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Cutting out cats

glazier

Junior Member
When I remove the cats from my bike, do I need to do anything to the fuel mixture or will the computer adjust it as needed? The tech at the dealer said I need a download or a tuner, but other people say you don't. I don't have a tuner yet, but will get one soon, but want to remove the cats asap. Also saw where some people are drilling the cats out with a 14" long coring bit. Then you don't have to cut and weld the headers. Any one know anything about this? Am I better off to cut them out or does drilling work just as well?
Thanks
 
To do it properly you should take a cut off wheel and cut a rectangle out of the pipe,then remove the material inside.I use a small air chisel.Then weld the section you have removed back in.Coring with a bit only remove a portion of the cat and if you experience decel pop the loose pieces could be sucked back up into the valves.Laugh,but it has happened.
On your second question these bikes are already too lean in stock form.Add a fueler.
 
I decided to purchase a header pipe with the "cat" already removed, it was cut and re-welded. Based upon the way the header pipe is made, I have difficultly understanding how all the "cat" material can be removed otherwise.

IMO the stock bike is running too lean, removing the "cat", even if the ECU adjusts for that change, it is still too lean.

I contacted Fuel Moto, purchased a tuner loaded with a program to handle the "cat" removal and air cleaner change. To date, considering the weather has not allowed lengthy riding, it seems fine, really has opened the bike up.

Some tuners allow multiple programs to be loaded, you could order one for the "cat" removal now, with a second program in it for future mods, such as a air cleaner.
 
I agree that the bike runs too lean from the factory but I think the question is will it be ok to do the mods in stages? My answer is still yes. Putting a less restrictive exhaust on first with the air still being restricted with the stock air cleaner is fine if your budget can't afford the fuel tuner now.

Agree, you can change the air or the exhaust, but not both with out adding more fuel, tho more fuel is already a big plus as the EPA has been leaning out these engines since the EVO days
 
To do it properly you should take a cut off wheel and cut a rectangle out of the pipe,then remove the material inside.I use a small air chisel.Then weld the section you have removed back in.Coring with a bit only remove a portion of the cat and if you experience decel pop the loose pieces could be sucked back up into the valves.Laugh,but it has happened.
On your second question these bikes are already too lean in stock form.Add a fueler.

Oh I wouldn't laugh at that. I had already thought about that happening. Thats why I didn't think it was such a good idea, but have read that people have done it and didn't even remove the pipes. I don't need any junk getting sucked into the valves. And when I cut out the rectangle, how far towards the front of the pipe do I need to go? Maybe the entire flat piece of metal? I'll cut it out and remove the cats, but will have to take it some place to have it welded. Got these pipes on Ebay and they were supposed to be off an '09 with no cats, but the seller didn't know for sure. (now he tells me). But at least the O2 sensors are in the same location and I'll save my stock pipes just in case I need them in the future.
 
you can drill your cat out with a 1 inch x 16 inch paddle bit. you need to take pipe off of bike and remove o2 sensors, mount pipe in vise and run the bit in and out of pipe until all of cat material is gone. take your time and you will get every last little bit out of pipe. done this to 4 bikes and works well and you can do it for $10. don't breath the dust from drilling not good for you.:USA
 
you can drill your cat out with a 1 inch x 16 inch paddle bit. you need to take pipe off of bike and remove o2 sensors, mount pipe in vise and run the bit in and out of pipe until all of cat material is gone. take your time and you will get every last little bit out of pipe. done this to 4 bikes and works well and you can do it for $10. don't breath the dust from drilling not good for you.:USA

A wood type paddle bit? That would cut the cats? Where do you find a 16" paddle bit?
 
In post #7 you said at least the o2 sensors are in the same place.I assume you mean the ones you got on e-bay versus your 2013?'09 headers don't have the cat but the o2 sensor is near the head,2010 and later are near the tranny side cover below passenger peg.2010 and later have the cat. Larger bung for o2 sensor on '09 also.
tourbox
 
In post #7 you said at least the o2 sensors are in the same place.I assume you mean the ones you got on e-bay versus your 2013?'09 headers don't have the cat but the o2 sensor is near the head,2010 and later are near the tranny side cover below passenger peg.2010 and later have the cat. Larger bung for o2 sensor on '09 also.
tourbox

read post #7 again :D
 
I re-read the post #7 but still confused.You got a set off e-bay and those are the ones you want to de-cat,correct. On those pipes where are the o2 senor bungs located?
tourbox
 
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