Removing Cat Converter?

[FZ1inTX]

Removing the CAT isn't making the bike more noisy... I'd call it a deeper and richer tone. I suppose it is more noisy but it is in the very low frequencies.

You could get the full Yosh and sell the slip-on separate, just keep the header, right? :tup:

 

[NJFZ1]

I had a look on the holeshot website at the 4>2>1 headers, it looks very nicely fabricated and will work with most slip-ons, but it is $ and on ebay I see a full yoshi system for not much more?. So please correct me, in order to keep back pressure leave the cat in. It got me thinking has anyone removed 1/2 of the cat or has replaced the cat wih something that allows more flow but still has the required back pressure?. I suppose if your gains are minimal only noise it is pointless mod. I have the Mivv titanium slip-on is it awesome fully recommend it.

Well technically you already removed "half" the cat when you replaced the muffler. I know you were referring to the cat in the header and that is a single unit. Once you remove a piece of it it's integrity will be compromised and it will eventually start losing other chunks, which will invariably become lodged in your muffler. In other words don't mess with it unless you're going to completely remove it.

My personal advice is that since you already invested in the MIVV leave the header alone. For those that are contemplating replacing the full exhaust the Yosh R-77 or TRC can't be beat. Might not look the prettiest, but it gives you proven power...

 

[Buildercher]

No disrespect to Ivan, i have his products on my bike and they a brilliant, but has he done a dyno test to prove this fact? and if so has he posted it?. From reading through the threads I have noticed the some vital information missing. You lose back-pressure that aids engine braking, anyone who rides on the track or fast road will know the importance of engine braking!!!. It has been mentioned twice in all the treads from what I see, I wonder how many have butchered the cat and have found this out?. Thanks for the advice I will stick with my slip-on as I cant justify spending $ on headers or a full system for minimal gains and the expense of having to dyno again.

 

[old rice]

I had a look on the holeshot website at the 4>2>1 headers, it looks very nicely fabricated and will work with most slip-ons, but it is $ and on ebay I see a full yoshi system for not much more?. So please correct me, in order to keep back pressure leave the cat in. It got me thinking has anyone removed 1/2 of the cat or has replaced the cat wih something that allows more flow but still has the required back pressure?. I suppose if your gains are minimal only noise it is pointless mod. I have the Mivv titanium slip-on is it awesome fully recommend it.

With the stock can and the 2 cats removed you will still retain the exhaust throttling valve. This will trim the back pressure for what ever rpm range your running in. I just bought a spare stock can for cheap for experimental purpose. It already has the cat removed so All I will need to do is remove the cat in the header pipe. I hope to get clean increases in all rpm ranges and reduce some of the engine heat. I should get a bit more growl out of it. Completely stealth. Correct me if I am wrong.

I also may gut the can and shorten it by several inches on the back half beyond the hanger and run a straight pipe inside the can, pack it and weld it back up, and repaint. Perhaps provision for a removeable lolypop incase I want to play with the sound. Suttle but kick ass I think. Then Just a air box mod. Anything beyond this = poor $$ to performance ratio. As long as that exhaust valve is working the FI should be able to handle this. Can is on the way will post progress.

 

[Rusty]

After speaking to my dyno guy earlier in the week and him recommending it, I've gutted the cat this morning.
The PCV is going on tomorrow when the bike gets its first 600 mile service then it's off to the dyno once the smog plates arriv and are fitted:yes:

I've not had a chance to ride the bike yet with the cat out so can't really comment on any differences yet!