Cat Delete...........

[DeeJay]

Pictures of my de-cat modification.
I used a small angle grinder with thin cutting wheel to open the can.
Some time ago I knocked a hole in the baffle plate at the original exhaust, and I would’nt like the bike to be too noisy - so I drilled a number of holes at two stainless steel pipes and welded the two pipes together with a stainless steel washer in between.




There seem to be a definite engine power gain. Not much, but I definitely noticed a difference. I also like the sound - the bike is not too noisy, but now has a nice extra little “grunt”.

 

[Moto-Kafe]

Following up on a thread I started a few weeks ago.........
I didn't mean to start a "debate" on pollution, do's and don'ts, pro's and con's, etc of messing with the Catalytic Converter. I just wanted to document what I did in case someone else was interested.
OK, the Cat has been "neutered", the system sewn (welded) back up, re-installed, and ridden "briskly" today in some beautiful Alabama Fall Weather. Everyone wants to know: did it make a difference?? The answer is yes and no.......and/or "maybe"?? Unfortunately, I also changed out the rear sprocket to a 45T unit while the exhaust was being cannibalized.........so, with today's ride, I can say 100% that it pulls harder and is much easier to ride (my style of riding). Is all this due to the gearing change, maybe. I don't have a baseline MPG reading on this bike (2012, bought back in October, 10k miles), so I cannot compare those numbers either. The bike DID loose 2 lbs in the process (the converter core), and might be a red hair tad louder (think Bass, not Treble) than OEM........or, it could all be in my feeble little brain. Anyway, I'll post the pictures below.....some may be "disturbing" to young children and NC700X Purists, so discretion is advised when viewing. The process involved taking an electric handsaw and Dremel Disc to the converter "cone".......opening up one side of it. I soon discovered the catalyst cylinder inside is actually spot-welded to the cone by the (4) welds you see on the outside. These (4) weld "blobs" had to be cut-out as well......not a pretty site. The catalyst cylinder inside weighs 2 lbs and is the Honeycomb type. Once the cancer was removed the side was sewn back up and the spot-weld holes filled back in (I actually cut up part of the catalyst cylinder and used some pieces since it's OD matched the ID of the cone (for making some "plugs" for the spot-weld holes). While I had the exhaust off, I "ported" (i.e. smoothed) the inner ring (ring = I think it was a weld all the way around on the inside of the exhaust flange) at the flange mating point with the cylinder........"opening it up", so to speak. (see pics). Bolted the system back up and went for a nice ride..........

Pics..........(I'll use 2-3 "Posts" for the pics....not sure if there is a pic size limit??)

(well, the pics are out of order....start at the bottom and go up.....duh!!)

 

[Moto-Kafe]

next set of pics.....

continued..........(again, start at the bootom and work your way up on the pics)

 

[Moto-Kafe]

Finished product..........




Of course, all these mods are for "Racing Purposes Only".......your results may vary.

 

[mtiberio]

given that 16 (yes sixteen) supertankers (or maybe container ships, I forget) produce more pollution than ALL the cars on the planet, I don't think your cat removal is that bad...

 

[anglachel]

So what was your MPG when all was said and done?

As for pollution and motorcycles.... EPA testing is available online.
Annual Certification Data for Vehicles and Engines | Compliance and Fuel Economy Data for Vehicles and Engines | US EPA

Though I have to admit I'm not exactly certain how to read the results, and the NC is listed in g/km instead of g/mile used on the car side... a comparison should be able to be made...

NC is in there (For at least the 2012 model year) and my car is in there... and if anyone can figure out how to read the data the rest should be easy to compare...

 

[jayceegee]

Am I correct in understanding that the only accomplishment to this quest for knowledge was a loss of 2 pounds ?

 

[rippin209]

It would have been great to get pre and post dino numbers. If there was a gain I'm sure it was minimal but I'm curious if there was a loss? My concern would be that currently it's mostly a power curve, I wonder if he got a flat spot or even a dip?
When I put a slip on my NC it felt like climbing the mountain range I go over on my commute I'd developed a flat spot. I don't have anything to prove this(no dino numbers), it was just a feeling but I tried it for a couple weeks and went back to the stock. It was a small difference but it defiantly wasn't a improvement and I already wish the NC had more power.