| Author | Message | ||
     Xb9 |
Went to the track yesterday to instruct at the Nelson Ledges Track School. Got about 200 track miles on her for the first time, got a chance to stretch her legs some. Actually, I wailed on her pretty good  Anyway, after that exercise, the front value came up some. We'll see if it goes back down after I get some more street miles on. oh, and after that abuse it felt like it gained about 10 horses, does nice third gear power wheelies off turn 13 now. This bike is sooooo bad azz. It's fun doing power slides off of turn one at over 100 MPH. New values: Box stock 1275 miles Cleveland, Ohio 1150 ft. ASL F LFV: 94.5 R LFV: 100 (Message edited by xb9 on April 27, 2008) | ||
| Zac4mac |
This may well be an exercise in futility - From the Electrical Diagnostic Manual: "The adaptive fuel value, learned during closed loop operation, is applied to open loop operation to adjust fuel and spark maps for optimal performance." So it appears the Adaptive Fuel Value adjusts while riding, so you can start without touching the throttle and has no effect once the bike is warmed up to operating temp. My interpretation from the manual, I could be way off. That's all I could find except for a blurb that AFV is in "percent". Z | ||
| Blake |
AFV applies to the entire fuel map. Basically it is adjusting for changes in ambient conditions but based upon O2 sensor readings during steady state cruising type operation. | ||
| Xb9 |
Blake, May I add that is correct for DDFI II. Do we know for sure if DDFI III works the same? Buell did change the terminology from LFV (Learned Fuel value) to 'Adaptive Fuel Value'. ???????????????? Lot's of questions, no one's talking and there's no documentation, so I guess we are left speculating. | ||
| Bigblock |
F 99.5 R 100 3,084 miles. Sea level. | ||
| Blake |
I've only ever heard it referred to as AFV, until now. | ||
| Al_lighton |
From what I've been told by folks that should know, the AFV on the 1125R DDFI3 is very similar to the AFV in DDFI2, except for that it is independent front and rear, and that it doesn't need to move as far because it isn't being asked to compensate for air density like in the XBs since it has that data mapped/scaled from the MAP sensor. But it's basic function hasn't changed. Note: I think DDFI3 is the term applied to BOTH the 1125R and the 08 XB's. | ||
| Xb9 |
Man, after riding this thing a bit after thrashing her at the track, I've noticed that: 1. The engine runs noticeably smoother with less vibration. 2. More power. I think she likes it rough..... | ||
| Slypiranna |
I would like to understand the LFV's learning curve more. Am I correct in believing that the ecu ONLY adjusts in closed loop operation and then applies this increase and or decrease percent to the open loop map? If the above is true...then how can the LFV's adjust at all (or incredibly slow/many miles) if the bike is recommended by all dealerships & BMC customer service (that I've contacted) and only run above the 4k rpm regions? The actual transient time event from idle to upshift cruise to 4k rpm would be less than a minor snapshot from a feedback/accurate learned by history standpoint. Does anyone have the ness'y information that fully lists the LFV's needed parameters...and or factual data? This will help in diagnosing cures for those of us that have minor issues in closed loop operation...cruising below 4k rpm in urban street applications. IE...true street bike applications. PM if ness'y... | ||
| Cutty72 |
I don't know, mine had adjusted before the reflash. 95 f and 92 r. Since getting reset to 100 on both with the reflash, they have not adjusted at all. Over 700 miles and all sorts of RPM changes. | ||
| Slypiranna |
Correction...Adaptive Fuel... | ||
| Thurstonbuell |
Mine have not adjusted either , both have stayed at 100% , dont remember exactly , but they were also about 95F and 90R , and I have over 600 miles of all sorts of driving , and ALOT of driving restricted to below 3500 rpm (since the re-flash)whats that mean ???? I have no clue...  (Message edited by Thurstonbuell on May 19, 2008) | ||
| Zac4mac |
Perhaps the reflash shifted the numbers in the ECM for calculating AFV. Prior to reflash mine was at 94.5 F&R. After reflash, AFV reset to 100 F&R and ran decidedly rough at less than 4k and a little bumpy above 4k. Not a happy motor, certainly less smooth than before. Around 600 miles post-reflash, AFV changed, but the wrong direction. Now it's at 100 F & 105 R and even rougher. I baffled and frustrated, Loretta's not fun to ride right now. Z | ||
| Thurstonbuell |
ZAC , I feel your pain brother , mine did the 105 & 100 thing , was real bad , now that she settled in at 100 F&R , not as bad , but no pleasure to ride thats for sure . | ||
| Ccryder |
With all this talk of AFV, I guess I'll have to go check mine at lunch. | ||
| Xb9 |
Sly, my understanding of DDFI II: "Am I correct in believing that the ecu ONLY adjusts in closed loop operation and then applies this increase and or decrease percent to the open loop map? " the ecu ONLY LEARNS in closed loop operation and then applies this increase and or decrease percent to the map It will affect both open and to a degree, closed loop operation. That is why you must have the AFV at 100 with the O2 sensor disconnected to do any adjustments to the fuel maps. And if you're tuning in the RPM/TPS region where it learns (unknown on the 1125), it must be dialed in to 14.7:1 The AFV does not change any map values, it is a factor that is applied to any cell in the map. So if the cell you are operating in is 150, and the AFV is at 95 you will get a 142.5 milisecond duration on the injector. There may be other correction factors as well. Now the MAP sensor on the 1125 may further adjust things up or down either independent of the AFV or in combination with. ?? | ||
| Spectrum |
So I made an interesting observation today. I did a track day at VIR and thrashed the piss out of the bike. Kept the revs high and even bounced of the limiter a number of times. She is now running smoother than ever with only a very slight surge when holding a steady 3500K. What's interesting is I've ridden over 800 miles since the reflash and it was setting at 90/100 since I rode it home form the dealer. I did all kinds of steady low RPM's (below 4200) and the rear sensor never learned. But one day thrashing her on the track and suddenly she learns. Some one else said it firts, "she likes it rough!" New readings Elevation 510ft F - 90 R - 90 miles 4100 | ||
| Slypiranna |
Well, that is two now that have said the same thing...guess I know what I'll be trying next... Thanks for the input guys...keep it coming. | ||
| Xb9 |
ok, got my bike back after the reflash. It does seem to run smoother,better in some respects, except when cruising in the 3-4K range - that is now worse!  And that's the only area I had a gripe with in the original calibration. You'd think that's where the improvements would be focused. Left the shop the AFV's were at 100, stopped after I got off the freeway and they had not adjusted. Rode about 15 more miles on the secondary streets while it was bucking and surging in the 3-4K range. Seemed to get worse the more I rode it in this range Checked it again when I got home and the Frt. AFV went to 95. Rear is still 100. I just don't get it. Something in the ECM programming is way screwed up. The bike is obviously running lean in that range, and when the ECM learns, it makes it even leaner . Doesn't make sense. Someone at Buell needs to get their S$&t together and get it sorted out, and quick. If they have to run it that fricking lean to pass the emissions, then they should have put a damn cat on it to begin with. This crap I never noticed on the track before I bought one, but I thought it's supposed to be a street bike first... sorry, had to vent...very frustrated. Update: please read my post 5/22/08 in the 2008 Buell 1125R ECM Update/Reflash thread (Message edited by xb9 on May 22, 2008) | ||
| Spatten1 |
I don't think DDFI 2 has any way to adjust for altitude unless you tool around in closed loop and it sees it is too rich or too lean. In other words, with no MAP or baro sensor, it has no way to know altitude is changing unless you ride in closed loop and it sees things have gone rich or lean across the board. Problem is BUELL WILL NOT TELL US A DAMN THING ABOUT THE SYSTEM SO IT IS ALL GUESSES. | ||
| Slypiranna |
"I don't think DDFI 2 has any way to adjust for altitude unless you tool around in closed loop and it sees it is too rich or too lean. In other words, with no MAP or baro sensor, it has no way to know altitude is changing unless you ride in closed loop and it sees things have gone rich or lean across the board. Problem is BUELL WILL NOT TELL US A DAMN THING ABOUT THE SYSTEM SO IT IS ALL GUESSES." I believe the poster was using the ddfi2 as an example...as we all know the 1125 has a map sensor. I don't think anyone here is guessing at anything. We are LEARNING. We are collecting information and collectively trying to understand the way this system operates with a wide source of what seems good input and a previous track record of earlier systems fuctions...as I doubt BMC engineers threw the earlier one out the window entirely on this updated version. It would only make sense to IMPROVE on the ddfi 2 if only from a cost standpoint in development. This efi system is by no means impossible to figure out, given time. I already know of one out there testing an aftermarket tuner as early as a month ago...still not ready for the public but they have at least understood this system. Improvements come in small steps but I feel that we can improve further upon this platform... If I looked at my work everyday with the attitude that there is no manual and there is no one there explaining every single detail...well then I'd be out of a job! Thankfully, I don't and I'm not. Next please | ||
| Ccryder |
Checked my values Frt=94 Rear=100. Besides a little (much less than before flash) surging in the 2500-4000 rpm range, SHE ROCKS! Next. | ||
| Jknox91 |
sorry for being a newb... but what do these values account for 100f 105 r, and how do they affect driveability as they change? Furthermore where do you get these numbers? from hooking to the ecm with a tool or sdimply through an interface on the cluster? (Message edited by jknox91 on May 20, 2008) | ||
| Zac4mac |
The display will have that and a lot more info, when you put it in Diagnostic Mode. Access DM by pressing the MODE and TOGGLE while turning on the key. in RUN, you have lo-beams on, which is good for battery "load testing". In the fork-locked PARK position,the system turns on less circuits and you have close to a "no load" battery condition. You can start while in RUN based DM, but the display goes away as soon as you start rolling. Very useful feature, well worth the price difference from an XB12R. The Adapt Fuel Values ROUGHLY coincide with altitude. 100 is supposed to be sea level, lower numbers for higher elevation, Death Valley should be around 105-110. Other factors are at play though, so it's not a straight link. edit - The AFV is derived from the O2 sensor readings, it is a percent multiplier for fuel map cell calculations. An AFV of 100 is a "times one" on the cell. Z (Message edited by zac4mac on May 20, 2008) | ||
| Rdmwc |
i just checked mine, and my front is 95 and rear is 105. im not sure what my elevation is, but im in wisconsin | ||
| Slypiranna |
Thanks to Xb9 ...originally posted this link to find your elevation, http://www.wunderground.com/ check it out and let us know to keep it going! next please | ||
| Rdmwc |
970ft. thanx for the link. | ||
| Jknox91 |
new enlightenment, thnx Zac! | ||
| Cutty72 |
Mine finally changed after the reflash. A lot of "spirited" riding helped that. 100 rear, 94.5 front. runs much smoother down low now. | ||
| Rdmwc |
so its safe to say that mine has the largest gap between the front and rear? is this good or bad? now im gettn worried |
