| Author | Message | ||
     Johnboy777 |
I re-set my TPS before going to the dealer to get my new muffler (which I plan to ceramic coat, BTW) The bike has run like a champ for long time now and for some reason I got it in my head to re-set the TPS 'n AFV. I re-set the TPS and set the AFV @ 100% ... drove to for awhile at 3,200 RPM or so as to have it re-set itself, but since then it has run like chit down low. At the dealer I mentioned this to Rob the Buell guru, and he said "at our altitude they like to see 105% to 112%" When I got home I re-set the AFV to 115% and it now runs better than ever. So here's my question....why? Thanks John . | ||
| Petereid |
Just curious as to why you set it at 115% instead of in the range recommended? | ||
| Johnboy777 |
""Just curious as to why you set it at 115% instead of in the range recommended?"" ...because that's my M.O. ... if it ran worser, then I would back it down some. EDIT: I forgot to mention that my AFV was at 110% before I re-set it and my TPS. . (Message edited by johnboy777 on May 14, 2009) | ||
| Pontlee77 |
I think the range best to reset it self is between 3,5k and 4k | ||
| Okc99 |
Does that nob inside the air box do anything if you turn it? It's right under the cover and sticks up about an inch. What is that thing? | ||
| Rotorhead |
read this http://www.megamanual.com/begintuning.htm#chemistr y and this from the ECMSPY guide. Understanding the AFV The Adaptive Fuel Value is how the Buell automatically compensates for changes to the environment, eg riding up mountains, or swapping the exhaust silencer. It is not perfect, but does a good job to compensate for minor changes. When the bike is ridden in Closed Loop mode (explained next) the ECM monitors the O2 sensor and learns the appropriate AFV value to apply to the fuel maps. This AFV value is applied across the entire fuel map range, hence it is critical that this is accurate. AFV values can vary from 80 to 160% but should be kept between 90 and 110% whenever possible. The AFV can be your friend, fine tuning the bike to suit your location, or it can be your worst enemy! If you setup the bike on the dyno for maximum power across the range, you will probably aim for 13:1 – 13.5:1 Air :Fuel ratio. If you then go for a ride and enter closed loop mode, the ECM will reset the AFV to maybe 80% to reduce fuel and try to get the default 14.7% AFR. When you next accelerate hard at full throttle, your perfect map as setup on the dyno will now be running at 80% of your values hence weak! To compensate for this, it is recommended when on the dyno to disconnect the O2 sensor, reset the AFV to 100%, then tune the bike for an Air Fuel Ratio of 14.7% within the closed loop area. This will then allow you to set the Air Fuel Ratio for optimum power in the high rpm, throttle areas. Always reconnect the O2 sensor after tuning and check the AFV periodically. So what is Closed Loop? The Closed Loop area is found when riding in low throttle positions at low rpm, but not under stress. I believe this is approximately 1500-4000rpm and 10 – 30% throttle. Riding in Closed Loop allows the ECM to reset the AFV and compensate for the environment. It is good practice to do this periodically. Normal riding conditions will normally include Closed Loop riding for long enough. To ensure the AFV is about right for your setup, try and do a few miles on flat roads between 40 – 70mph and low throttle openings, with a steady throttle. This should set the AFV If you have the time, you could try riding at 2000rpm for a couple of miles and check the AFV. Next try 2500rpm and check, then 3000 and 3500. This would validate your map in this region of Throttle / RPM combination, but is a lot of effort! Remember with a narrowband O2 sensor (standard one) the readings are very slow to respond, hence the steady riding required to adjust the AFV. the cool thing is ECMSPY you can change where that closed loop area is in the map and ride outside the range you set so your AFV will stay in the 100% range. Or I think ECMSPY2 you can just turn the learn mode of the AFV off. If you do that you get a fixed map with no adjustment for ALT temps or baro pressure. Works for the track but not for the dayly commute. (Message edited by rotorhead on May 14, 2009) | ||
| Id073897 |
"at our altitude they like to see 105% to 112%" This is amazing. How far below sea level do you live, that your "altitude" requires MORE fuel? | ||
| Johnboy777 |
Say what you will ... bottom line - it works  | ||
| Florida_lime |
This is amazing. How far below sea level do you live, that your "altitude" requires MORE fuel? Stock settings are lean/hot. Richer gives better performance and runs cooler. It most likely will drop MPGs though.  | ||
| Id073897 |
Stock settings are lean/hot. Explain that to me, please. | ||
| J0hn0tt0 |
Lean = less fuel = less emissions = pass EPA testing? (Message edited by j0hn0tt0 on May 16, 2009) | ||
| Id073897 |
If the map is lean, AFV would rise until the mixture is stoich again and more fuel would be needed then, leading to more pollution. Sounds quite counterproductive to me. | ||
| Johnboy777 |
That's not fair Gunther - how can I argue with the guy that invented ECMspy. . | ||
| Armymedic |
My AFV was at 82% when I last checked. I'm at 4500 ft. elevation. Hmmm. | ||
| Johnboy777 |
Forgot to mention ... mine is usually at 110% AFV and I am at 700 ft. evaporation. . | ||
| Tootal |
The AFV is going to change to whatever condition is keeping it from achieving 14.7/1 A/F ratio. If you have a slight intake leak for instance, it will compensate for that up to a point. If you rode to a higher elevation it would change again. I have found it does take a while to change, a quick trip around the block won't do it. Setting it at 115 no doubt made it run real good because it made it richer for a while. As you ride it will change back to 110 again. |
