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Online bansheebeat

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Removing the cat box - bad idea?
on: September 29, 2020, 05:05:56 AM
There are a few local shops that can remove the cat box from the stock headers and fit a new mid pipe. Has anyone done this? What was your experience? Results? Regrets? Anything to look out for?

Offline Evangelos K

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Re: Removing the cat box - bad idea?
Reply #1 on: September 29, 2020, 06:11:51 AM
I would have it no other way.  When you hold that assembly in your hands, you will realize how HEAVY 12LBS feel and are when concentrated in a small area.  Heavier than the heaviest motorcycle battery.  Save about 11LBS, since the new midpipe would be about 1.5LBs, install a lithium battery, and marvel at the tangible feel of weight savings.  And also the looks, SO MUCH better.

It is louder obviously than stock, but nothing extreme.  And no adverse effect on performance (or gains really, without a flash - maybe a slight top end gain as is).
2018 Triumph Tiger 800 XRx
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Online bansheebeat

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Re: Removing the cat box - bad idea?
Reply #2 on: September 29, 2020, 07:06:45 AM
*Originally Posted by Evangelos K [+]
I would have it no other way.  When you hold that assembly in your hands, you will realize how HEAVY 12LBS feel and are when concentrated in a small area.  Heavier than the heaviest motorcycle battery.  Save about 11LBS, since the new midpipe would be about 1.5LBs, install a lithium battery, and marvel at the tangible feel of weight savings.  And also the looks, SO MUCH better.

It is louder obviously than stock, but nothing extreme.  And no adverse effect on performance (or gains really, without a flash - maybe a slight top end gain as is).

I'm mostly wondering on the difference between just buying aftermarket pipes vs de catting the OEM pipes. Decatting is much, much cheaper. But obviously there's "no going back" once you do it.

Offline Notsoaverageguy

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Re: Removing the cat box - bad idea?
Reply #3 on: September 29, 2020, 05:20:24 PM
I de-catted my pipe and removed entire baffle assembly also cut 8" out of the width. Reason is I still like jacking the bike up by the bottom bread box supported. So maybe not quite as light as just a pipe, (also made a muffler out of the narrower mid pipe) but also have a Lithium battery . See (battery/trunk/weight loss)  And I was surprised that I can actually feel the difference in weight while riding. Didnt expect that.
Things should be made as simple as possible, but no simpler!
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Offline kernowjim

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Re: Removing the cat box - bad idea?
Reply #4 on: September 29, 2020, 08:22:43 PM
I would say cutting the original exhaust is a bad idea, due to the cost of replacing it and when you come to re-sell the bike or trade it - most dealers want a stock bike.  I doubt whether the bike would run correctly without the back pressure it provides and would certainly need reflashing or dyno work - it all gets expensive in the end.  If you just want noise, go right ahead.

Offline Notsoaverageguy

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Re: Removing the cat box - bad idea?
Reply #5 on: September 29, 2020, 09:29:09 PM
Well a little clarification. Mine runs perfectly after the mod. (no baffles or cat) and I have now purchased 2 stock headers from 2 different members here for 300$ each. So maybe not so bad.
Things should be made as simple as possible, but no simpler!
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Offline Seventies four e

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Re: Removing the cat box - bad idea?
Reply #6 on: September 29, 2020, 09:50:05 PM
In order to check ergonomics of this bike I borrowed a friend's standard bike and rode it for a couple of hours and nearly 100 miles, well loved it and within a week a z900rs was sat in my garage mine was de-catted....... Would I swop it for standard, hell no I believe everything is better with de-cat I'm sure this I the bike Kawasaki would have made if the tree huggers and euro meddlers would allow.

Offline kernowjim

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Re: Removing the cat box - bad idea?
Reply #7 on: September 29, 2020, 11:41:00 PM
*Originally Posted by Notsoaverageguy [+]
Well a little clarification. Mine runs perfectly after the mod. (no baffles or cat) and I have now purchased 2 stock headers from 2 different members here for 300$ each. So maybe not so bad.

Well I'd like to see a dynograph of before and after - if it does run properly without a flash then great. 

Offline Notsoaverageguy

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Re: Removing the cat box - bad idea?
Reply #8 on: September 30, 2020, 12:05:56 AM
*Originally Posted by kernowjim [+]
Well I'd like to see a dynograph of before and after - if it does run properly without a flash then great.

Well I am certainly not going to pay 300$ for a Dyno graph nor do I care to prove what I already know. So here is a pic of the exhaust color after several thousand miles. It doesn’t get to look any better than this.


Things should be made as simple as possible, but no simpler!
(Albert Einstein)

Offline Dirty Dave

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Re: Removing the cat box - bad idea?
Reply #9 on: September 30, 2020, 02:01:52 AM
Mine looks slightly golden in colour compared to yours NSAG at the muffler end.
Slight bit of carbon inside.

Akra header, stock muffler with flashed ECU so O2 sensor off.

I'm running richer then......
18 Z900RS Jaffa
97 Honda Valkyrie
79 Honda GoldWing