SERT AFR Desired ?

[Crockett]

On a SERT you can read the parameter "AFR Desired" (AFR Command in Twin Scan).
Can someone tell me how the ECM comes up with the AFR Desired that you see in Data Mode
Im curious what variables effect this and how the ECM uses the data on a bike with no O2 sensors ?

[wolf_59]

I'm pretty sure that is what your ECM is programed for, it is not reading your actual AFR
From what I have gathered from using my TTS you set your desired AFR in the table and then adjust your VE's to make make those AFR's actually happen, To do so you need to be able to read your actual AFR's with an O2 sensor and meter

I'm only a beginner so maybe one of the more experinced guys will respond

[Crockett]

Wolf
There has to more to it then you have mentioned
You would think by the title that the AFR Desired would be a setpoint that you enter although it is contantly being changed by the ECM.
My question is what is the ECM basing these changes on and how it affects the tables.

Thanks for the reply

Scott

[wolf_59]

I'll try to attach this maybe it can explain it better

[attachment removed after 60 days by system]

[FLTRI]

On a SERT you can read the parameter "AFR Desired" (AFR Command in Twin Scan).
Can someone tell me how the ECM comes up with the AFR Desired that you see in Data Mode
Im curious what variables effect this and how the ECM uses the data on a bike with no O2 sensors ?

Once the VE tables-to-actual AFR have been precicely calibrated to a base of say 13.2 with the AFR table set to 13.2, the AFR table will recalculate the actual AFR t o the AFR table's target.
The fact is the VE tables must be properly calibrated on a dyno in order for the software to recalculate a change made in the AFR table.
Since no 2 engines (injectors) are the same the stock VE tables are not that close to begin with. Then change the cams, exhaust, or anything else and the VE tables are not even in the ball park so changes to the AFR table will not net predictable results.
The tailpipe AFR is calculated from proper VE calibration and cannot work if the calibrations are not spot on.
I have a lot of customers come in with really messed up running engines because they thought all they had to do was change the AFR table and the software would auto adjust to the target......wrong.
HTH,
Bob

[Crockett]

" I'll try to attach this maybe it can explain it better "
Thanks Wolf...good info in there.

[Crockett]

Thanks Bob For the info

On a SERT you can read the parameter "AFR Desired" (AFR Command in Twin Scan).
Can someone tell me how the ECM comes up with the AFR Desired that you see in Data Mode
Im curious what variables effect this and how the ECM uses the data on a bike with no O2 sensors ?

Once the VE tables-to-actual AFR have been precicely calibrated to a base of say 13.2 with the AFR table set to 13.2, the AFR table will recalculate the actual AFR t o the AFR table's target.
The fact is the VE tables must be properly calibrated on a dyno in order for the software to recalculate a change made in the AFR table.
Since no 2 engines (injectors) are the same the stock VE tables are not that close to begin with. Then change the cams, exhaust, or anything else and the VE tables are not even in the ball park so changes to the AFR table will not net predictable results.
The tailpipe AFR is calculated from proper VE calibration and cannot work if the calibrations are not spot on.
I have a lot of customers come in with really messed up running engines because they thought all they had to do was change the AFR table and the software would auto adjust to the target......wrong.
HTH,
Bob

I guess i should have mentioned that i am using a Sert for Data Mode only.(It isn't married to my bike)
I am using a PCIIIr at the present time so my options are limited .
So can the VE, AFR, and Timing Tables all be fully modified when tuning with a SERT?

[Steve Cole]

Yes, and more too.

[Crockett]

Yes, and more too.

Thanks for chiming in Steve but could you elaborate a bit more.
I have a Older SERT i could install but i havent used one in tuning mode yet.
I would hate to go install it just to decide to switch to TTS
I dont have permanent O2 sensors so im not sure the TTS would do that much more for me than the SERT.
Obviously the tuning modes are different but is there any difference in the data mode of a sert compared to the data mode of the TTS ?

[Steve Cole]

Since you have an early bike without O2's the SERT will work fine. Mastertune has been set up to work with the old SERT files for those bikes at this time so your not going to gain anything currently. That may change if there is enough interest for us to go back and update those bikes. The extra features do help but it all depends on what your looking for from you bike. If it just a good daily rider then use what you have. If it's braging over that last little bit of power then MAstertune would help.

[wolf_59]

Steve your killing me man, lol I hoping you would be announcing any day now that you had it all figured out so we could use the V-tune on our older bikes
Keep us posted if you do

[Steve Cole]

We are currently working on that for the 2005 and newer but no work on anything earlier than 2005 at this time. Once we have the 2005 and up done we will see how those go before looking at anything earlier. It's also getting close to new (2010) bike release so we are going to have our hands full of getting things figured out for the new ones soon enough as well.

[Ardy]

Steve, is it possible set up VE tables on a 2008 FLHT with a SEST without a dyno tune? I would like to do it myself.

Let me add that up until now I have only pipes and big air.

[Steve Cole]

We do not work with the SESPT so I could not answer that. I would ask people who work with that tuner to get a correct answer, try FLTRI as I believe he works with those.

[eddfive]

Not FLTRI but if you read his post again on April 4th you would need to have a way to verify the actual AFR reading to calibrate the VE tables.  Can this be done without a dyno, sure.  It may cost you some money to get the tools to do the job.  The quickest way though would be on a dyno as it will get data in all the areas needed to calibrate the VE table to a known AFR.  There would be a cost associated with this as well.

[ToBeFrank]

Steve, is it possible set up VE tables on a 2008 FLHT with a SEST without a dyno tune? I would like to do it myself.

Let me add that up until now I have only pipes and big air.

Yes, I have software that will do that.

[Ardy]

Thanks eddfive. I should wear my full face helmet around the house so I don't lose any of the limited brainpower I have left ...but I understand now.

Thank You
Rick

[Ardy]

Steve, is it possible set up VE tables on a 2008 FLHT with a SEST without a dyno tune? I would like to do it myself.

Let me add that up until now I have only pipes and big air.

Yes, I have software that will do that.

Would you share?

[FLTRI]

Yes, I have software that will do that.

TBF,
Are you telling us this because you will offer it for members to use to tune their bikes?

[ToBeFrank]

Yes, I have software that will do that.

TBF,
Are you telling us this because you will offer it for members to use to tune their bikes?

Yes, I have several people that have already used it. One (two if you include myself) was/is tuning using widebands, the rest were tuning using stock narrowbands with the SEST. It will even work with the old SERT if you have a closed loop bike.

[ToBeFrank]

Would you share?

Sent you a PM.