[Senecagreen]

I ordered a mid pipe. rather than cut the cat and hollow it out and attach it there I would like to cut right behind cat and shorten mid pipe to attach there instead using the stock hanger that comes on the mid pipe.

These bikes have high flow cats and make 145hp stock. This would be a cat back using stock muffler. If it won't run right will send my ecu to moore mafia and tell them my mod. Stock air filter
2016 gsxs1000.

Has anyone installed a mid pipe and kept cat and exhaust valve? What were your results?

 

[aztrex08]

Wondering if this is possible as well. I would like to keep the cat and muffler. Removing the servo and bread box. I would use the ESE servo eliminator. Wondering if this is possible... Shorter link pipe? or modify the link pipe? Sound level change?

 

[FreePenguiny]

I did, my 2018 gsxs I used link pipe but left flapper and cat but then eventually drilled the cat out
But left flapper entirely

 

[Senecagreen]

The 02 sensor is first after headers, then flapper, then cat, then box. I am hoping to cut box where it is welded to the cat preserving the complete cat, then modify mid pipe for that configuration so that the stock muffler locates in the stock position.

Once I am done I will cut the top off the box so we can all see what is in there.

The thought is by making a cat back exhaust the stock tune won't be messed up. We will see....plus with the cat still there it won't be super loud as the cat suppresses quite a bit of noise.

 

[Senecagreen]

Most directions say make the cut on the exhaust 95mm back for the mid pipe install. Will have to measure the remaining length of cat to box from there as there is 40mm of room on the mid pipe where it can be shortened. The mid pipe can be marked so that the geometry doesnt change.

If I can't successfully shorten the mid pipe and keep the cat I probably won't do it.

 

[aztrex08]

Please keep us informed on your progress

 

[Senecagreen]

Shortening the mid pipe seems to be the way to go. Marking a line on opposite sides of the mid pipe in the area Im going to shorten will make sure I can fit it up on the bike and the orientation of the hanger and the outlet is right.

I have a tailpipe expander to make sure the upstream part of the pipe slides into the downstream part and will install it all with the muffler to make sure everything lines up correctly before marking the mid pipe again, then removing it and having it welded.

Time consuming but I have another bike to ride and it's not quite riding season here yet.

 

[Senecagreen]

Getting started

 

[temporarykiwi]

increasing the tailpipe size will aid power, it is quite small stock

 

[Senecagreen]

Im just trying to keep the first cat whole to keep the db down and get rid of the box otherwise a Arrow or M4 header would be considered.

 

[871JZ]

Im just trying to keep the first cat whole to keep the db down and get rid of the box otherwise a Arrow or M4 header would be considered.

There's two catalytic converters on our bikes. The first one is just behind the exhaust valve and the second one is inside the turkey tray. If you cut 1/2" further back from the specified location, you will still retain the first catalytic converter.

Initially, I installed the same cat delete pipe you have and I cut 1/2" further back from where the instructions specified. It ended up being just behind the first cat, which was perfect. I left that cat in place, along with the exhaust valve. There's no need to modify the cat delete pipe in order to keep the first cat in place.

 

[aztrex08]

There's two catalytic converters on our bikes. The first one is just behind the exhaust valve and the second one is inside the turkey tray. If you cut 1/2" further back from the specified location, you will still retain the first catalytic converter.

Initially, I installed the same cat delete pipe you have and I cut 1/2" further back from where the instructions specified. It ended up being just behind the first cat, which was perfect. I left that cat in place, along with the exhaust valve. There's no need to modify the cat delete pipe in order to keep the first cat in place.

Without changing the mid pipe, did the mounting bracket bolt hole line up? How loud is it using OEM muffler?

 

[871JZ]

Without changing the mid pipe, did the mounting bracket bolt hole line up? How loud is it using OEM muffler?

I'm not sure what you mean regarding not changing the mid-pipe. I removed the complete factory exhaust system, cut it behind the first converter (which got rid of the turkey tray), and then installed the cat delete pipe. In the end, it was a completely stock exhaust system with a cat delete pipe installed. All the mounting holes on the cat delete pipe lined up perfectly and it was quite a bit louder without the turkey tray and second converter in place, but it still wasn't as loud as the full system I'm currently running. The way it sounded was alright, but not as nice as the full system.

ETA: This was on a 2020, not a new generation bike.