# Outty "exhaust mod" - build w/ pics



## JPs300

Wanted to do something with the exhaust on the bike, but after having had several fairly loud bikes I wanted something a little quieter, but with a nice mellow tone that still lets you know it's an angry 800 at heart. - Having been around my buddy's HMF swamp I was thinking of going that route but figured I'd give the "stock exhaust mod" a shot first, as I've been bleeding money on this since only getting the bike a couple weeks back. 

First step - cut stock muffler end cap loose, I used a 4" cut-off wheel on an angle grinder: 









Using a punch and hammer and moving around the edge I was able to drive the stock spark arrestor out: 


















**Now, at this point I'd recommend re-installing the muffler and deciding what you thing of the sound. I have read on various forums where people took a drill and drilled the next baffle wall(can be seen in above pic) with everything from two 3/8" holes up to multiple 1" holes; since I didn't want mine overly loud, I left the rest of the muffler as is. - IMO, just removing the rear cap & spark arrestor gave me slightly quieter tone than the regular swamp series but also a slightly lower/deeper tone. VERY happy with it, though it would be a little louder like this than I sometimes want; will address that in later pics. 

For my next step, I cut a piece of 14g steel out to fit as a new end cap for the muffler. I had decided to run a short exhaust snorkel up to the bottom of the racks, and had chosen to use a 2-1/2" mandrel mend to do so. The large diameter will help maintain a deeper tone. - After hearing the exh just with the stock arrestor removed I decided to make the snorkel/tip bolt-on, that way I could build a drop-in "quiet core". To do so, I simply welded five 1/4" nuts on the inside of my new end cap & then welded it to the muffler case. 









I then built my "quiet core", using a short section of 2-1/4" exhaust pipe. I mashed the end shut in a vise, similar to how the stock spark arrestor end is closed off. I then cut four rows of 1/2" wide slits equally spaced around the outside, using a 1/4" offset between the rows. After doing so, I set the pipe in a section of angle iron & using a punch & hammer I dimpled the leading edge of the pipe down at the slits.I then welded an 18g steel "ring" around the end to sandwich it in place between the muffler end-cap and the tip. 

End result looked like this - 









Pics from another muffler job I did to help illustrate how to build the baffle - 
Slits: 









Partially punched downward: 









Looking inside after completed: 









I then cut a second end-cap plate & welded my snorkel/tip on. As eluded to above, I used a 2-1/4 mandrel "J" bend; cut in the center to leave me two 90* bends, then cut to desired fitment & welded together. 

All finished & bolted up: 




























The Power gain is definitely as noticeable as any slip-on aftermarket performance pipe. The sound is absolutely perfect for what I wanted and with the removable core I have the option to be more obnoxious whenever I feel like it! 

- Not bad for a couple evenings after work & $40-50 in materials.


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## Polaris425

awesome!


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## Crawfishie!!

DAYUM, that's awesome. 

Mud slingin' and COLD beer drinkin'


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## JPs300

Will try to remember my video camera this weekend to get some riding vids & some sound from this thing. - Tried to get a clip with my phone, but the audio quality sucks.


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## filthyredneck

Looks like this will be my next mod. Have you noticed if your bike is leaning out any? The gade is a hair warm since I added the 2"intake snork. 
....PC-V is next thing on my list to buy, but its gonna have to wait another month or so because my injector pump is going out on my dodge...new VP44 SO is gonna hit me for $950 

"Killing Time Using Tapatalk 2"


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## TINGS

Looks great!
I think i may have to give her a try


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## JPs300

I'd bet the engine is a tad leaner by how it feels/acts, but my exhaust heat is actually lower(likely due to less back pressure). - I think down low the a/f is pretty reasonable, up top it could probably use some added in. It's not far enough off to make the PC5 a priority for me yet.


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## filthyredneck

I didnt think about the flow being less restricted, good chance thats l thatd help me in the same way 

"Killing Time Using Tapatalk 2"


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## JPs300

jrpro has already done the mod to his 1k renny, I believe he gutted his almost completely and I don't think he has a programmer on his yet either.


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## fstang24

thats a pretty cool mod


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