Understanding SERT tuning/data .
Thread Starter
|
Cruiser
Joined: Apr 2006
Posts: 123
Likes: 0
Understanding SERT tuning/data .
I posted this also on another forum. I am trying to learn all that I can....
Here is a question, trying to be sure I understand the SERT.
I have an '03 FLHT, 95" stage II, SE 203 and true duals.
I am playing with the tune to see if I can eliminate the surging at low Map and low RPM and maybe improve the MPG (only about 34 on the road). I have been playing with maps and data modes, excel spread sheets and data modes and seem to be making no progress.
I have thought about it and....
Since there is no feeedback loop on this system -- AFR to ECM, I suppose there is really no way to effectively tune. All data collected in "data mode" must be calculated based on the table input that I assign to the file. I am guessing that the ECM takes the TPS and RPM and does a table look-up to determine Injector pulse, and timing. It probably also takes the engine temp and does some other look-up for cold conditions or hot conditions.
Either way, the data out (collected in data mode on the SERT) is the result of the look-up and then somes calculation. If this is the case, then what value does a SERT have without a dyno and AFR data?
Maybe I am soaked and need to go back and read the manual again. I suppose that with some device that read AFR and collects data at TP and RPM, the bike could be tuned without a dyno. But this then would take a ton of time.
Only logical option would be to start off with a close map and run the bike on a dyno for about 8 hours.....
Anyone care to straighten me out...provide some feedback. Can the garage mechanic with basic tools really tune a bike using a SERT? And can it be tuned to run better that the std HD maps that are provided with the SERT?
Here is a question, trying to be sure I understand the SERT.
I have an '03 FLHT, 95" stage II, SE 203 and true duals.
I am playing with the tune to see if I can eliminate the surging at low Map and low RPM and maybe improve the MPG (only about 34 on the road). I have been playing with maps and data modes, excel spread sheets and data modes and seem to be making no progress.
I have thought about it and....
Since there is no feeedback loop on this system -- AFR to ECM, I suppose there is really no way to effectively tune. All data collected in "data mode" must be calculated based on the table input that I assign to the file. I am guessing that the ECM takes the TPS and RPM and does a table look-up to determine Injector pulse, and timing. It probably also takes the engine temp and does some other look-up for cold conditions or hot conditions.
Either way, the data out (collected in data mode on the SERT) is the result of the look-up and then somes calculation. If this is the case, then what value does a SERT have without a dyno and AFR data?
Maybe I am soaked and need to go back and read the manual again. I suppose that with some device that read AFR and collects data at TP and RPM, the bike could be tuned without a dyno. But this then would take a ton of time.
Only logical option would be to start off with a close map and run the bike on a dyno for about 8 hours.....
Anyone care to straighten me out...provide some feedback. Can the garage mechanic with basic tools really tune a bike using a SERT? And can it be tuned to run better that the std HD maps that are provided with the SERT?
Road Master
Joined: Mar 2007
Posts: 1,177
Likes: 23
RE: Understanding SERT tuning/data .
Without AFR data and better graphing software, it is almost impossible to make heads or tails out of the data off any of the systems available to the Harley world. The 02 equiped bikes and the use of third party graphing software specific for EFI datalogong makes home (part throttle) tuningquite possible. I have see some really serious holes even in the maps of a totally stock bike so even the factory has sometrouble getting a great tune on these things.
AW
AW
Outstanding HDF Member
Joined: May 2007
Posts: 2,304
Likes: 31
From: Florida
RE: Understanding SERT tuning/data .
Never seen or heard of the factory tuning there bikes before they go out the door. There is a basic map for the model bike and test run on the rollers and then out the door, thisis what you mignt see holes in the maps.
Gearhead
A good dyno operator and SERT tuner can dial in your bike in 4 to 5 hours and thats time taken to load and unload on and off the dyno. Trying to do this with out the proper data (Afr feed back under a load in a controlled environment) will be wearing out the tires before you get a tune.
Gearhead
A good dyno operator and SERT tuner can dial in your bike in 4 to 5 hours and thats time taken to load and unload on and off the dyno. Trying to do this with out the proper data (Afr feed back under a load in a controlled environment) will be wearing out the tires before you get a tune.
Road Master
Joined: Mar 2007
Posts: 1,177
Likes: 23
RE: Understanding SERT tuning/data .
Every vehicle comes out of the factory with a standard map (or tune) that was setup to work on the "average" bike and pass EPA testing requirments. That factory tune has a few fairly large holes in it. Granted I had recently changed pipes back to the factory pipes and the factory ECU may have not fully homed back in at the time of the data log. I could post logs here if people want to see them after the bike has enough miles on it, to see how the o2s and the fuel corrections are doing.
AW
AW
Thread
Thread Starter
Forum
Replies
Last Post
jrudicel
Ignition/Tuner/ECM/Fuel Injection
2
May 27, 2007 05:38 PM
