Wearing exhaust pipes

Hi All,

Last season I replaced the mufflers on the 850 and commenced riding again now but have noticed a rattle at the clamps between exhaust and muffler. clamps are tight and on closer inspection the exhausts have actually worn down in diameter. I was thinking of trying a pipe/exhaust expander to increase the diameter again , good Idea ? ( and dont say buy new exhausts ! )
Is wear like this common ?

Any suggestions appreciated cheers Hendo .

What kind of clamp?

Sure it is not just over torquing the clamps and squeezing down the overlapped areas?
I use a thin smear of silicone sealant on these joints and just make clamps tight enough to stop any movement.

I,ve seen this before. What length do the pipes enter the silencer? The longer the better, as if they only just go in, the shaking promotes the silencer to waggle about and wear. You might have to extend the pipes by welding on an extension to get an acceptable overlap.

Clamps are the standard ones as sold by andover norton 06.1328

the clamps are pretty tight but as I normally do them and as on other bikes also

unsure of the length they enter the silencer ( not near bike to remove and check ) but the exhausts were original so presume length is correct it's just silencers which are new

cheers

Hendo said:

I was thinking of trying a pipe/exhaust expander to increase the diameter again

Click to expand...

Or, make (and fit) "Beer can" shims/sleeves (actually 0.9mm stainless in the picture below).

I don't use silencer clamps at all
My downpipes extend inside the silencers by around 2"
Never had a problem with wear or cracks

Wear? Or crushed? Or deformed?

Wear would indicate a loose clamp, that has allowed movement, and therefore wear.

Crush would indicate an over tightened clamp that has crushed the pipe.

So, kinda important to work out which of those two it might be, as they’re at opposite ends of the spectrum in terms of root cause.

But… some guys (like Baz) run loose clamps on purpose to allow flex, but I’m not aware of this causing wear. And personally, I find it hard to imagine you could actually crush the exhaust pipe using standard clamps, assuming correct fit and alignment. I’d imagine the clamps would distort or the bolts sheer before that happened.

That leaves the possibility of deformity through poor fit / misalignment. If the silencer and pipe are a poor fit, or are misaligned, and the clamp is forcibly tightened in this situation, then the silencer can dig into the pipe and deform it somewhat.

Or, a PO has used some kind of ‘OTT’ none original clamps of some kind (U bolts as used on cars or similar).

I've it quite often. Most owners don't recognize the signs of movement.

Here is more of "why".

L.A.B. said:

Or, make (and fit) "Beer can" shims/sleeves (actually 0.9mm stainless in the picture below).

Click to expand...

I had same issue and went this route. Worked for me. If you go pipe expander you may risk splitting the pipe if it is worn too thin.

Had the same issue on my RH pipe. Could have sworn that a muffler baffle was loose. Shimmed it with some brass stock I had and problem went away.. I'm inclined to believe that its a result of aftermarket pipes and mufflers from different suppliers with different versions of what's original.

Thanks All,
It is definitely wear,the clamps are tight,
I have thought of shimming the gap .... plenty of beer cans around here !
I recently had the head off to replace the head gasket, and made sure exhausts etc were correctly aligned when installed
Shimming might be the go ..... ?

Concours,
I Liked the brackets attached to the frame in your post ,clever !
My 1970 triumph tiger 650 had a muffler bracket from one side to the other which was perfect on the triumph.....

Mine don't go anywhere near in that length Dan !