Exhaust gasket recommendations???

Joined
Dec 19, 2004
Messages
413
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Hello Everyone,
I've had alittle trouble with my exhaust pipes loosening up this year, NOT the exhaust nut, that stays tight. I pulled the right pipe today to find the crush gasket flat as a pancake (actually much flatter). I replaced it with a copper ring type from a Honda CB750. It seemed to fit well and tightened up, but, after a twenty mile ride the pipe (not the nut) was loose again, I suppose that the normal engine shaking had compressed the gasket some more and that I will be able to retighten the nut. But I thought I'd ask if anyone has found one type of gasket to be better than another, Norton, aftermarket, or alternative???

insights appreciated,
G.B.
 

TT

Joined
Mar 7, 2005
Messages
53
My right header has the same problem. It loosens over time when the crush gasket compresses - but the exhaust nut is tight.

I suspect that my right header is slightly bent from a previous 'off'. The muffler backets at the back of the bike were also bent. These are the only other support the exhaust system has. While it looks great and hides most of the ugly bits the system is very prone to vibration and leverage.

I have heard of using 2 crush washers but I have never tried it.

Are the CB750 washers the same diameter and thickness?
 
Joined
Mar 19, 2005
Messages
696
I think you will find that this problem,(nut tight, but pipe loose), is the result of years of riding with the nut sometimes not tight enough. If the nut has been not tight enough, for long/often enough, then the INSIDE surface of the exhaust port, where the gasket seats, gets dished out from rubbing back and forth with the pipe wiggling (it's only aluminum, after all),and since the nut can only go SO far into the head, due to the depth of the threads, tightening up the nut will not solve the problem, it's the head that is damaged. The gasket will compress to a given thickness, and since the nut has reached it's deepest point(and is tight), the wear in the inside of the hole in the exhaust port will see that even a relatively new gasket will let the pipe get loose in a short time. Not much to do at his point but make the threads deeper (not feasable), put a washer on the pipe, between the nut and the surface the nut seats against (but that would have to be a very big washer, with a very thin profile to fit in the exhaust port...forget it), or, what is the easiest, put two gaskets in the exhaust port and this time keep the nut tight.

Mine has this problem on one side, and I have to do the 2 gasket thing, but it at least lets you get the nut tight and the pipe won't wiggle and vibrate around, and destroy the threads. I safety wire the exhaust nut to the valve cover nut, to make sure it doesn't get loose. Two gaskets will seal well enough to get the job done........
 

TT

Joined
Mar 7, 2005
Messages
53
The 2 gasket method is a success... I see the need for lock wiring now. The exhaust locking ring is loose and rattles around.

The 'kickstart lever hitting the muffler' problem is also fixed. I bought a new pre-Mk III kickstarter crank - it clears the muffler by 1/2 inch. I was amazed that the old kickstart crank was so out of shape.
 
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