A/F Ratio Changes w/ Stock Map

[bagman]

Looking at the stock maps, the A/F table ratios are 13.25-15.5. Reading through what I can find between Tuneboy & TuneECU, 12.8-13.5 is the best for power.

Has anyone tried the stock fuel & ignition tables with modified A/F table changes only?

Or will the fuel & ignition tables need changes to match?

 

[warp9.9]

It will work as there are two ways lie to the F table telling them there is more air in the cylinder which force the ecu to recalculate or change the fuel ration and force the ecu to recalculate. If you not building anything in the motor and you do not have a dyno to put the bike on before and after you won't feel the difference leaving the timing where is.

 

[Power-Tripp]

The AFR tables are only used when the Keihin ECU is in closed loop - idle, cruise, under ~6-8% TPS. The narrowband Lambda sensor simply does not have much range. As a result, the AFR table des not do what you think it should.

I hope this helps.

 

[kmrmike]

power-tripp...Iwonder if you could explain a little more-I'm new to the forum and am waiting on my cable for TuneECU

 

[Power-Tripp]

EFI basics

This is not an automotive type ECU/ECM/PCU, with more advance tuning solutions than TuneECU/TuneEdit. The Keihin ECU is a simple unit using a limited number of sensors, with limited speed and memory. Just look at how injection, cam, and ignition events are controlled (or not) - resoultion and accuracy are not as advanced as with most modern automotive engine management systems. This is a cost issue.

The AFR table can only work within the abilities of the ECU and the narrowband Lambda sensor. If you understand how narrowband sensors work, you can understand their limitations. As a result, closed loop control only occurs at low throttle openings from idle through cruise, even though the table shows a much broader range.

Fueling occurs based on the look-up tables for each cylinder as well as the offset trim tables. These tables are based on throttle position (TPS) and manifold air pressure (M AP) over rpm, to determine load and engine speed. Since this engine uses individual throttles for each cylinder, MAP is the predominant table for fueling and ignition advance at lower rpm (for increased resolution), and this changes as engine speed and load increases, until the TPS-based tables take priority. Priority is assigned/altered with the F_L Switch table.

I hope this helps.

 

[kmrmike]

Power-tripp, thanks for the explanation of the system...Is there more information available In using the tuneECU system without putting a burden on the folks on the forum? I used another system in the past using a laptop and downloading to a vehicle which I had installed a turbo, fuel injection, crank trigger Ign. etc....but each system is a little different and I'd like to gain a little more education & confidence before making any changes. My radical changing days are over but I still like to play with technology.

 

[Power-Tripp]

Do a search on the R3Owners forums, as well as the Rat forum for tuneboy, tuneEdit, and TuneECU. There is a good amount of information on mapping with TuneECU and TuneEdit on other forums for Daytona 675, Speed Triple, Tiger, and Bonneville/Thruxton as well as for KTM, Ducati, and Aprilia models. The Daytona and Speed Triple 955cc models use the Sagem ECU and this differs considerably from the Keihin bikes.

Compared to the tuning solutions and interface software for automotive use, or aftermarket engine management, TuneECU and TuneEdit are fairly simple if you've ever mapped a car with individual runner throttle bodies (IR or ITB). With less access to tables - especially sensor tables, acceleration compensation, injector timing, coil dwell, etc., etc.. And no cam sensor to consider.

The "L" tables are MAP based, the "F" tables are TPS based. Different maps allow differing control of ignition mapping based on MAP and TPS. The "F_L Switch" sets MAP/TPS priority at different engine speeds - same as any other setup for Alpha-n with IR throttles. The AFR table is discussed in posts above. The Idle table is engine speed at differing engine temps in °C.

You also have the ability to adjust speed limits, rev limits, secondary throttle opening, speedo corrections, fan thermostat switch, and more.

Different maps and different models allow differing amounts of control of other features - exhaust throttle (ExUp valve), intake flap valves, Lambda sensor, SAI servo, etc.

I hope this helps.

 

[kmrmike]

Thanks again...Guess I have some research and much reading to do!