'81 Kz650 exhaust crossover nipple broke

PLUMMEN wrote:

id clean up around it with some sand paper and maybe smear a little clear silicone around it to seal it up

Is there a high-temp silicone available? I have never looked for it, not being aware of it, would I find it at an auto parts store?

I was thinking of using some metal tape, the expensive kind that is super-sticky and is using on water heater vent pipes -- I have some laying around from various water heater rehabs.

However when I put my hand around the repair I don't feel any leak.

The other thing I noticed after a longish ride today was -- a color change.

The photo above showing the system all put back together was taken before riding.


After I got back -- the copper color had changed. It is much less reddish -- it looks like brass in color, I guess after all the heat.


That makes me wonder -- since this copper piece was designed only for the heat of hot water in a house -- I wonder how the repair will hold up over time.

The sandpaper was a good suggestion. I was in such a hurry to find out if my problem was solved I rushed into it. Will get to it next time the exhaust comes off.

That's a great fix for just a couple bucks! My hat is off to you. Ed

650ed wrote:

That's a great fix for just a couple bucks! My hat is off to you. Ed

Thanks dude, I called in some good karma on this one.

I have another Kz650, it is a 1979 'SR' Kz650, that I bought prior to this one, and I bought this one because the '79 was not going as planned, it feels good to be riding again. I have another superbike (Z1) but it is a real strong machine and at my age a bit too much power, its a great highway bike but California drivers are nuts.

This 650 size seems real good. If I could just cut some luck with my SR life would be good. Tomorrow I'm gonna check the SR to see if my atf+acetone has worked its way down to free up the stuck pistons. The '79 SR 650 has been setting for over 2 weeks now and at the time I put it on the back burner I filled the crankase up with oil, now its got lots of lubricant on top the pistons and below, I hope the motor is freed up.

newOld_kz1000 wrote:

PLUMMEN wrote:

id clean up around it with some sand paper and maybe smear a little clear silicone around it to seal it up

Is there a high-temp silicone available? I have never looked for it, not being aware of it, would I find it at an auto parts store?

I was thinking of using some metal tape, the expensive kind that is super-sticky and is using on water heater vent pipes -- I have some laying around from various water heater rehabs.

However when I put my hand around the repair I don't feel any leak.

The other thing I noticed after a longish ride today was -- a color change.

The photo above showing the system all put back together was taken before riding.


After I got back -- the copper color had changed. It is much less reddish -- it looks like brass in color, I guess after all the heat.


That makes me wonder -- since this copper piece was designed only for the heat of hot water in a house -- I wonder how the repair will hold up over time.

The sandpaper was a good suggestion. I was in such a hurry to find out if my problem was solved I rushed into it. Will get to it next time the exhaust comes off.

any 100% silicone should work B)copper can hold up to an acetylene torch,i dont exhuast temps will hurt it.
your exhuast gast are copper also,biggest thing id worry about with that fitting is corrosion from stuff on rod kicking up there

Patton wrote:

High temp silicon -- thanks Patton, I will have to pick some up -- I just hope my copper re-pipe holds, time will tell. It says 'gasket maker' so that means it holds up to cylinder-level heat, should be find for the crossover tube level of heat.


Thanks everyone for the help on this one.

-

newOld_kz1000 wrote:

Patton wrote:

High temp silicon -- thanks Patton, I will have to pick some up -- I just hope my copper re-pipe holds, time will tell. It says 'gasket maker' so that means it holds up to cylinder-level heat, should be find for the crossover tube level of heat.


Thanks everyone for the help on this one.

any 100% silicone you buy at lumber yard is high temp,cheaper to buy a caulking gun tube of it

-

yep :laugh:

PLUMMEN wrote:

newOld_kz1000 wrote:

Patton wrote:

High temp silicon -- thanks Patton, I will have to pick some up -- I just hope my copper re-pipe holds, time will tell. It says 'gasket maker' so that means it holds up to cylinder-level heat, should be find for the crossover tube level of heat.


Thanks everyone for the help on this one.

any 100% silicone you buy at lumber yard is high temp,cheaper to buy a caulking gun tube of it

In other words its the same stuff just different packaging.

By the way, any chance you can enlarge that photo, especially the one with the leopard bikini. :silly:

martin_csr wrote:

newOld_kz1000 wrote:

....
However I am pretty sure I have a clog(s) in my low-speed jets in one or 2 carbs, she drops a cylinder, sometimes two, at idle. I will get to that directly....

Just a possibility... If you haven't done so, redo all of the spark plug wire connections from the coils to the plugs. The spark plug wires unscrew from the coils. The connections become poor from oxidation over time. Some dielectric grease wouldn't hurt.

I solved an intermittent firing problem on #1 & #2 by doing so.
It's easy & doesn't cost a cent - wouldn't hurt either.

If there's a lot of the white crusty stuff, you may need to nip off the wires a tad, but not too much so that the wires don't end up too short.

I will try that first. Maybe get lucky, the oxidation wouldn't surprise me, this kz650 has been outside for a while in its history.