You only want to use 14.6 when doing your tuning runs. It allows te software to acquire data from the o2 sensors. You don't want to ride with a 14.6 afr. It's too lean.

Optimum is 13-13.5.

 

That was good info about the VE tables. I thought that for the VE tables to adjust themselves during operation you need the cells to be set at 14.6.
Vic, you are saying make the runs at 14.6, and let the VE tables build, and then set the desired A/F to 13 ish?

Can you explain more about this:

 

Basically, yes. I'm certainly no expert but if it's anything like the TTS which I have done some reading on, then...

 

I had my bike dyno tuned by an independent shop. The guy was a trained HD tech who spent years working at the dealer and now works at a reputable indy. He spent about 3 hrs tuning my bike and it came out excellent. If I recall correctly, he set my AFR at 13.2.

 

But it sounds like if you do that you are running with the 02 sensors disabled. Or in an open loop all the time.

I hear what you are saying. Make enough runs, and collect enough data to with the CLB set to what you wish. Take the data to build the tables, and then then generate and update.
After you have updated your VE tables you should then lower the cruising blocks that would be closed to an open 13.2 ish.
I can do this, but it is my understanding that you want to cruise in 14.6 for fuel economy. Even says so on Dr. Dyno. Now take that as conversation, and not fact. I am learning here.
I have a question for someone who is fimiliar with the VE Tables in the SEST. Do the cells ever go green or red? I guess I could manually enter some data in to see. I am just wonder.

Makes sense to set the CLB, and the run the data to set the VE tables, and then run in open loop, but then you do not have any way for the VE to change due to engine and air temp to adjust your cruising idle, and fuel economy could suffer. Correct?

 

You are on the right track. You do not need to run "13.0" a/f to cool th eengine during cruise and light throttle. After you have the VE tables calibrated, use the CLB (closed loop bias) to bias the system CLOSED LOOP, slightly richer. The "power enrichment" areas at near WOT ( wide open throttle) do require a command A/F of between 13.4 to 12.8 depending on RPM! ( But again the only way to get that perfect is a dyno tune ). But you will be close if you set those high TPS ( load) open loop A/F ratios to 13.0.

But again, I would not set every speed and load to an open loop 13.2/13.0! You loose the advantage of closed loop to adjust for both temperature changes as well as changes in altitude, and FUEL! ( There is a large variation is STOICH a/f from even one brand to another, as well as the dreaded Ethanol content that is hard to avoid) The closed loop fuel control adjusts for all of those changes.

Additionally, there are several protection "MODES" in the software that are there for engine protection during "abnormal" operation or high temperatures. If you set everything to "OPEN LOOP" set A/F ratio, you loose those "modes" protection.

And running too rich at low load and cruise, will affect fuel economy for no good reason!!

( The CLB when set to near 720 will be approx. an A/F of 14.4 to 14.2 depending on the fuel's "real stoich". That is plenty rich enough to keep your engine cool.)

 

Awesome info. I understand a little more now, and I guess I was correct in my response to Vic about how running 13.2 across the board (in cruise) would disable the ability to adjust for the unexpected, or better said the inevitable.

My question now, FBRR, is can you adjust the CLB now that the tables have been calibrated? Or do I have to set the CLB, and then recalibrate the VE Tables?

 

The bias can be "adjusted" after you have the VE's done. But again, you don't want to push it too far. The 720 number I offered is about as far as I would go with the CLB.

That number is the switch point voltage for the O2 sensors between RICH/LEAN operation of the closed loop fuel control.
There are several good reasons why the actual fuel control doesn't work as effectively if you move that number too far!
( There are folks that have pushed it further, but they really don't understand the comprimise they are making to "controlled closed loop" fueling.) Without getting too technical, I will let it go and say 720 is the max. bias you should try to use!
Cheers

 

FBRR, you're definitely a wealth of knowledge. Thanks.

It's proof positive that days of just asking "what size jet do I need..." are long gone. You now have to become an electronics expert when dealing with the fuel injection.

 

I found this and saved it, intending to read it and try to understand it someday.

http://www.rbracing-rsr.com/downloads/tts_tuning.pdf

It's from TTS, which isn't SEST but it may offer some help in understanding different settings, etc.

Or not.

I'm a ways off from doing any sort of tuning so my need to read it is minimal, if at all.