Fuel map AFR questions
I think I may be misunderstanding something: After some online research and reading I understand that the target afr needs/must be below around 14.7 or something like that. My target AFR's seem to be between 12.9 and 13.8. When I sent my map to fuel moto I had the intentions of going a bit leaner on my AFR's. When I received my new map I first brought it up in the house to compare tables but couldn't pull up the AFR tables for some reason. Anyway I then connected to my PCV and got the map from it and checked the Autotune trims (I have been leaving that on until I feel tuned, haha) and the AFR tables again. Then I opened the new map and discovered that I could then view the AFR tables. Now I am confused because they look exactly the same. I also compared the fuel tables of both maps and they were also the same. To me it looks like I received the same map back. Maybe this was a mistake or I am missing some information on how to calibrate the afr tables. I didn't feel comfortable in doing this myself and is why I sent to Fuel Moto. Again, I am on a 2005 RoadKing with Andrews 21 cams, stock 88ci displacement, and Dragos Dragula 2 into 1 pipes. I run PCV with autotune. Any help is appreciated.
Not far but I'm trying to learn as much as I can and do as much myself without paying for a dyno tune.
14.7 (14.6 for the SEPST) is an indicator that the bike should run in closed loop mode which means it will adjust its AFR based on reading from the narrow-band O2 sensors.
Your actual Target AFR is never that lean, else you'd burn your engine up in no time.
A lower / richer AFR number means more fuel, it also means slightly less fuel economy but often an enormous reduction of heat. Less hear is a very good thing. I run my bike with a mid-range target of 13.1 and it had great power, much lower heat and decent fuel economy.
HD ships these bikes with the AFR very lean to satisfy EPA regulations. They also run dangerously hot.
The range you stated of 12.9 - 13.8 is actually a very wide range and not something you just arbitrarily set. Depending on throttle position and RPM your ideal AFR should vary, sometimes quite a bit.
Good for you for learning this on your own, I went the same route. I began with HD's SEPST and dialed it in as best as it allows. Then I took it to 2 different dealers in KC (Rawhide and Blue Springs), neither did anything amazing for me and I suspect that the "tuner" at Rawhide actually does nothing. Both failed to point out a problem with my clutch that was robing me of both torque and hp.
I went with a ThunderMax for several reasons and now feel like I'm really getting the most out of my bike.
AFR is only one piece of the puzzle, timing place a big role in power, economy and health. It's hard to really dial in the timing without a dyno table. The T-Max makes it a little easier because I can load up 5 different maps with progressive timing changes and switch maps on the road without my laptop. It's still only seat of the pants, but it has made a difference.
Your actual Target AFR is never that lean, else you'd burn your engine up in no time.
A lower / richer AFR number means more fuel, it also means slightly less fuel economy but often an enormous reduction of heat. Less hear is a very good thing. I run my bike with a mid-range target of 13.1 and it had great power, much lower heat and decent fuel economy.
HD ships these bikes with the AFR very lean to satisfy EPA regulations. They also run dangerously hot.
The range you stated of 12.9 - 13.8 is actually a very wide range and not something you just arbitrarily set. Depending on throttle position and RPM your ideal AFR should vary, sometimes quite a bit.
Good for you for learning this on your own, I went the same route. I began with HD's SEPST and dialed it in as best as it allows. Then I took it to 2 different dealers in KC (Rawhide and Blue Springs), neither did anything amazing for me and I suspect that the "tuner" at Rawhide actually does nothing. Both failed to point out a problem with my clutch that was robing me of both torque and hp.
I went with a ThunderMax for several reasons and now feel like I'm really getting the most out of my bike.
AFR is only one piece of the puzzle, timing place a big role in power, economy and health. It's hard to really dial in the timing without a dyno table. The T-Max makes it a little easier because I can load up 5 different maps with progressive timing changes and switch maps on the road without my laptop. It's still only seat of the pants, but it has made a difference.
There are hundreds of thousands of bikes running 14.6 or leaner and have been for millions of miles. If you can provide a proven example of a bike that's "burnt up" because of that AFR setting, please do.
FWIW, the melting point of aluminum is about 1200*F, cast iron about 2100*F, and regular carbon steel about 2600*F.
While the combustion process in our normally aspirated HD engines can produce very specific cylinder temps high enough to melt aluminum, it does so in such a concentrated area for such a short duration that the normal 4-stroke design easily handles the heat with virtually no harm. In fact, the combustion process actually requires these high temps to even operate.
...A lower / richer AFR number means more fuel, it also means slightly less fuel economy but often an enormous reduction of heat. Less hear is a very good thing. I run my bike with a mid-range target of 13.1 and it had great power, much lower heat and decent fuel economy...
Now a slightly richer AFR may reduce some heat but that has been demonstrated to be something less then 5 degrees. If the average rider can perceive that little temp change, they should be working for NASA.
But if you're suggesting an AFR setting of 14.6 or 7 is cause for alarm and will result in damage (to something other then your skin or gear), that's just false. Again, there are far too many stock bikes with thousands of real road miles that indicate otherwise.
And modern metallurgy just doesn't support that theory.
This one I completely agree with...but it is only beneficial when the one learning is learning true and accurate information.
I think you have studied this to some degree but much of your retention is based on incorrect info or you have misinterpreted what you've read or heard.
Thank you all for the information. All of which is helpful. Anyway I learned that in order to view my AFR tables when not connected to the bike, I had to go into environment options and select "show auto tune tables even if power commander is not auto tune enabled".
I had already had a pretty good "grasp" for how this thing worked, but was kind of led astray by misunderstanding where the AFR tables came from after misunderstanding some information I read. I was right in the beginning that the AFR tables are user generated. What I would like to know is how am I too know what the "optimal" AFR is for each RPM/throttle position range without extensive dyno time?
FM did send me a new map today and apologized for missing where I indicated I was using auto-tune. Thanks for you excellent customer service.
I had already had a pretty good "grasp" for how this thing worked, but was kind of led astray by misunderstanding where the AFR tables came from after misunderstanding some information I read. I was right in the beginning that the AFR tables are user generated. What I would like to know is how am I too know what the "optimal" AFR is for each RPM/throttle position range without extensive dyno time?
FM did send me a new map today and apologized for missing where I indicated I was using auto-tune. Thanks for you excellent customer service.
Ultimately, you'll have to decide what you want out of the bike...performance (and where i.e low end, middle, WOT), economy, or longevity.
But a very highly skilled rider should be able to dial in a tune based on their experience and understanding of the HD EFI system with little to no use of a dyno.
Good luck!
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This is one of the short comings of using an "auto tune" type system as the algorithms are the result of someone else determining what THEY think is best or safe.
Ultimately, you'll have to decide what you want out of the bike...performance (and where i.e low end, middle, WOT), economy, or longevity.
But a very highly skilled rider should be able to dial in a tune based on their experience and understanding of the HD EFI system with little to no use of a dyno.
Good luck!
Ultimately, you'll have to decide what you want out of the bike...performance (and where i.e low end, middle, WOT), economy, or longevity.
But a very highly skilled rider should be able to dial in a tune based on their experience and understanding of the HD EFI system with little to no use of a dyno.
Good luck!
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