Any Suggestions for this Exhaust Leak?

Hi there.

I will be looking into a new exhaust system for my 81 KZ750-E2 next year, but in the meantime I am stuck with an ill-fitting header that leaks.

It is the type that uses a collar bolted to the engine and then the pipes are held in by springs (see image).



The exhaust leaks around the pipe itself, as the collars seem to seal up pretty well to the engine with new crush gaskets in there.

Any suggestions on how to seal these up? Should I fill the gap with some sort of sealant, or should I pack some sort of insulation into the cracks?

Thanks for looking.

You could try cleaning all the carbon off of both mating surfaces, then smear some High Temp Copper Permatex Silicone around the joints, put it together, wipe off the excess and let it cure 24 hrs. Then run it.
www.all-spec.com/products/81878.html?gcl...mvurkCFShxQgod1G8A8A

What kind of headers are those? It's a pretty common set up on a race bike but the "overlap" goes the other way.

I have no idea! They were on the bike when I got them. There has been some welding and modifications on them, so they may be home made.

I will try some of that high temp sealer and see how that goes.

Maybe try thicker exhaust gaskets?

These are a little larger in diameter than stock, but I think they will work. not sure.
Z1Enterprises.com - Suzuki exhaust gaskets - Emgo EM13-87851-1

Or maybe these? ... slightly smaller in diameter.
Z1Enterprises.com - Yamaha exhaust gaskets - K&L KL16-0180-1

I agree with martin csr .GS gaskets seem to work nice somewhat thicker, tighten snug evenly warm up bike and recheck.Permatex helps as well.

weld that sucker up....

4TheKZ1000 wrote: weld that sucker up....

Yes that would solve that slip fit permanently. Then you could get some of the thicker gaskets also.

Welding may be the way to go. I will have to bring the bike to someone to tack the collar in place before I take them off (to ensure the collars are sitting flush with the engine). I will look for those gaskets as well.

In the mean time, I will try out the sealant mentioned earlier.

Thanks for the ideas.

Before you weld up the spigots to the pipe. Make sure you can get to your oil filter, if not you will have to remove pipe every time you change oil and filter!!!

I would remove pipe and spigots, clean all the carbon off of pipe and on the spigots where the pipe slides into it. Put the spigots back on the head with factory copper style exhaust gaskets Then try the hi-heat silicone to seal pipe to the spigots. Do the springs still apply enough tension to hold the pipe tightly against the spigots?? I always used some exhaust springs from a early model KX125 on my Bassani pipes.

Do I see little holes drilled into the nuts holding your exhaust spigots to your head?? The previous owner was either very safety conscious or a road racer!!!

Is there a "shoulder" inside the collar that might accept an exhaust gasket between the pipe and collar?

The hole in the nut is a trick of the camera. There are no safety wire holes there. Doesn't mean it wasn't raced, but the PO wasn't very safety conscious if it was!

There are small shoulders inside the collar, but I am unsure if the pipes sit tight against them. It is worth a look. The springs I have are not that tight, so I will see what I can find.

The person I know that will weld them isn't available for some time, so I will be trying some sealant in the meantime. You can get to the oil plug with the pipe in place, so that is a good thing.

Unfortunately, the system doesn't allow me to use the centre stand. Any new exhaust I buy will accommodate the stand. I think the Vance and Hines 4 into 1 allows the centre stand to be attached. I will need to look into that.

Thanks again for the additional suggestions. I will be working on it this week sometime.

Peter