2009 Buell XB12SCG, Runs rough when warm

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SU8ZERO

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Sep 5, 2024
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Hey all. So I have a very odd issue with a 2009 Buell XB12SCG that I cannot pinpoint the cause. I have looked around the forum a bit and cannot seem to find a thread describing the same issue. When The bike warms up it will run/smell rich, have a rougher idle and sometimes die. The issue only happens when the bike is warmed up and gets worse intermittently. We have sprayed the intake while cold and hot, found no change in rpm, disabled close loop and still no change, fuel pressure stays at 49~psi and AFV seems to be staying at 100. The bike has new injectors, O2 sensor, IAT sensor. The bike has a drummer exhaust and has a map from Revmo to match.
I have 2 data logs that we got from the bike running on a stand.
At 912.34 seconds on the "Stumble" file is when the bike started to run irratically after I blipped the throttle a couple times.
At 407.010 seconds of the "DIED" file is when the bike shut off on its own out of nowhere. I would appreciate any help diagnosing this bike as I am at my wits end with it.
Below is the link to the files.
https://drive.google.com/drive/folders/1221AoKqYwH1ypfUIPsN9tpEvp1dw7UNq?usp=sharing
 
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We were thinking that aswell. Unfortunately we do not have the original file from the ECM so cannot set the eeprom back to stock. I tried looking at buell mods and other places for a stock 2009 xb12 stock map but no luck. Any input on where to find a 2009 xb12 BUE1D stock map would be appreciated. My though is even with the drummer exhaust on the bike and a stock map, the bike should still fun relatively well, and if it did then it is infact a corrupt file and not a failing ECM.
 
@kz6fittycent , Understood, Thank you! Will try shortly and see what happens.

EDIT: The 09 Map was for a BUEYD ECM, IDs didnt match. Thank you again for the link though!
 
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What are you putting these logs into? I tried putting them into TunerPro 4 and it isn't recognizing them.

Let's break down what you have going on here:

When The bike warms up it will run/smell rich,

Yes, Buells usually have a very rich warm up cycle. It's one of the reasons why its not recommended to start the bike unless you're actually going to ride it. Starting it up, and just revving it up, is going to foul plugs. Luckily yours is a DDFI3 bike and it should be easy to manage that, but I see no mention of it (either through the ECM cleaning procedure or manually) so I will assume you're not.


disabled close loop
Why?

fuel pressure stays at 49~psi
How are you checking this? What do you mean by "stays at 49 psi"? Does it stay while the motor is off? While it is running? While you are riding?



and AFV seems to be staying at 100.
Is it actually staying at 100? The AFV is going to float around but should stay close to 100. But having it stay at 100, while optimal, is kind of odd. Unfortunately, I cant get your logs to work in my version of TunerPro (probably my fault-outdated)




The bike has new injectors, O2 sensor, IAT sensor.
Why new injectors? Were yours not functioning? Where did you get the injectors? Are you SURE the new injectors are working properly? It wouldnt be the first time someone replaced a part with a defective new part.

Same with the O2 and IAT sensors. Why?



The bike has a drummer exhaust and has a map from Revmo to match.
Could be the map is corrupted, but the "Rev Mo maps" do work. Maybe not everyones thing, but he does have a Drummer map you could reupload to see if the bike behaves better. You could even use one of the other maps if you feel his Drummer map is corrupted. Having the incorrect map is not going to cause the problems you are having, but should get you closer to a solution. If you don't trust his map, you can also contact IDS for a map, but they will charge for it (but its reasonable). There are lots of people running around with Buells (and other bikes) with a different muffler/air cleaner/whatever and never change their map.

I also see no mention of resetting the TPS. It's simple on a DDFI3 bike, so not sure why you wouldn't do that.


So, also noting

When The bike warms up it will run/smell rich, AFV seems to be staying at 100. The bike has new O2 sensor

If the bike IS running rich, the O2 sensor should be picking that up and adjusting the AFV to compensate. I see no mention of checking the values of the O2 sensor to see if it is even working (or not hooked up).

Unless the bike is stuck in its warm up mode and the ECM does not think the bike is warmed up yet. I don't remember if ECMDroid tracks this but I know ECMSpy does. I see no mention of checking to see what values the CLT sensor is providing. It wouldn't be the first time one of these failed and tricked the bike into thinking its running hotter/cooler than it actually is.


This whole post smacks of CoOter trolling us. Dammit! I know where you live... and stay out of my beer fridge!
 
Im hitting you back with the quotes!! :p I left out some info clearly so I will try to be sure I fill that in with the following.
The bike came to us from a guy who bought it from another guy who had it tuned buy another shop. The only part we have replaced was the IAT sensor due to it having incorrect resistance at a specified temperature.

What are you putting these logs into? I tried putting them into TunerPro 4 and it isn't recognizing them.
MegaLogViewerHD. I also have the logs in a .LOG file, will your program support that?


Luckily yours is a DDFI3 bike and it should be easy to manage that, but I see no mention of it (either through the ECM cleaning procedure or manually) so I will assume you're not.
No, I am unsure of what you mean by ECM Cleaning procedure or manually


Disabling closed loop, Why?
From my very basic understanding this would keep the bike running on a more "Preset" map without the ECM reading all the PIDs and compensating as much. Seemed like maybe if the bike ran better with closed loop disabled then the issue would be in one of the sensors that the ECM reads in closed loop. Again, I do not fully understand so this theory of mine could be WAY off.

How are you checking this? What do you mean by "stays at 49 psi"? Does it stay while the motor is off? While it is running? While you are riding?
With a Fuel pressure gauge inline while the bike is priming fuel pump and while running.



Is it actually staying at 100? The AFV is going to float around but should stay close to 100. But having it stay at 100, while optimal, is kind of odd. Unfortunately, I cant get your logs to work in my version of TunerPro (probably my fault-outdated)
Both AFV stay primarily at 100. Sometimes I have seen them 95-105 but usually they are at 100.



Why new injectors? Were yours not functioning? Where did you get the injectors? Are you SURE the new injectors are working properly? It wouldnt be the first time someone replaced a part with a defective new part. Same with the O2 and IAT sensors. Why?
This is where I left out some key info. This bike came to us from a customer, all this info was given to us from the customer and this info was given to him from the previous owner, so its a very bad game of telephone. We have no idea if the injectors, or 02 sensors were even bad and no way to get the old parts back. We did confirm the IAT sensor was bad through diagnosing it using the electrical diag manual. It has since been replaced.


Could be the map is corrupted, but the "Rev Mo maps" do work. Maybe not everyones thing, but he does have a Drummer map you could reupload to see if the bike behaves better. You could even use one of the other maps if you feel his Drummer map is corrupted. Having the incorrect map is not going to cause the problems you are having, but should get you closer to a solution. If you don't trust his map, you can also contact IDS for a map, but they will charge for it (but its reasonable). There are lots of people running around with Buells (and other bikes) with a different muffler/air cleaner/whatever and never change their map.
We have gotten a map from REVMO for the drummer exhaust. After putting this map on the bike, nothing changed as for as the running rich after it has been running for 5+ minutes. I agree in the belief that the map is not the cause of the problem, our though was get a stock map back onto the bike so that way we are as close to a baseline as possible for diagnostic purposes. Like you said, even people running exhaust, air filter and whatever without changing the map would likely run well. We will contact IDS to see if we can get a stock and drummer map but after trying 3 different maps and seeing no change I do not believe that the map is the cause.


I also see no mention of resetting the TPS. It's simple on a DDFI3 bike, so not sure why you wouldn't do that.
We did do that, I just forgot to mention. It sits at around 4
at idle, when it begins to run rich/rough this will change closer to 8


If the bike IS running rich, the O2 sensor should be picking that up and adjusting the AFV to compensate. I see no mention of checking the values of the O2 sensor to see if it is even working (or not hooked up).
Reading the 2 02Sensor values in ECMDROID, one of the PIDs stays at 0.49V. The other PID will slowly start to climb from about 0.5 and then when the bike starts acting up the 02 sensor will read from 0.1 to 1.1V

Unless the bike is stuck in its warm up mode and the ECM does not think the bike is warmed up yet. I don't remember if ECMDroid tracks this but I know ECMSpy does. I see no mention of checking to see what values the CLT sensor is providing. It wouldn't be the first time one of these failed and tricked the bike into thinking its running hotter/cooler than it actually is.
This is similar to our thought with the whole closed and open loop thing. Our thought is maybe the bike switch from being cold to warm and then when it switches is when it start to overcompensate. What is it compensating for or misreading is where we are lost. The CLT rose all the way to 422 and then dropped to 380 in a matter of seconds. Around this time is also when bike runs rough and the 02 spikes erratically from 0.3 to 1.1 and all in between. I also have the files in .log file, maybe your viewer would support that?


This whole post smacks of CoOter trolling us. Dammit! I know where you live... and stay out of my beer fridge!
This is not CoOter...or is it?!?!?!:tongue-new:
..Seriously though it is not a troll, just a guy looking at a buell on my stand that I do not understand :( Once again thank you!!
 
I was kidding about your being CoOter (and trolling us).


I don’t know why I didn’t run your files through megalogviewer. As soon as you mentioned it, I thought “Duh! What is wrong with me!”
The additional info is helpful to ruling out other possibilities. I will have to crack open my service book and see where your sensor values are. My bike (the Methbuell), used to jump around between warm up and normal. It’s been years since I’ve resolved it. I’ll have to put on my thinking cap.
 
graph.jpg
So looking at the data log file, the only weird thing im noticing is that the 02 sensor reading goes up pretty gradually until about.684 volts and then it becomes erratic, this is also when "EGO Corr" PID also begins to show up on the graph. From what ive read, the EGO is the bike making temporary fuel adjustments based off the 02 sensor while in closed loop.
 
^^^^^^^^^^^^^
Hesitant to recommend considering O2 replacement as this typically results in something along the lines of "Replaced O2 sensor as Barrett recommended and STILL NO CHANGE."

The amount of Applied Fuel Values cross-checking extraordinarily low and I've never seen generated voltage exceed the 0.565V range. Sure has the appearance of a failed O2 sensor.
 
^^^^^^^^^^^^^
Hesitant to recommend considering O2 replacement as this typically results in something along the lines of "Replaced O2 sensor as Barrett recommended and STILL NO CHANGE."

I will replace the 02 sensor and if the problem is not fixed i will find a bus to throw you under :p totally joking btw.

I was told the 02 sensor has already been replaced but whose to say that is true or if it was even replaced with the correct part. Is it not weird that the 02 sensor voltage just gradually increases? Or is this typical with the bike warming up? Should the 02 sensor not stay relatively steady with the ECM continuously adjusting the injectors, spark and IAC ?

Also to your failing ECM reply earlier, we are in talks of sending the ECM to IDS to program a different map aswell as test the ECM.
 
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Well, the bike still runs pretty bad. We had IDS put a good map onto the ECM and test the ECM, they said it was fine. We have also cleaned all of the grounds and swapped the O2 senser to a known good sensor. It is very odd, the bike will run well when it feels like and then out of nowhere the IDLE will drop, sometimes it does, sometimes it will come back up.
 
Ive had the bike running with a fuel gauge on the line right before it connects to the injectors, stays at 49psi, doesnt even move.(its actually impressive)
With a node light ive checked the injectors pulse aswell as visually inspected the wiring, no issues found. When the bike acts up, it smells very rich, when i check the injectors with a inspection mirror, they are dry.
Sprayed all over the intake with started fluid, no rpm change.
Im curious if the bike is making itself rich or is it just not combusting the fuel?
I also want to cry but thats besides the point.:sorrow:
 
"Im curious if the bike is making itself rich or is it just not combusting the fuel?"

If you think that's a possibility then simply perform a compression and leak-down test on both cylinders.
 
This might be a long shot, but I had a similar issue with the bike running rough and back firing.
Tried all sorts of things and in the end found a post about the grounding issues on our bikes,
added some new grounding to the engine mount under the airbox cover and the ignition coil directly from the battery and all my issues went away.
There are quite a few posts on various Buell forums about this.
Costs more or less nothing so no loss if it doesn't help ;)
 
I’ve got exactly the same problems with my xb12ss and also have replaced the same as you.
It’s doing my head in.
I haven’t changed the O2 sensor but have unplugged it and still the same outcome.
I have to change the plugs as they foul real bad.
I’m after advice too.
Bike has only done 11000 km
 
Is it not just a broken ignition coil? On a bike without fuel injection I would swap ignition coils on similar issues.
It can also explain the readings because the hotter the ignition coil the less ignition!
 
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