This is how I removed my muffler box.
(1) 3"-to-2.25" stainless exhaust reducer 3" long $21 amazon (Stainless Headers Mfg SHM-2.25T-3SS)
(2) stainless flanges for 2.25" (57mm) pipe 1/2" thick $38 siliconeintakes.com (EXH009536)
(1) 2.25" stainless elbow 45 degree 2" long $25 amazon (TS Performance cxracing 10611001910)
(1) 2.25" stainless tubing at least 1' long ?
(1) stainless 304 flat bar 5.25" X 1.5" X 1/8" thick $21 speedymetals.com
(1) 2.25" chrome angle cut exhaust tip heavy guage (9") $22 ebay (seller: shellyjarrett)
(1) Servo Buddy for a 2005 GSX-R1000 $57 ebay (seller: wickedracingstore)
Remove header assembly (Be sure to use cloth protection as the manual states, or you will scratch the tank like I did)
Cut off the large muffler box with a chop saw
Cut off the right mounting ear from the muffler box
Cut a 1 5/8" spacer (from the stainless tubing)
Weld the reducer, spacer, and flange #1
onto the header (The spacer should protrude through flange #1
and half way into flange #2
Make the bracket by welding the ear onto the 5.25" flat bar
Bolt the bracket on
Bolt the header on
Weld the bracket onto the reducer and spacer, just in front of flange #1
Cut a 6" spacer for the exhaust tip (from the stainless tubing)
Expand the spacer's diameter so it fits nicely inside the tip (the tip is larger in diameter than the spacer)
Weld the spacer to the tip, leaving 1" of the spacer sticking out of the tip
Mark location of weld of flange #2
, 45 degree bend, and tip (make sure you mark them correctly)
Weld them together (be careful not to let the elbow protrude more than half way inside the flange) (dont weld the elbow on backwards!)
Bolt the 2 flanges together
What I should have done:
The first spacer should have been 3 5/8" long, so the bracket could be vertical. This would put less stress on the bracket welds. It would have put the tip closer to the rear tire, but there is enough clearance.
After reading comments on the web about the exhaust valve, I think it is there only to reduce noise. I do not think it is neccessary.
If you turn the key on after the exhaust valve cables are disconnected, one of the cables retracts. This makes it impossible to connect the cables back without disassembling the servo motor to extend the cable (which is very difficult).
BTW, if the cables are disconnected, and the spring is removed, the exhaust force will keep the valve closed! The spring will keep it open if its left on and the cables are disconnected.
I did not connect the cables back up to the exhaust valve. Therefore the dash displayed an FI error.
To eliminate the error, I bought an exhaust valve FI error eliminator (Servo Buddy) from ebay for $57.00 (Also fits a 2005 GSX-R1000)
I sold my 2004 GSX-R1000 just before I did this mod. I had previously removed the muffler and put a straight pipe on it. But I kept the exhaust valve hooked up. It did not have a CAT. Therefore the only thing in the exhaust path on my 2004 was the valve. It was very loud at full throttle. How did the sound of my 2004 compare to this S1000? Well, the S1000 is not quite as loud, but it has a much deeper tone. Honestly, I liked the sound of the 2004 better. Not because it was a tad bit louder, but because I think it had a better tone. I am glad I didnt remove the CAT on this bike, because it would not have made it very much louder. Plus, I didnt want to change the mapping.
Snatching throttle on rough roads:
It was really bad before this mod, and it is still really bad. I plan on trying to improve it later.
I hit a top speed of 155 MPH (as indicated on the dash) before this mod. I also did it after this mod. Of course this mod did not affect the top speed. The gearing prevents it from going faster. It has plenty of power to go faster. I plan on changing the gearing to go faster, and I will post my results later.