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Kinda putting the cart before the horse, but trying to understand the SERT prior to use in the near future.

1. I currently have software version "D" on the laptop with ver. "E" on the desktop. Also have ver. "F" ready to pick up from Dealer just in case. Some have said stick with the "D" version for 2005 bike as the later versions are "buggy". I see the "E" has provisions for '06 bikes including the closed loop Dynas. Manual appears to be same except includes '06 documentation. The '05 Touring Stage II file appears the same other than a different time/date stamp and file extension. Is there any solid advantage to using the newer software version?

2. Since I'll initially be using Advanced Tuning with the Data Record Mode, I'm a bit confused on whether to tune using AFR/VE vs. Spark Timing. The Manual reads:
Why Would I Want to Adjust the AFR?
If the ECM data recording shows an excessive amount of Knock Retard Activity when the engine is under load, it means that the ECM has detected detonation and is retarding the ignition timing to counter it. Detonation is an uncontrolled burn in the combustion chamber and it can be caused by a lean AFR.

Under: Why Would I Want to Adjust the Spark Timing? there is an almost identical statement that ends with It can be caused by spark timing that's too advanced.

Can anyone shed some light on which would be the "safest" approach to improving performance using AFR vs. Spark Timing?

:thanks:
 

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For maximum performance, you want to throw as much fuel at the motor as it will accept with AFR aimed at around 13:1 and adjust spark advance on WOT as advanced as it will go without ping/detonation. So this means you need real time AFR data.

What the manual is saying is that under the AFR section, if it is hitting the knock sensor, you can throw fuel at it to stop it. Conversely, in the Spark section, if you are hitting the knock sensor, you can retard the timing to make it stop. So, it's a balance of getting the most fuel in (through VE table adjustment) that the intake/porting will support in air content for an AFR of around 13 to 13.2:1. Then you test the motor under various load settings from WOT to various cruise regimes to get the spark advanced as far as it can go without hitting the knock sensor.

A dyno with a load brake, AFR sniffer and an operator that knows how to run the machine and the Race Tuner through it's paces to get the right balance will get the tune up idealized.

By the way, the first table is AFR, that is nothing more than a aim point for the software. It's the VE tables that actually control the pulse width of the injectors and hence the AFR. Your motors breathing ability(cam, porting, TB/intake, exhaust, etc.) will determine how much air can be ingested. The key is to get the AFR right for that amount of air at the different load/rpm's. then get the spark timing adjusted.

Hope this makes sense to you.
 

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Discussion Starter #3
Tot:

My initial impression was to richen the AFR via VE (safe) and then tread lightly with Spark Advance. So, yes your imput makes sense and is truly appreciated.

If you think of anything else to pass along to a (SERT) FNG,:huh: please do.

:thanks:
 

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Totenkopf said:
For maximum performance, you want to throw as much fuel at the motor as it will accept with AFR aimed at around 13:1 and adjust spark advance on WOT as advanced as it will go without ping/detonation. So this means you need real time AFR data.

What the manual is saying is that under the AFR section, if it is hitting the knock sensor, you can throw fuel at it to stop it. Conversely, in the Spark section, if you are hitting the knock sensor, you can retard the timing to make it stop. So, it's a balance of getting the most fuel in (through VE table adjustment) that the intake/porting will support in air content for an AFR of around 13 to 13.2:1. Then you test the motor under various load settings from WOT to various cruise regimes to get the spark advanced as far as it can go without hitting the knock sensor.

A dyno with a load brake, AFR sniffer and an operator that knows how to run the machine and the Race Tuner through it's paces to get the right balance will get the tune up idealized.

By the way, the first table is AFR, that is nothing more than a aim point for the software. It's the VE tables that actually control the pulse width of the injectors and hence the AFR. Your motors breathing ability(cam, porting, TB/intake, exhaust, etc.) will determine how much air can be ingested. The key is to get the AFR right for that amount of air at the different load/rpm's. then get the spark timing adjusted.

Hope this makes sense to you.
i just wanted to chime in, that was a very good explanation.i use the thundermax and am playing also, most people do not posess the communication skills you have.
you sir are an asset
 

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WVRDKING said:
Tot:

My initial impression was to richen the AFR via VE (safe) and then tread lightly with Spark Advance. So, yes your imput makes sense and is truly appreciated.

If you think of anything else to pass along to a (SERT) FNG,:huh: please do.

:thanks:
WV,
When I get my bike on a dyno, I use the SERT in the Data Log mode to record the pulls. Every pull is named by date and pull number so I can go back and review what happened, especially looking at the knock sensor for each cylinder. With the assistance of an experienced Tech, you can then analyze the AFR plot from each cylinder by getting the sniffer probe positioned in each exhaust pipe. Balance the AFR for each cylinder so they are both making equal power, then by looking at the torque/hp curves you can add or take away fuel at certain rpm points in the curve to get any dips squared away. Then start looking at the spark tables and make some adjustments to see if there is more hidden power lurking in there or to stop the knock sensor from being activated. My experience is that I have typically seen mine retard at most 3.5*. I then have gone in and backed the spark off about 1* to see if it stops the sensor from being activated.

Next time I get on the dyno, I'm going to get the WOT settings finalized for my bike and then start to work on the cruise settings with the dyno load brake set for resistance.

Once I get everything done, I will then load the notebook pc into one of my saddle bags hooked up in the Data Log mode and then record some data from street riding to be sure that the dyno settings are working properly on the street.

The bottom line is, it takes time to get it all sorted out but when done methodically, it will yield an optimized tune up for your motor.

Claydbal, thanks for the compliment! just trying to help out a little bit!
 
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