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Discussion Starter · #1 · (Edited)
I recently bought a 2016 CCT with 3,200 miles on the ticker with Vance and Hines exhaust. As far as I know the engine and everything else is stock. I disconnected the O2 sensors. Using pencil and paper, my last two gas receipts for mileage came out to 39.57, and 35.5. My 2012 XR would consistently get 45-48 MPG. I use non-ethanol gas 90% of the time.

We finished a 300 mile ride yesterday and noticed a lot of carbon on the LEFT exhaust tip. The right isn't as bad. My 2012 XR did the same thing but not nearly as much as this bike.

The bike runs fine and pulls strong. There is a LOT of rumbling from the pipes when I back off the gas. The bike sounds like a semi on the Jake Brake.

I'm going to pull the plugs and see what they look like.

What else should I look into to correct the carbon problem?

Thanks
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Well, you disconnected the fuel monitoring sensor...now it just dumps more fuel into the exhaust.

The left side flows more exhaust because of the design of the crossover pipe - normal.

Add a proper fuel tuner and really enjoy that bike
 

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Well, you disconnected the fuel monitoring sensor...now it just dumps more fuel into the exhaust.
This is patently false. The O2 sensors DO NOT CONTROL FUEL MIXTURE. They are not "fuel monitoring sensors" in any way. They answer a question asked by the ECU with a yes or no. They are basically switches.
 

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I don’t see what the problem is. The bikes ecu is set to run rich on wide open throttle. Under less than wot a little bit rich runs better than a little bit lean. Looks to me like you’re running pretty good, no problem.
 

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Discussion Starter · #7 ·
So.... Not to worry? Get a fuel controller? IF the bike has one installed, where would it be? Under the fairing or side covers? Re-connect O2's? It is a 2016 if that matters (I pulled the black wire on O2's)..
 

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So.... Not to worry? Get a fuel controller? IF the bike has one installed, where would it be? Under the fairing or side covers? Re-connect O2's? It is a 2016 if that matters (I pulled the black wire on O2's)..
I would not worry. That's point one. Getting or looking for a fuel controller is point two. What I see from your pictures and description doesn't alarm me at all, but you can't really diagnose how well tuned a motor is without actually tuning it. This question becomes will it run better with a tuner? Probably maybe. There is a chance it's running very close to ideal. There's a more likely chance that a proper tune will have it running better, and eliminate the popping on decal. Point three would be the O2's. Almost everyone I've read and talked to has seen a small benefit by disconnecting them. My advice has always been to disconnect and try it, if you don't think it's better plug them back in. In your case you can try the reverse. Once you tune, and some utilize new sensors, some methods do not, but once tuned it should be left as is.
 
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This is patently false. The O2 sensors DO NOT CONTROL FUEL MIXTURE. They are not "fuel monitoring sensors" in any way. They answer a question asked by the ECU with a yes or no. They are basically switches.
Are you freckin' high?!?!? Yes, it is a fuel monitoring sensor! It monitors the amount of fuel leaving the combustion chamber in the exhaust to report a rich or lean mixture in the combustion chamber. Monitoring the fuel mixture in the exhaust....is it a rich mixture or a lean mixture. It tells the computer to make a change...thats a fuel monitoring sensor!!!

But, I'm sure you're going to argue with me so you are "right" and I'm "wrong" so, I'll just leave my comments here and duck out of the thread. I see the OP already has the information he needs anyway.
 

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Yes, it is a fuel monitoring sensor! It monitors the amount of fuel leaving the combustion chamber in the exhaust to report a rich or lean mixture in the combustion chamber. Monitoring the fuel mixture in the exhaust....is it a rich mixture or a lean mixture. It tells the computer to make a change...thats a fuel monitoring sensor!!!
Actually, It monitors oxygen (O2) in the exhaust.
What you are saying would be closer to the truth if it were a full-time closed-loop system with wide-band O2 sensors... but it is not. The Victory FI system is only part-time closed-loop (mostly at steady cruising), the rest of the time the engine is being fueled off a fixed map and operated as an open-loop FI system.

Air Fuel A/F Ratio Basics | Wideband vs Narrow O2 sensor

"A narrow band o2 sensor is an oxygen sensor that is only calibrated to know three things. Rich, stoic, and lean. What I mean by this is that it only has a narrow window that it see's the air/fuel mixture through. The sensor can tell the computer when it's stoic. If it's not stoic, it can tell the ECU that it's either Rich, or Lean, but that's it. It doesn't really output any particular value other than that....

A wideband o2 sensor is much more sophisticated than a narrowband sensor, and can be relied upon to be used as a tuning tool. Wideband sensors not only are a lot faster acting in the reading, but can tell you the exact a/f ratio that the motor is currently at."

Your Victory motorcycle has narrow-band O2 sensors. Most of the time the O2 sensors are not used to determine the air/fuel ratio and do not control it.

Your statement,
you disconnected the fuel monitoring sensor...now it just dumps more fuel into the exhaust.
is false. That's not how it works. Disconnecting the O2 sensors simply keeps the FI in open-loop mode full-time. There will be no dumping of fuel into the exhaust or anywhere else.

Are you freckin' high?!?!?
Not yet... maybe later today.

But, I'm sure you're going to argue with me so you are "right" and I'm "wrong" so, I'll just leave my comments here and duck out of the thread.
It's not about who is right or who is wrong... it's about accurate information. There is no need to get all defensive and run away. Everyone wants the same thing... for the person asking to get accurate answers. It's not a contest.
 

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Ruh-Roh.....
 

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That soot means your having fun! Get a maximus tuner!
 

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It is true that all O2 sensors and fuel injection systems are not the same. Victory’s closed loop fuel injection system was introduced in 2008, previous years used an open loop system. Victory’s new in 08 closed loop system uses narrow band sensors that do VERY little. When a threshold is met, it sends one single signal. It is an on or off switch and that one signal tells the ecu wether to run in closed loop or open loop. The technology dates back to the 80’s and is outdated as F.
So why did Victory do this? The change from the 07-prior open loop system was working just fine. But they had to pass a new emissions test. This new test allows for the motor to warm up for a max of four minutes before the test is conducted. So the motor warms up in open loop, with a slightly richer (and safer) air fuel mixture. Before the four minutes is up the O2 sensors reach their threshold and signal the ecu to run in closed loop. Slightly less fuel in = less emissions coming out, bike passes the test. Why put a modern expensive new state of the art wide band O2 system in when you can pass the test cheaply? Besides, the test is done at steady cruise, the ecu already runs rich at wot.
Not everything Victory did to the bikes is for the riders benefit, just like not everything they put in the manual is for the riders benefit. Sometimes they do things to increase profit, or protect themselves from liability, or to satisfy a government test.
 
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This is patently false. The O2 sensors DO NOT CONTROL FUEL MIXTURE. They are not "fuel monitoring sensors" in any way. They answer a question asked by the ECU with a yes or no. They are basically switches.
And you would be wrong again. What happens when it's in closed loop? It tries to get the fuel mixture to stoich. It does this with feed back from the o2 sensors. That's the whole point of them.
 

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And you would be wrong again. What happens when it's in closed loop? It tries to get the fuel mixture to stoich. It does this with feed back from the o2 sensors. That's the whole point of them.
The feedback is very limited...
The point was that disconnecting them will not cause 'fuel dumping'. They are not fuel monitors, they are oxygen sensors that only see a small window of sampling... good, less, or more... and only when the loop is closed. Connected or disconnected will not be a cause of pipe soot and will not change the A/F under acceleration or at full throttle. The ECU basically uses them as switches, and only sometimes. The ECU does not rely on their input to operate and functions perfectly well without them... some would say better without them.

The only ones who think "stoich" is a good thing are the EPA.
 

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This is patently false. The O2 sensors DO NOT CONTROL FUEL MIXTURE. They are not "fuel monitoring sensors" in any way. They answer a question asked by the ECU with a yes or no. They are basically switches.
Hey Crazy. I don't know how to post a new question yet but I want ask you a question as you sound like you have been around...

Do you know of anyone who has modified a Straights exhaust? I'm thinking of cutting the length in half or slightly less to give it a different look. Baffles out, and thunder torque inserts in. You know of anyone who has done this? I have seen a guy who done it to his curved exhaust. I might get a Bassani turnouts look. I just spent $1000 on the straights so the wife won't let me spend more $ on a new one...so I'm getting creative. You think I'd run into any problems?
 
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