So my R6 came with a full aftermarket exhaust system when I bought it but everything else is stock, so no power commander. I knew it would be running lean but it really showed no symptoms of it besides a slight burble under decel and gas mileage that seemed a bit too good (45 mpg+ with conservative riding).
When I took it in to have tires put on I had them to run a diagnostic to see how lean it was running and asked them to make any adjustments if they could to hold me over until I could get a power commander which I plan on doing soon. They said they were able to tweak the stock ecu a little bit but that it was still running lean. Ever since, though, I've been getting 25 mpg or worse.
I don't really know much about how the stock ecu works or adjusting it, but it seems like if it's going through that much gas it shouldn't be running lean anymore (the mechanic even mentioned offhand that I should be getting some great mileage) . What am I missing here that would explain how it could get such awful mileage but still be too lean? Is it possible that the shop was wrong?
I guess it's also possible that something else could be wrong, but I'm almost positive there are no fuel leaks or anything. Any other possible explanations?
Like I said I'll be getting a PC as soon as I can but I'm wondering if in the meantime I should take it back and have them revert what ever they did. Thoughts?
OP - I'd think the first thing to do is take it back to the shop that did the work and tell them what the results have been. I'm guessing you/they will want to revert whatever mod they did, then see if it goes back to running as before.
How is it running now, besides the poor gas mileage?
How is it running now, besides the poor gas mileage?
It seems to be running about the same as it was, which is pretty damn well (although I dont have any other R6 experience to compare it too). Maybe a bit more responsive at some points, but its hard to say exactly.
Originally Posted by ChiefSmokeDawg
There's a way to change the fueling from the speedo unit on that bike. Google it
Basically, there isn't really a way to "adjust" the stock ECU ... the only thing to do is reflash it, which most regular shops can't do. What did they say they did to the ECU?
After looking into what chief suggested, I think they must have done what that guide describes since they had the seat off and mentioned adjusting some numbers.
I suppose I should try checking and reverting those settings back to default and go from there. I still don't understand though, how it could apparently still be running lean but get such horrible mileage.
Also, I know it's hard to say, but given that it didn't really show dramatic symptoms of running lean before they worked on it (popping or miscolored pipes, and there doesnt seem to be any audible detonation), you guys think it would be fine to ride it with the stock settings for a month or two until I can get a PC? The weather sucks so I'm not riding much any ways but I'd hate to be destroying my engine, especially since the bike only has 8k miles.
Ill check into the O2 sensor too, but what exactly happens when its not connected?
I have hacked into my 2nd gen ECU and I can say that it does make a difference when you mess with the CEL #s, but I cannot confirm what exactly it does to make that change. I went to the extremes and adjusted them 100% either direction and although it changed the way the bike ran it wasn't enough to make a huge difference. I think that the CEL #s are only for idle adjustments? I wouldn't count on it in any way to MAP the bike.
45+ mpg is good! that 6 should only be getting around 35 or so mpg. The hesitation is from a bad map for the given mods, but it won't be running too lean to be dangerous to the machine.
So after reading all the way through that massive thread I linked above I'm sure that this is what the shop did, but also really damn confused. Even thought the feature is a decade old, no one really seems to know for sure exactly what adjusting these numbers does and how best to do it. The worst part is that apparently most every bike will have its own default settings and since the shop didn't tell me what they were I guess I won't ever know (unless there's a way to "reset" the ecu or something?). If anyone here has an '04 and has messed with this I would be interested to know what your default C values are.
The shop set all of the numbers to 10 so I'm going to try setting them all to 5 and see how that affects the mileage. If that doesn't do it I guess I'll keep reducing them until I find something that works, but from what I understand after reading all that, just reducing all the numbers arbitrarily won't necessarily give me the best gas mileage.
Luke, I saw your big post in that thread and it looks like you know as much about this as just about anyone so if you have any specific advice it'd be appreciated! Were able to figure out what kind of affect different adjustments had on gas mileage?
That's just it. It doesn't seem to do anything beyond idle. The bike will change the way it runs but not to a large degree. Not enough to substantiate the numbers anyway. I have since gone back to my standard numbers ( stock ). But I also set it to the common practice of +2, +4 and even +10 as well as the same in the negative direction. As far as I can tell it doesn't really do anything worthwhile. I had been running with 0's for a while since I have a dynojet. I did that to see what I could do with the DJ unit. The only thing I have not done is test it in conjunction with cylinders one at a time with extreme differences to see if it is in fact cylinder based. I think it may be that it is cell based much like the DJ units buttons. X rpms get this amount, while x rpms get another amount above or below standard.
What I can tell you is that most people don't seem to have a large difference in numbers and that the numbers change is no proportional to their indicated percentage. I.E a change of 10 in one direction or the other is not 10%. Most stock numbers seem to be within the first 10 digits and vary from cel to cel by about as much. Mine has +5 on one as the highest but -4 on another as the lowest. The other two are -1 and +2. There doesn't seem to be any rhyme or reason. I would just set it to zero across the board and get a DJ unit. Mine had no ill effects running this way for a year. I also run a zero map on my DJ and only use it's cylinder trim function to lean or enrichen the motor. The mods I have done are carefully picked and work rather well with stock mapping.