ECMspy, Direct Link, and other "tune" guru's.......I have some theory/fundamental questions

[g4string]

So I started reading through the "ECM Tuning Notes for Buell DDFI and DDFI-2 2nd Edition" (found here - http://xoptiinside.com/tuning_guide). This is my 1st step at starting to learn and understand the tuning process. However, after reading it, I must admit I have some questions as to why we need tune in regards to the way the ECM actually works. Hopefully, I know enough to explain myself and state my questions in a way that makes sense;


So as I understand it, and the way the manual states it, the ECM found on all Buells operate under 4 conditions;

close loop (CL)
close loop learn (CLL)
open loop (OL)
open loop wot (OL WOT)

The book states that ALL ranges are defined by TPS position and RPM. This would mean that there are definitive boundaries for all 4 modes. Easy enough....

During close loop, the o2 sensor is in charge of maintaining the proper AFR. It is striving for a stoich mixture. In CL, the ecm will automatically adjust itself to maintain stoich.

In CLL mode, the same things apply as in CL mode. However, in addition to that; the ecm is setting it's adaptive fuel value. The AFV is what is applied when operating out of the CL range.

In the OL mode, the AFV values are put in place in lieu of the o2 sensor monitoring ego. Since the AFV is "adaptive", vaules can/will change. However, (if I get this right) the value will only change unless the ecm goes back to the CLL range. At that point, the ecm obtains/updates the AFV parameters.

In OL WOT, same thing happens as the OL mode except ecm will create a more rich mixture for power where OL is more lean to decrease popping on decel, for effective engine braking, and to ensure a quick return to idle.

What I dont understand is that if the ecm is always learning and adjusting, then why do we need tune it?? I mean, while in CL and CLL mode, we "should" have no worries as the ecm is in continuously monitoring ego and making the needed corrections as need be. During the moment that you drop in to the CLL mode, the ecm is setting up the AFV. The AFV that the ecm just learned is "today, in the moment, right here, right now" specific. So why wouldn't the AFV parameters be good enough for fuel metering when one is out of CL mode. After all, the ecm just learned it? So the way I see understand it, what good does tuning do us after intake and exhaust mods if the ecm has the capability to compensate for the changes we made with said mods?? I am confused.....please help me understand!!!

 

[dallasb]

The ecm is only capable of raising or lowering the entire map. It can't flatten hills or raise valleys. The idea of the tune is to match your bike with its environment (be it mods or just at a different elevation then that of Michigan). Having a good tune will result in a motorcycle with more power, sharper reacting, and overall smoother running motor.

 

[brightbuell]

Let me get this straight if I set my AFV values both to 100 and box it in/ disable it, under certain conditions when it needs it can still adjust its self? Im asking this because thats what it feels it like when im riding. My AFV values are set to 100 and I have a map from Theoctopus. Before I changed the AFV values it would begin to run a little lean once hot. After I changed it would not begine to run lean once hot and runs great all the time. Much more HP. torque and much better gas mileage. Its consistaintly great all the time and it seams some people dont believe that its posable that my bike is running great with both AFV values set at 100.

 

[theoctopus]

Your O2 is only a narrowband. If your bike is running outside of those parameters, your ECM is not able to adapt appropriately.

The goal of a tune is to get the perfect maps for your environment, and then give the ECM some leeway to make slight modulations from those values for varying environments. That way, when you're riding in your hometown, your bike runs perfectly. When you go on longer trips, the bike has some room to change for the different conditions.

 

[brightbuell]

close loop (CL)
close loop learn (CLL)
open loop (OL)
open loop wot (OL WOT)

So the ECM is still learning wether or not my AFV values are set at 100. But under one or more of the conditions its locked /boxed from adjusting its self. Open loop WOT is apparently able to adjust its self on demand even though my afv values are boxed/ disabled.

Does this make sence. If I reopend my values to what they were when I first got your map then run the bike till hot, untill its running rich or lean, what ever its doing, hook up to the bike and fetch my values to see if its high or low thats causing my crappy mode, then adjust either the bottom up or the top down a bit so it cant force its self into that crappy mode. Then it would be able to adjust the other way when needed just not they way thats causing the problems. This would solve my issues here and I could set it to default when I go on road trips to higher elivations.

 

[brightbuell]

Also if im lucky the direction I leave open might be the direction that my bike would need to adjust for higher elivation. Its going to be one way or the other.

 

[theoctopus]

Keith, unfortunately this is an impossibility. The ECM does not adjust specific values. There is no way to look at an "adjusted" fuel map post-running.

The only solution is for you to tune specifically to your environment, and then unlock the AFV to allow for some room to breathe.

 

[Jabaniz]

And please don't forget to unlock afv after tuning. And remember that if you tune to 100afv one day it could easily change depending on weather, barometric pressure, and tempature. For me, I strive for a smooth run through my throttle, decent mileage and nice starts
The hard part is I live in NoDak and temp changes can be from mid 90's to 50's in a day so I'm happy to get it smooth. I'd rather ride than tune. Now that fall is coming I might do a few logs in cooler temps and see where I am

 

[g4string]

So I spoke with Al at ASB. I have to say, I am still confused as to why we need to tune in CL and CLL mode. One thing he mentioned was that CL and CLL tuning were the most important areas to tune. To me, this made absoltuely zero sense. I mean, why tune in an area that is constantly adjusting and tuning itself. We did talk about some wideband/narrowband stuff. That stuff makes some sense. He did mention that one of the best ways to tune with a single narrowband o2 sensor is getting a preadusted map with your mods already logged....and then fine tuning the CL and CLL areas. And again, that makes sense. What I am still strugling with is understanding why tuning in the CL and CLL areas is the most inportant and even necessary? Sorry to be a stupid PITA....but f***, I just dont get it.