Exhaust Rusted Tight

[Nessman]

They all do that...I know.

So I've got this '78 Standard with a pretty decent (considering the rest of the bike) exhaust that I'd like to use again but every joint is stuck. If I could get it off the bike I could get some room to "work" the joints but she won't clear. I *could* try to remove the head exhaust studs but that's another can of worms I'd rather not open.

It can't move forward past the studs because the crossover hits the centerstand. It can't move down because it tucks above the frame and won't splay enough to clear and the head studs foul the path.

I really don't want to cut it up but that may be how the story ends. I have a set of cheap Dunstall knock-offs I could use but the originals match the patina.

 

[angus67]

I would just cut the crossover. if you put it back on, no one will know.

 

[Nessman]

I would just cut the crossover. if you put it back on, no one will know.

I had my angle grinder in my hand today but thought better of it. Next step (if there's no magic bullet from the forum) is to cut the crossover and weld a sleeve over the cut so it looks normal unless you pay attention.

Thanks Angus.

 

[DogBunny]

You need to loosen the crossover. Remove all of the other hangers and bolts as far as you can, then go at the crossover with a big hammer and piece of 2 x 4 long enough to reach under the bike to the far pipe while you crouch by the bike. Place the 2 x 4 right where the crossover is welded to the opposite side muffler, and hit the other end of the 2 x 4 hard. Then go to the other side of the bike, and do the same thing. Work back and forth. Of course, use penetrating fluid at the crossover joint. This WILL work. The crossover joint will separate.

 

[fredintoon]

Hi Nessman,
it's real awkward trying to swing a hammer under there.
try jacking it off.
Length of 3/8" or 1/2" threaded rod, a length of tube that fits over it, some plain washers and a 3/8" or 1/2" nut makes a jack that fits between the two mufflers.
You'll need a vise-grip to hold the threaded rod and a ratcheting box-end wrench to work the nut.
Loosen every fastener holding the exhaust together and on the bike.
Slather everything with a good penetrating oil and leave it soak overnight.
Put the poorboy jack in there and ratchet away to force the crosstube joint apart.

 

[650Skull]

The weakest points will be where the crossover is attached to the mufflers. Any smashing or force against the mufflers is directed to these points. If the crossover separates from them there then kiss them goodby.

I would go the angus67 route. Quick, easy fixed and back on the bike.

 

[glennpm]

You mention the crossover hitting the center stand. Can you unbolt the center stand to get enough clearance?

If you get the whole assembly off, use PB blaster and let it soak in to do its magic.

When you reassemble put anti-seize on all the slip joints and you won't have the same problem the next time.

 

[gggGary]

No matter how tight they WILL come apart unless rust has weakened the system in other places. Patience is key. loosen or remove all bolts, clamps. Yes keep hitting all joints with your favorite rust blaster. If you are trying to save, reuse the exhaust cut shape wood beating blocks to fit the pipe OD, hardwood is best. Two people is very helpful, one to pull, twist, work back and forth while the other uses wood blocks and a largish hammer to rattle the joints. Stop and go backwards ie back together now and then, this actually will make the full removal easier. You can get the whole system off the bike. I think, as someone mentioned, removing center and maybe even side stands makes it "easier", HAH HAH!

The cross over joint has an "asbestos" sleeve inside so it will loosen, flex and eventually release.

 

[Nessman]

I WON!!!

Mr. Goldberg to the rescue.

The final solution, after a can of PB Blaster and a bunch of propane was wedging a couple of boards between the frame and pipes with a strap to tension. Lots of heat and some rapid vibrations with an air hammer tipped with an aluminum die *similar to what they use in the aircraft industry*.

With the first rattle on the clamp I saw movement a couple of buzzes and she was loose.

WOOT!! Now I can change the tire and ride the old girl.

 

[angus67]

cool. I haz same air hammer. Wheres the spring?
Its kind of a caveman hammer, but it does the job. I used one to punch holes in the collapsed exhaust on my xl250.
Any damage done?

 

[Nessman]

The pipe by the crossover clamp is kinda mushroomed from prying on it but otherwise we're good. Some hammer work should straighten things out.

Oh yea...now I get to order some brass swingarm bushings.