I have recently installed a PCV with the Auto Tune modules that include Wideband O2 Sensors. I got a great basemap from Jamie at Fuel Moto but I just don't know how to leave well enough alone...I think some of you understand.

I am working on two seperate maps. One for power/cooling. One for Fuel Milage while retaining the power/cooling in the upper RPM's and Throttle Positions.

My question is about optimal AFR's for different situations on my 2009 Street Glide. What's best AFR for power/cooling. What's best for mileage without burning a hole in a cylinder? What if I add an oil cooler...what AFR's then?

So far the autotune modules will tune the bike just fine for whatever AFR's I dictate but to this point I've been flying blind and guessing at what would be good at different RPM's and Throttle Positions. Any help anyone may provide would be greatly appreciated.

 

If it aint broke fix it...I know the feeling

 

For power the you typically see around 13.3 to 13.7. You can go way low for cooling. The TTS MasterTune maps go as low as 12.0 (or lower) in the PE maps. Power Enrichment is the ability to add fuel as more time is spent at WOT.

For econ 14.7 should be the max. I would prefer less but don't have any specific data to provide yet.

If you look at TP and RPM while riding you will begin to figure out where you need fuel economy and where you need power. I believe you can have both in one fuel map. I put some tape on the throttle and marked off 10%, 20% and 50%. Then rode a while paying attention to TP and RPM.

If you are working on fuel economy you will find the RPM range to be in the 2000-3200 range. Lower if you have a six speed trans. You will find TP setting around 10% to 20% or less. My suggestion, make the cruise range around 14.4 AFR and blend down to 13.3 as you go to WOT.

Why worry about fuel economy beyond about 42 MPG. You are just running the engine too lean and hot. My boat consumed about 50 gallons per hour at WOT. Why worry about a bike. You are already very effiecient.

B

 

OK I made a few adjustments to target AFRs and test rode. Seems just fine to me. Good mileage in cruise and plenty of power elsewhere. Take a look at my new target AFRs and tell me what you think...