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Exhaust system

  • Thread starter Deleted member 1183
  • Start date
D

Deleted member 1183

In the course of trawling the web for engine crashbars, I came across this little gem. I recently damaged my header pipe offroad and was facing a $600 bill to replace it if it could not be repared. However it was repaired. It is not comforting to know that I can get something much cheaper if necessary. See below.

Kit collettore elimina catalizzatore NC 700 X cod.8069 - 218.79EUR : Accessori Moto, Store

I have dealt with this store previously for Givi Trekers for my Triumph. Their prices are very reasonable and service excellent.
 
Couple guys on the UK forum have fitted these decat pipes and they both agree that the bike pulls better. One of these guys is Stuart who I ride with often. He was thinking of changing his bike as wanted a lil more go but after fitting a full Leo Vince system a few weeks back he is very happy with the performance increase. Any silencer can be used and it does not need to be a Leo Vince. Arrow also do a decat pipe which is in one piece I think and not several pieces like the Leo Vince. I will be getting a decat pipe myself at some point.
 
most bikes would run better without the catalyst converter .
the cat chokes the life out of most bikes and cars.
 
I wonder if a mapping adjustment is needed with the EFI when such a pipe is fitted ?
 
Maybe I'm looking at it all wrong, but I confess to being puzzled by that schematic of the exhaust pipe. It looks like it has a bolt plug for the O2 sensor, thus giving the impression it's also eliminated from the equation, and if it is getting rid of the cat, why is there a giant cat-shaped cannister in the header pipe downstream of the O2 bung?

LeoV pipe.JPG



For the record, Giannelli also makes a complete header and muffler system for the NCX. It looks "normal", with no weird stuff going on in the down pipe/s. Giannelli and Arrow pipes/mufflers are made in the same factory, by the way.

Based on the dyno chart (which I never really trust anyway, lol) the difference is really, really, really, negligible. That's saying something, if they, like all companies wanting to sell you stuff, are trying to do their best to slant the dyno numbers in their favour to begin with...

$(KGrHqRHJDIE-SFnrLFKBPsUWF14GQ~~60_58.jpg

min_3825_HONDA%20NC%20700X%202012.jpg

Having said that, the Giannelli full de-cat system and carbon muffler on my CBR made a huge difference with how the bike feels :cool:
 
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Interesting. The above dyno chart like the one on the Leo Vince site shows precious little change form stock yet they claim "Leovince DECAT CONVERSION removes the power sapping stock catalyst giving improved power and better pickup...", and I've seen a number of reports form owners with decat pipes who confirm that. Are modern motorcycle catalysers so restrictive these days?
 
Modern cats aren't as bad as they were before. But with that said high performance motorcycle engines are pretty much designed to produce maximum power and are actually designed to do so without a cat. So that tacked on cats in the exhaust really do restrict HP. Not only that but they're also trying to keep weight down so that cats are smaller than is ideal further increasing backpressure.

Now on a low powered bike like the NC, and like on a car, well weight is not nearly as big a concern so the cat is actually quite generously sized so it actually flows just about as well as a straight section of pipe with the amount of exhaust flow the engine is capable of. That is, it's designed as part of the whole system unlike sport bikes which they pretty much tack on after the fact. It's the same way with Harley Davidsons bone stock they're extremely restricted and a simple intake and exhaust swap yield such large improvements because the emissions and engine simply weren't designed to run together.
 
The LV link pipe is a single piece. Comes with the hole for the O2 sensor as well as a plug to close it if you decide to run without. Works well with the stock silencer. If used with the LV silencer, the back pressure feels not enough at low rpm, hence affecting torque. The full system feels irritatingly loud above 3krpm. If running without the db killer, it's deafening.
 
ray said:
The LV link pipe is a single piece. Comes with the hole for the O2 sensor as well as a plug to close it if you decide to run without. Works well with the stock silencer. If used with the LV silencer, the back pressure feels not enough at low rpm, hence affecting torque. The full system feels irritatingly loud above 3krpm. If running without the db killer, it's deafening.
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Far as I am aware all link pipes are single pieces or have I misunderstood you? The link pipe is the pipe that links the silencer to the exhaust system and is only fairly short.
 
ray said:
The LV link pipe is a single piece. Comes with the hole for the O2 sensor as well as a plug to close it if you decide to run without. Works well with the stock silencer. If used with the LV silencer, the back pressure feels not enough at low rpm, hence affecting torque. The full system feels irritatingly loud above 3krpm. If running without the db killer, it's deafening.
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So in your experience is there any performance gain from using the decat pipe with stock silencer?
 
TC3 said:
Far as I am aware all link pipes are single pieces or have I misunderstood you? The link pipe is the pipe that links the silencer to the exhaust system and is only fairly short.
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The LV cat eliminating link pipe is actually the exhaust header. See L.B.S. picture post above.
 
PCBlock said:
So in your experience is there any performance gain from using the decat pipe with stock silencer?
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Not sure. It does make the engine run cooler (radiator fan kicks in less) and the stock pipe sound better (slightly louder, deeper but not excessive).
 
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L.B.S. said:
Maybe I'm looking at it all wrong, but I confess to being puzzled by that schematic of the exhaust pipe. It looks like it has a bolt plug for the O2 sensor, thus giving the impression it's also eliminated from the equation, and if it is getting rid of the cat, why is there a giant cat-shaped cannister in the header pipe downstream of the O2 bung?
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It looks like a cat, but it's likely a resonator. Not a bad idea if you've already got a slip-on. If I bought a cat-less pipe for my bike I'd either want it to come with a resonator, or take it to an exhaust shop to have one welded in.
 
buckshot said:
It looks like a cat, but it's likely a resonator. Not a bad idea if you've already got a slip-on. If I bought a cat-less pipe for my bike I'd either want it to come with a resonator, or take it to an exhaust shop to have one welded in.
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I think it's just a fake cat, welded in to look like one. It's really loud in full system config. Attract too much attention.
 
ray said:
I think it's just a fake cat, welded in to look like one. It's really loud in full system config. Attract too much attention.
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Thinking about it, the addition of the cat lookalike will add significantly to the expense of manufacturing this pipe as there will be extra work with welding in the bigger piece etc etc. It would be much easier to simply bend a single pipe to shape ? I doubt very much if it is a fake cat under the circumstances. I will go with the resonator theory for now. I may also write to Accessori Moto and enquire as to the purpose of the canister. I suppose that would settle it.
 
Grump said:
Thinking about it, the addition of the cat lookalike will add significantly to the expense of manufacturing this pipe as there will be extra work with welding in the bigger piece etc etc. It would be much easier to simply bend a single pipe to shape ? I doubt very much if it is a fake cat under the circumstances. I will go with the resonator theory for now. I may also write to Accessori Moto and enquire as to the purpose of the canister. I suppose that would settle it.
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To make it look like a cat to the untrained law enforcer? The last time I put a wire through, it did felt like a continuous pipe. Maybe I'm wrong. It's probably better to write directly to LV Italy :)
 
I definitely want to look into this further. I saw someone say that their friend who did this had the ECU reset, how is that done?

-Jesse
 
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