Muffler gaskets

Hi,
I recently replaced the mufflers on my 1979 KZ650D with what are actually the originals (or an original set). The ones that were on were modified or after market and came with the bike.

I did Not replace the gaskets as I thought I didn't need to, but now there is a rattling noise that at first came after the bike got hot, but now comes whenever it's warm (after a minute or two of running). I was told it may be the timing chain but I want to replace the gaskets first to see if that fixes the problem.

How do I remove the old gaskets? Either they weren't there when i changed the mufflers or they are quite mashed in and very hard to remove. Do I use some kind of metal pic tool?

Welcome to KZRider.

There are two gaskets on the exhaust system. One is a copper washer that fits inside the exhaust port on the head; the other seals the muffler to the header pipe and is shaped like a small piece of round pipe, about 1-1/2" long and 1-1/4" diameter.
Which part are you talking about?

The copper washer gasket is available from Z1Enterprises

The other gasket may be found at Z1, you should ask them. Or check the dealer or Ebay.

The rattling noise may be the cam chain, it is very easy to adjust. If you don't have a manual yet look on KZRider classifieds or ebay.

Thanks for the quick response!

The copper washer is what I was talking about. Is it possible that there wasn't one inside from the other mufflers? Or is it hard to get out. I pick at the edge a bit and there didn't seem to be too much give, but it was covered in carbon and so hard to tell by looking.

They do get hidden by the carbon, and they can be hard to get out. It certainly is possible there are none in there.
If you have a real pick (not a screwdriver) you may be able to pop it out of there if it's in there.

You can locate an unknown noise with a long screwdriver; hold the blade on the engine while putting your ear to the handle.

Tell us more about your bike, what model is it, miles, general condition, latest repairs or service, etc. Add the model to your signature block in your profile.

And we love pictures!

thanks alot for the tip about the screwdriver-noise-finder!!

if you took off some type of header, and put a stock set back on, I think you need to look at rejetting the carbs, they maight be way rich,
also if the carbs are out of sync, you can get a cam chain type of noise this may also be from the header removal

thanks again. How do I know if the carbs are rich?

The best way to tell if carbs are rich is to get her back together and start it. Do a "plug chop". Search archives or internet with that term, but basically throw in some new plugs, ride it wide open throttle in 3rd or 4th gear for a mile, hit the kill switch, pull in the clutch, close the throttle (do this all at the same time) and coast to a stop. Pull out the plugs and see if they are black, tan or white. Black means rich, tan is perfect, white is lean.

Welcome to KZr robmaci.

I'm wondering, when you replaced the exhaust with an "original" set, did you install the exhaust collars (ref #2 in pic below) AND get them aligned and snugged up properly before tightening the nuts onto the exhaust studs?


It's possible that is where the "rattling" sound you described is coming from - it can't hurt to check just to be sure.

Yeah, I think I did do that. I remember the Clymer saying that everything should be fit and then screwed in hand tight before tightening the nuts.
I'll check this all out tomorrow though. Thanks alot for this. I'm surprised at how helpful you are!

Wellcome Rob.OKC is right about the plug chop thing.Just check your plugs first.If they are black and sooty you are too rich tan is good.The problem with doing the chop test with new plugs is the gas today dosnt colour as fast as the old gas.You will need to put several miles on new plugs to get a reading.I would cruse at 1/2 throtle for about 5 miles on the highway then do the plug chop and relace the plug with another to get home.Then when you get home cut the threads off the plug and look at the base of the insulator for a tan color.Since you only ran at 1/2 throtle this test will only tell you if your needle is at the right hieght.If its too rich (black color)you would lower the needle by raising the clip 1 notch.Then retest.The hard part is the full throttle test.Since you need to hold the trottle at full for 5 miles you will run out of rpm and must cut the throtle and egnition and redo this test several times to get 5 miles on the plug,then you will change your main jet acorrdingly.You realy should do the full throttle first then the 1/2 but this way you can practice safley at 1/2 .
Anyone else have first hand experience with this?

Thanks to all for the help with this.
I ended up bringing the bike into a shop and they found it was the tensioner which was worn down making the rattling noise. Took a very long time to get the part from Kawasaki but now all is good.