How To: Shorten stock 06+ R6 Exhaust / Slip on / Muffler

This isn't very difficult to do as long as you have the tools, this was the first exhaust i had cut down so i thought I'd make this guide to help out other first timers.
Please note that i trimmed 110mm off of mine, and that you cannot exceed 130mm otherwise your end cap will interfere with the mounting bracket.

This - to this -

Items you will need:

• Drill
• Drill bits (5mm)
• Hacksaw / Grinder
• Scribe / Pencil / Felt pen
• File (preferably a round one)
• 5 4mm-5mm Stainless steel rivets
• Tape measure
• Rivet gun
• Masking tape

Items that are recommended but not necessary:

• MIG welder
• Rivet drill bits (5mm)
• Medium sized Phillips screwdriver
• Gloves (for handing exhaust packing)
• Aluminum tape / can
• High temperature adhesive

Before we get started I'll label the picture so you understand what part(s) I'm talking about in the following steps to avoid confusion:

1. Exhaust Housing
2. Baffle
3. End Cap
4. Packing

Step #1.
Begin by drilling out the rivets around the end piece of your exhaust (there should be 5 in total). Once the rivets are removed the end cap should easily slide off.
TIP(s):

1. If you are like me and are talented at snapping drill bits invest in some rivet drill bits, they are double ended and short so they won't snap easily!
2. Use the low speed settings on your drill, you will be less likely to snap drill bits.
3. Put your exhaust on an old towel so you don't scratch it.

Step #2.
Now you need to remove the baffle and packing.
It's jammed in pretty tight so i fed some rope through the hole in the exhaust tip, got a mate to hold the exhaust while i pulled the rope. Be carefully when doing this as it will come out pretty fast, and fiberglass packing falls everywhere.
TIP(s):

1. If you are having trouble getting the baffle out you can pry the end of the exhaust housing away from baffle frame by using a flat bladed screwdriver in the rivet holes you drilled. (It doesn't matter if you bend the end of the exhaust as you will be cutting some off from this end anyway)

Step #3.
Now mark 110mm from the end of your exhaust housing and cut it off using your Hacksaw / Grinder, once cut use your to remove the burr from the newly cut edges.
TIP(s):

1. You need to keep your cut as straight as possible or your end cap will not sit correctly and you will struggle to get all your rivets back in. So use your Scribe / Pencil / Felt Pen to mark your line ALL the way around the exhaust.

Step #4. (OPTIONAL)
Now is a good time to remove your EX-UP Butterfly Valve, only do this if you understand what it does etc. I removed mine because it is no longer used since I've removed the EX-UP Motor & Cables.
The screws in the valve are in fairly tight due to a very small tack weld on them, i couldn't get it with a screwdriver so i had to use my impact driver.


Step #5.
Now you need to cut the baffle to fit your re-sized exhaust housing.
If you have a welder handy, do the following:
Cut the small flange off of the end of your baffle and set it aside as you will weld it back on later. Now measure up 110mm from where you just cut the flange off and cut that piece out (you can throw this piece away).
Now you will need to weld the flange back onto your shortened baffle. Ensure you use a mig or similar welder, i began using a stick welder but it blew holes in the baffle because it was too thin.




If you don't have a welder, do the following:
Measure up 80mm from the end of your baffle and cut it off. The reason you cut off less on the baffle is so it will slide into the main exhaust pipe to prevent back pressure loss since you don't have the flange on the end.

Step #6. (OPTIONAL)
I heard of people using metal tape to tape up a bit of the baffle to loud-en the exhaust note, so i decided to do it. I taped up about 1 & 1/4 inches of the baffle. I couldn't find any aluminum tape in any of the auto stores where i am, so i just sliced up a can of coke.
If you managed to get aluminum tape, tape up enough of the baffle as you see fit, i recommend not doing more than half.
If you cut up a coke can, cut the top and bottom off the can. Then make 1 cut of the cylinder from top to bottom giving you a flat rectangular piece of aluminum. Now cut that to the width you want to cover on your baffle.
Evenly spread your high temperature adhesive (i used a silicon based RTV) on one side of the piece of aluminum and rap it around the bottom part of your baffle. Then put tape around that to hold it. Let it sit for a minimum of 24 hours before removing the tape.


Step #7.
Time to drill some holes in the exhaust housing so you can rivet your exhaust back together.
Slide the end cap on leaving the baffle out and mark your holes, then drill out your holes using a drill bit that is the same size or slightly bigger than your rivets. (I used 4mm rivets and a 4.5mm drill bit)


Step #8.
It's time to start re-packing that fiberglass packing, first off put your gloves on before handling the packing.
Now because the exhaust shape isn't a perfect cylinder you'll first wrap the fiberglass around the baffle as much as you can so it's reasonably level with the large baffle end, then use masking tape to hold it in place. Make sure you wrap it tight.
Now stick that pad looking piece of packing into the exhaust housing then slide your baffle in about 3/4's and start stuffing as much fiberglass in as you can fit. Once you're content with the the packing situation push the baffle all the way in lining up the holes on the baffle with the holes on the exhaust housing.
At this point making sure there is no fiberglass packing obstructing the baffle. (Just look straight down the pipe, if you see no packing squashed in there it's all thumbs up)



Step #9.
Final step! Slide your end cap on, push the rivets in and use you rivet gun to secure the end cap on.
Make sure you squeeze the rivet gun slowly so you get the rivets in nice and tight.
Congrats, you've successfully shortened your exhaust!

 

I think I speak for all of us when I say...What ?!

 

Haha, don't worry dude i'm typing this up for another forum.
It's just gonna take me a few days so i thought i could do it here so i could just do bits at a time.

 

Should put this in the guide section, pretty detailed. Nice.

 

Ha, cheers bro.
But i doubt this would be relative to anyone on these forums.
I'm doing it for other forums, but I'm still currently in the middle of doing it. So i just keep updating it as i go, then i can just copy and paste onto that site.