!  being a light aluminum it molds well to the crevices, doesn't burn up, and really made a difference on my bike.  I could hear the exhaust hissing out the headers before I did this, but after it was silent and even in the cold I can't see the puffs of exhaust I used to!

ok, once you stop rolling on the floor, you can tell me what a dolt I am... *red*

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Offline BSA_54A10

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Re: Exhausts
« Reply #3 on: 09.04. 2009 00:15 »
Lead or any lead based alloys would melt.
Off the top of the head ( which means that is is going to be wrong ) the straw colour on the pipes is about 250 deg and the blue is 450 deg way above the melting point of solder.
Bike Beesa
Trevor
Bike Beesa
Trevor

Offline snowbeard

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Re: Exhausts
« Reply #4 on: 09.04. 2009 00:26 »
right, solder was my first thought too, but I'm pretty sure that it would melt.  that, and I didn't want to do anything that would be permanently adhered to either surface that I'd have to chip off when I pulled it apart again...
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Offline tombeau

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Re: Exhausts
« Reply #5 on: 09.04. 2009 06:40 »
Sounds like a good tip Snowbeard. I'll give it a try.
My friends here swear by silicone gasket sealant. I was doubtful that it would handle the heat. It worked on one pipe but not the other. That could have been down to me not getting the pipe clean enough though.
Cheers,
Iain

Offline LJ.

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Re: Exhausts
« Reply #6 on: 09.04. 2009 09:33 »
Quote
It worked on one pipe but not the other.

Ahhh! Your suffering from Induction Bias Iain!

 *smile*  *lol*
Ride Safely Lads! LJ.
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1953 BSA B33  500cc Teles/Plunger-Maroon
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Re: Exhausts
« Reply #7 on: 09.04. 2009 12:45 »
You could always try Firegum, which works pretty well for me on bikes with twin pipes but less well on the lh head of Siamese pipes, which just seem to want to wriggle out over time for lack of proper positive location. At least it's made specifically to withstand exhaust temperatures.
Bill

Offline tombeau

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Re: Exhausts
« Reply #8 on: 09.04. 2009 12:56 »
You're right LJ I am!
Cheers,
Iain

Offline BSA_54A10

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Re: Exhausts
« Reply #9 on: 09.04. 2009 14:11 »
Or you could buy some "Lagging" tape or more rather "lagging string"
Should be able to get it from Sears on line
Or there is a high temperature silicone.
Sears again
Or a high temperature "O" ring.
Probably from Aircraft Spruce.
Bike Beesa
Trevor