BUILDING A STREET LEGAL KX500 SUPERMOTO

[Sandblaster]

I worked a bit today making a new muffler.
I took a FMF Power Core and shortened it 5.5"
In Oregon we can get a sound ticket for being too loud in the woods, sand dunes or any other state ran riding area.
On the street, you can run whatever.
Makes perfect sense to me
Here is what I started with:

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First step was disassembly.
Whoever owned this before replaced the packing and sealed both ends with silicone.
I would not recommend using silicone to seal your muffler ends if you ever plan on packing the muffler again as it was very difficult to get it apart.
Since I was cutting mine anyway it wasn't as big of a deal.

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With the muffler cut I removed both end and the packing material.

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With all the material removed I cut the inner perforated tube to the correct length.

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Then I drilled the new end cap holes.

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New packing material....

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Assembled it.

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It took about an hour to do this because I had to go next door to a machine shop and borrow a water cooled band saw to cut the muffler in half.....
Sometimes it adds to your build time because you need to say hi to everyone, answer all their questions ect...
Still I am very happy with how this turned out.
Next, I am thinking about beveling the bottom....
So stay tuned....

[Sandblaster]

OK, I couldn't leave well enough alone.
After marking out my cut lines I decided to start cutting

KX500 SM MUFFLER MOD1

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KX500 SM MUFFLER MOD2

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KX500 SM MUFFLER MOD3

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A few more tweaks and a trip to the weld shop and I'll have something a little different.
I also ordered some square tubing for the outlet....

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More to come...

[Sandblaster]

Here is the project after first stage welding.

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More to come after I get my square tubing...

[Sandblaster]

And then I started thinking about.....

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[Sandblaster]

Here's where I am at tonight.

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Now I'm waiting for the aluminum tubing to come in.

[Sandblaster]

Or, perhaps I'll do something like this:

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[Sandblaster]

I was asked how I was going to make the internal baffling.
This is a rough idea.
I am tying the two pieces of internal baffling with some small pieces of plate not shown in the pics.
The lower tube will be functional but the upper tube will take the major volume of exhaust.

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Even though this will be primarily for street use I am installing some stainless steel mesh for a spark arrestor.

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[Sandblaster]

The aluminum tubing arrived today so I cut it in half at the approximate finish angle and took the pieces to have them tig welded.

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Once the pieces are tigged together I will finish shaping them and then have them tigged to the muffler body.

[Steve O]

Now your just teasing us!

[Sandblaster]

Now your just teasing us!

That's not teasing, this is

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