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XB12SCG '08 /w performance exhaust & filter -> running RICH! Help!

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jesserontu

Member
Joined
May 1, 2018
Messages
7
I have had the bike about 2 yrs now.
It has Sebring exhaust (same as Remus?) and BMC airfilter (open airbox + breather re-route mods done).
To my knowledge the ECM has never been previously touched -> should be stock.
I feel that the bike runs fairly well with this setup.
But I have been worried that I am doing harm to the engine by running it with "stock" tune but having performance parts.
To my understanding this kind of setup would lead to LEAN running condition, since air is more "easily available".

So, I got the Buelltooth+ECMDroid and first thing I had a look at the AFV -> It was 84%.
This was already quite strange to me since I would have expected the system to try to ENRICHEN the mixture.
So the first question is: How can it be that the system (with the performance exhaust and filter) is running so RICH that
the ECM has to take 15% of the fuel?! This just doesnt't seem logical to me...
I also recorded a log and analyzed in Megalogviewer -> o2 seems to be fluctuating rapidly around the 0,5V point,
so it should be working correctly (assuming that the sensor is OK).

Ok, then I tried to run the bike with the tune-file (.xpr) I got from from Buelltooth for this setup.
The recommedation was to run it in open loop an so I did.
--> it ran like crap, sluggish acceleration and gas smelling. So I think it was running very RICH.

Then I went back to the stock tune and tried to run it in open loop as well, resetting AFV to 100%.
--> not running well, and gas smelling again...
Also I did a log with this setup and the o2 sensor confirmed that it was RICH, signal around 0,7V.

In my opinion, all these findings suggest that the bike is indeed running very RICH.

Does anyone here have an idea what could be the casue of this?
And how to fix it?
I am out of ideas... :(

Thanks!

XB12scg 2008
BUEOD
Buelltooth+ECMDroid
MegalogviewerHD
 
simply upgrade to HellFire "One-Percenter" complete exhaust system with wrap. it will cure all your ailments. 0:30 mark i start gettin' down to business for ya!

 

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Haha, Lunatic:up:

Hey Jesserontu: I would highly recommend fixing the bike before you continue to mess with the ECM.
The AFV the low is not a sign of a bad tune in a stock ECM, it's a sign you have a problem that needs to be fixed.
If you are able to get it to run well by doing that (unlikely) you will just be masking the problem that caused it in the first place.

Your next question will be "What could cause that", and the answer is a LOT of things. Hard to diagnose an unseen bike one thing at a time invariable jumping from one guess to another...:upset:

You can find the service manual for free at the same website you bought the Buelltooth, or at Buellmods.com. Follow the diagnosis flow chart for how it runs at 100 AFV.
 
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I rec the before mentioned Hell fire 1%er exhaust mated with a MAGA tuner. Great job Lunatic. 👍🇺🇸.
 
HellFire "One-Percenter" complete exhaust system with wrap
Haha that's insane! :D
I see how that is able to cure all the problems in the world...

What do your plugs tell you ?
Haven't seen them yet, unfortunately.
I know it would give valuable information on this but I have also understood they are very difficult to get to...
Is that true by the way? Haven't had time to look into that yet...
I think I must do that next..

The AFV the low is not a sign of a bad tune in a stock ECM, it's a sign you have a problem that needs to be fixed.
If you are able to get it to run well by doing that (unlikely) you will just be masking the problem that caused it in the first place.
Yes I agree, thanks for the verification.
And I also understand I might have a complex task ahead of me :upset:
But yes, my plan is to get to the bottom of it like you proposed.
I know there are many possible influencing factors in the ECM+sensors, but how probable do you guys consider a problem with the fuel pressure or injectors? To me those would be the simplest (mechanical) reason for too RICH mixture (too much fuel getting through with certain injector pulse width).
How frequent are these kinds of problems in these components?
 
I am *not a knowledgeable tuner, but have you talked with Dave at Buelltooth about your issue? There is a fairly common issue with certain 'race' configuration tunes where the closed loop area of the fuel table is richer than it should be. This causes the bike to pull fuel and results in the wholesale reduction of fuel cell values, often into the lower 80s, read as a percentage, across the entire fuel table.

It might be wise to talk with him since supplied your usb interface and tune. He has talked at length with me about this very phenomenon, so your question won't be coming out of left field for him.

As Cooter said, if you have an issue with the bike, you need to fix that before worrying about tuning; however, if you turn out to be like me - with a mechanically sound bike that still insisted on dropping the AFV to the mid 80s no matter what, you might be in the situation where you are literally fighting with your tune as a result of a region within your closed loop fuel values. Drop Dave a line. He really helped me out in this area, and my bike is running wonderfully as a result.
 
There is a fairly common issue with certain 'race' configuration tunes where the closed loop area of the fuel table is richer than it should be. This causes the bike to pull fuel and results in the wholesale reduction of fuel cell values, often into the lower 80s, read as a percentage, across the entire fuel table.

Yes, I have heard about this problem.

Actually I forgot to mention that, when I ran the bike with the "matched" tune from Buelltooth, I ran it open loop AND fixed the AFV to 100%. Thereby the system is not able to do the "reduction of fuell cell values across the map".
But like mentioned, it ran like crap...

So I think this further verifies that there is something wrong in the basic working of the bike, mechanical or in the DDFI system.

Do you guys have any idea what are the most common causes in Buells to have RICH mixture?
 
Yes, I have heard about this problem.

Actually I forgot to mention that, when I ran the bike with the "matched" tune from Buelltooth, I ran it open loop AND fixed the AFV to 100%. Thereby the system is not able to do the "reduction of fuell cell values across the map".
But like mentioned, it ran like crap...

So I think this further verifies that there is something wrong in the basic working of the bike, mechanical or in the DDFI system.

Do you guys have any idea what are the most common causes in Buells to have RICH mixture?

Copy - actually, I think you did mention it and I missed it....sorry.
 
The fact that...
when I ran the bike with the "matched" tune from Buelltooth, I ran it open loop AND fixed the AFV to 100%. Thereby the system is not able to do the "reduction of fuell cell values across the map".
But like mentioned, it ran like crap...
Means precisely this...

So I think this further verifies that there is something wrong in the basic working of the bike
 
Which is what he said (i.e. agreeing with you) something like five posts up (or six). Not sure why you need to repeat it again and again in successive posts.

I think he's reading you loud and clear, Cooter....which, by the way, is what I said as well when offering a thought (which was well-intentioned but off the mark)...i.e. fixing the bike, if it has an issue, is the top priority.

I think he's trying to get suggestions as to *how* to start that troubleshooting effort - thus the continued questions about what might cause the perceived (rich) condition.
 
I'm trying to help. I quoted myself, because:

1) He is still messing with the ECM (to no avail)

2) And I already told him how to diagnose it:

"Your next question will be "What could cause that", and the answer is a LOT of things. Hard to diagnose an unseen bike one thing at a time invariable jumping from one guess to another...

You can find the service manual for free at the same website you bought the Buelltooth, or at Buellmods.com. Follow the diagnosis flow chart for how it runs at 100 AFV."

He very well could have a ECM programming issue (like CL AFV targets are set too rich). But he is looking for the easy way out by "jumping from one guess to another..." and could mask a REAL issue with ECM tweaking simply by diagnosing in the wrong order.

Guessing (or hoping some random forum poster guesses right for you) will cost more money and definitely take more time.
 
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Yeah - but give him a bit of grace in that 1) he's coming here to ask his questions...and at least responding to you (and others), even if not using the exact words you'd rather him say, 2) he's said at least twice that he knows he has some kind of problem and agrees that is his priority, and 3) the way I read his very last question is an effort to at least pulse the crowd here for places to start looking in his troubleshooting effort. Perhaps someone has had this similar (or exact) issue before, perhaps someone can refine his efforts by suggesting he check x or y as they've previously found x or y to characteristically cause this kind of problem or symptoms.

For the record, there have been numerous instances with both the XB and the Blast over the past 5 years that someone has done just that for me....i.e. suggested checking 'x', given my symptoms and that person's long experience, which has saved me much time and energy and gotten me back on the road in minimal time. There have also been times when that is not the case (especially recently), and that has required me to do the correct 'long haul' method of troubleshooting and repair.

I agree with you - lacking any clear input on that front, he should do exactly what you say. I don't begrudge him the question, though - nor do I think he is disagreeing with you in principle (at least yet). But what do I know....not much.
 
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