soften old exhaust gaskets for reuse

Patton wrote:

Before reinstalling headers, remember to double-check each exhaust port for a second old crushed gasket inside the port, which could be difficult to notice. A dental pick style tool is handy for this inspection...

Too true - they often are so crusted in with carbon, you don't realize they are in the port.

Most of the copper crush gaskets have a flat side and the seam side. The flat side goes in first. I use a smear of gasket goo to hold them in the port.

Related to this, many of the aftermarket pipe companies skimp on the pipes. The lip on the header that the split collars pull against to seal the pipe to the port is often much thinner than stock. If the gap between the exhaust flange and the head disappears to nothing, the pipe will probably not seal or stay sealed. In that case you need to use a thicker exhaust gasket.

MAC pipes are the worst to get to seal. Those thin captive flanges on their pipes will often bend and tempt people to overtighten the nuts (and break studs).

"I use a smear of gasket goo to hold them in the port."

A trick Plum taught me... Permatex Copper... Heat temp plus sealer.... Works every time... I also used this under my aluminum cam end caps thus No Leaky-Leaky...

2nd image... Good stuff!

I am looking for tips on reinstalling the exhaust on my 81 KZ 750. You mention rubber bands on split collars, is there a certain orientation the gaps must go? having a heck of a time sealing. Believe they are the stock 4 to 1 pipes. Replaced the starter clutch through the oil pan and now cannot get pipes on correctly. Any help greatly appreciated!

Stock pipes are 4-2.

I use wheel bearing grease to stick the new gaskets into the exhaust ports - be sure any old ones aren't left in the ports.

Empty boxes & bungee cords are handy for holding the exhaust system in position.

Make sure any muffler or exhaust clamp bolts under the bike aren't oriented in the wrong direction, causing interference.

I don't use rubber bands on the half-moon collars - I just hold them in position then slide the exhaust holders in place w the splits half-way between the mounting studs.

Hand tighten the nuts, then move on to the next one. Be sure to mount the muffler before tightening down the exhaust holder nuts.

I don't know if it's the right way but I use masking tape around the collars to hold them and I put them so that the seams are 90 degrees from the exhaust stud.

MAC pipes are the worst to get to seal. Those thin captive flanges on their pipes will often bend and tempt people to overtighten the nuts (and break studs).

Guilty of that one. Thankfully it was an outside stud on my Twin so I didn't have to much trouble drilling it out and replacing it.

run an open header and you won't hear the leaks. :evil:

Yeah, Jeff is right. I'm noticing posts about Jimmy Rigging left and right. I think that in the long run cheap fixes end up costing much more. Is there any one on this website that isn't in to red-neck engineering????? I can totally hear Jeremy Clarkson and his comments about americans. I love his show but think he smokes poles with that comment until I read all these posts on here.
I love these old bike but dang!!!!! Get er dun. But get her done right! All the talk about reusing this that and the other. Car muffler silencers Jimmy rigged to work in the place of baffles. The kz gods would be sending the lot of you all to hell for the rat bikes that you so neglect. If you wait the oil from the blow by will exit the flanges and slowly seal the leaks.
I say! Can't most of you guys appreciate your old classics and care to do them right?!?!?! So many guys on this forum really make me cringe at some of the so called rebuilt or improved upon ideas that add up to rat mechanics. Give me a break. Surely no one in Europe that is on this site would agree with the atrocities that occur on a daily basis here. Shite man, if you can't afford to do things right then buy a crappy Yamaha or Honda or better yet a Suzuki and please sell your bikes to collectors over seas so to insure a proper restoration to your beloved Kz900/1000's or z1's.
At least one of the members had enough sense to sell his bike for big money because he knew he couldn't give her the proper resto she deserved. Too many of you guys approach ridiculous with your back yard restos. I wanna puke when I see what everyone thinks is a great looking bike that looks like something the dog chewed up and spit out. If you can't afford a simple thing maybe a newer bike would suit you better. I just bought a bangin zrx1200 with 7200 miles and over 2k in make nice parts on her for 2900. Heck the gears and crank on my bike cost more than that. But she screams and at a basement bargain price. Guaranteed cheaper than buying an old kz and crapping her out and then later trying to breathe life in to her.


Sooooorrrryyy for the rants and raves but it seems like everyone who doesn't care to do things right or care for things is trying to do the two cent resto. If you ain't got it to do it right then pass her down the line to someone else.:S

So apparently you feel that only those with means should have the right to enjoy these great machines. Or that the only "right" thing for these machines is to restore them. Yet if your avatar is a pic of your bike it appears that it does not have a stock exhaust on it - why is that, could you not do the right thing and return it to its correct state.

Look all of us enjoy these machines or we wouldn't have them. I thought this forum was a place to share, learn and discuss these machines. But just cause some do not meet your idea of what is right, or do not treat their machines as you think they should does not mean they have any less right to enjoy them as you do.

gd4now wrote:

So apparently you feel that only those with means should have the right to enjoy these great machines.




I don't think he said that at all. I think to be more to the point is to say It's $8 worth of gaskets ya cheap bastid, skip lunch today and buy the gawddamn things!:woohoo:

I get the part about the gaskets, but saxjonz spoke about much more that the gaskets. His post was more about how unless you can do things right - what ever that maybe - you should not have the bike. He pointed out that the costs of his crank and gears were more that a newer bike he has purchased. To me that is saying if you can not or will spend $$$$$ on one of these machnes then you should pass it onto someone else. Which I just do not agree with.

Saxjonz has a point there...he's just forgetting that some of us got into bikes from watching Mad Max too many times instead of hanging out at the Dealership.

saxjonz wrote:

Yeah, Jeff is right. I'm noticing posts about Jimmy Rigging left and right. I think that in the long run cheap fixes end up costing much more. Is there any one on this website that isn't in to red-neck engineering????? I can totally hear Jeremy Clarkson and his comments about americans. I love his show but think he smokes poles with that comment until I read all these posts on here.
I love these old bike but dang!!!!! Get er dun. But get her done right! All the talk about reusing this that and the other. Car muffler silencers Jimmy rigged to work in the place of baffles. The kz gods would be sending the lot of you all to hell for the rat bikes that you so neglect. If you wait the oil from the blow by will exit the flanges and slowly seal the leaks.
I say! Can't most of you guys appreciate your old classics and care to do them right?!?!?! So many guys on this forum really make me cringe at some of the so called rebuilt or improved upon ideas that add up to rat mechanics. Give me a break. Surely no one in Europe that is on this site would agree with the atrocities that occur on a daily basis here. Shite man, if you can't afford to do things right then buy a crappy Yamaha or Honda or better yet a Suzuki and please sell your bikes to collectors over seas so to insure a proper restoration to your beloved Kz900/1000's or z1's.
At least one of the members had enough sense to sell his bike for big money because he knew he couldn't give her the proper resto she deserved. Too many of you guys approach ridiculous with your back yard restos. I wanna puke when I see what everyone thinks is a great looking bike that looks like something the dog chewed up and spit out. If you can't afford a simple thing maybe a newer bike would suit you better. I just bought a bangin zrx1200 with 7200 miles and over 2k in make nice parts on her for 2900. Heck the gears and crank on my bike cost more than that. But she screams and at a basement bargain price. Guaranteed cheaper than buying an old kz and crapping her out and then later trying to breathe life in to her.


Sooooorrrryyy for the rants and raves but it seems like everyone who doesn't care to do things right or care for things is trying to do the two cent resto. If you ain't got it to do it right then pass her down the line to someone else.:S

I think many will disagree with you on the whole redneck engineering deal. There are MANY members here that are very talented mechanics, machinists, fabricators and riders that don't deserve to be pissed on by your lame generalizations.

If a guy wants to turn his Z1 900 into a chopper, or a rat bike well that's his decision now isn't it? It's his (or her) money and that person has the right to express themselves mechanically any damned way he or she pleases. You shoot your mouth off about how people are "desecrating" these old bikes like they were some kind of priceless artifacts. When it's all said and done, they are JUST motorcycles. I love the classics as much or more than anyone, but I'll never put them on a pedestal above all others.

Lighten up Francis.