Richer fuel map for a standard XB

[John Vreede]

I’m looking for a richer fuel map for my bog standard ’07 Uly, as if the factory tuned it for best running without regard to emissions.
With the standard map it misfires occasionally at small throttle openings, like when I'm idling along in slow traffic. It also gives a sense of not running properly everywhere else, a sort of edginess to the throttle response, which I believe is because the factory programmed it lean to meet emission standards.
The misfire and that 'lean running' feeling disappears when I lock the upper and lower AFV limits at 108%. Now it has a liquid surge of power from 2500 - 4000 rpm and throttle response that's great, although the engine braking is worse.
However, I understand locking the AFV like that gives 8% more fuel everywhere, even where it’s not needed (like engine braking) and maybe not enough in other places. I also loose altitude compensation and closed loop running fuel efficiency.
What I'm looking for is a map where the bike runs as well as the ~8% enrichment at normal road speed (50-70mph) while retaining the altitude compensation and closed loop running and decent engine braking.
I thought I’d found the answer with the IDS ‘Performance ECM for the Stock Bike’. However, Tim at IDS says it’s essentially the same map as the 07 XB and that I wouldn’t notice any difference with it, and that I should continue to run with the AFV locked rich.
Does anyone have an optimized map for a stock bike I can load with EcmDroid? If not where should I go from here?
Thx - jv

 

[Cooter]

You can run the stock map richer (must leave it in open loop) and adjust for altitude by adding a Barometer (baro sensor). The stock ECM has the capability.

I have had good luck as much as 115AFV on a bone stock bike.
https://www.buelltooth.com/baroxb.html

 

[John Vreede]

Thanks Cooter, but its not quite what I was after. Buelltooth say it's Baro kit only works on 03-07's if you are not running the Active Muffler Control and have an aftermarket muffler & ECM tune: I have a stock exhaust and want to run the AMC.
I'm hoping that someone out there has optimised the fueling on a standard bike. I can't be the only one who wants this??
It seems ECMSpy can do it- if you know what you're doing. I'm new to this and don't feel up to that yet.
Rgds - jv

 

[gunter]

For a stock bike, no AFV changes are needed. Buells do not run lean on a stock map, because CL and OLL will help to avoid this.

 

[njloco]

Cooter, I thought the Buelltooth baro sensor won't work on 07 and earlier Buell ? Did you have to do anything special ?

My mistake, it won't work if the exhaust valve is still active, like on my bike with the spec ops muffler.

 

[John Vreede]

Gunter, I believe something has been lost in translation.
By '...running lean...' I did not mean the the standard fuel map in the Buell was making it run at an AFR >14.7, but that is was running leaner than would give most enjoyable riding, which most people say is about 13.6:1.
My bike ran with the AFV at 102.3% when the standard upper and lower AFV limits were operating. I gather this means the bike is performing as Buell factory intended.
When I disabled the closed loop running by applying an upper an upper and lower AFV limit of 108% the bike was vastly more enjoyable to ride.
I'm looking for a fuel map that will give this sense of enjoyment when riding in open loop mode but still run in closed loop when cruising, give barometric compensation and run the std AMC
Danke - jv

 

[gunter]

When I disabled the closed loop running by applying an upper an upper and lower AFV limit of 108% the bike was vastly more enjoyable to ride.

Limiting AFV has nothing to do with closed loop operations.
With a default WOT correction of 110 Buells run at about AFR 13.3:1 at WOT.

 

[Cooter]

Hey Gunter: Sorry for the side track, but just confirming the AFV is a ECM "global map adjustment", but for OL only?

Where EGO (WEGO) is for CL only?

 

[ReadyXB]

...
With the standard map it misfires occasionally at small throttle openings, like when I'm idling along in slow traffic. It also gives a sense of not running properly everywhere else, a sort of edginess to the throttle response, which I believe is because the factory programmed it lean to meet emission standards.

A stock bike with a stock map should not run like this. Best to try and sort out what the cause may be before tuning it, or else you may end up more frustrated chasing a moving target.

 

[John Vreede]

I guess you may be lucky Ready. to have a bike that doesn't do this.
The evidence from lots of other owners on this site is that they do have 'lean stumbles' or 'lean misfires', even in stock tune, and there is a whole industry built up around providing stock bikes with a way to get their fuel injection system to run richer (https://www.boosterplug.com/shop/frontpage.html, http://nightrider.com/).
Jens Lyck, of Boosterplug above,has written a booklet on motorcycle fuel injection that's an interesting read,explaining the various ways to do it. https://boosterplug.com/images/shopdownloadfiles/BoosterPlug Fuel Injection Book.pdf
I'm pretty sure that my bike is running as Buell intended, the AFV of 102% shows the ECM is not getting any signals to make it much richer or leaner than the std fuel map.
But it's a fact if I force it to be richer everywhere in OL by setting the AFV limits to 108%, the bike is waaay nicer to ride. That's why I'm after an optimized map.
I've still got to come to grips with what Gunter is saying re locking the AFV not affecting CL though...
Rgds - jv

 

[Cooter]

But ReadyXB is right. A stock bike in good shape shouldn't misfire.

The old wives tale of a vehicle meant to run 'lean' for the EPA has always been hogwash. An engine running even slightly lean will have terribly high NOx and Hydrocarbon (HC) emissions, both of which are scrutinized by the emissions police. MFG's don't shoot for lean, they shoot for stoic (14.7:1 in CL). 14.7:1 is not lean, it is efficient and clean burning. An engine running even slightly rich in CL will have higher Carbon Monoxide (CO, also scrutinized) but will have better throttle response because when the engine needs the extra gas, *it's already there immediately without waiting for the ECM/injectors to compensate.

You will never see more power in closed loop because, by definition, closed loop is part throttle, cruise condition. Keep your AFR targets in CL at 14.7.

AFR targets in OL are a different story. MFG's are not able to dump mass amounts of fuel into the engine (causing high CO) for acceleration because of the EPA. There LOTS of opinions on what targets to use, but around 13:1 is typically accepted for V-twin performance.

*this may be why you think it runs better with the AFV locked at 108%. The rich cylinder has extra (normally wasted out the tail pipe when cruising) fuel ready to be burned when you blip the throttle.

I'd still check the intake seals though.

 

[gunter]

Hey Gunter: Sorry for the side track, but just confirming the AFV is a ECM "global map adjustment", but for OL only?

Where EGO (WEGO) is for CL only?

AFV is applied in open loop operation only, whereas EGO correction is applied in closed loop only.
AFV is also the reason, snake oil like the mentioned devices will not work. Fuel is added because of a fake temperature signal, EGO corr. removes fuel in CL to get a stoich mixture, AFV is dropping because of EGO, fuel is removed in OL, and you are where you were before. This is also the case for each ECU manufactured the last 15, maybe even 20, years. Better donate for a copy of EcmSpy, because this is known to work.

Stumble at very low engine speeds seems almost always a timing problem, and take into account that all "Idle ..." settings get active once engine speed is below the Idle Max. Engine Speed.

 

[Cooter]

Thanks Gunter for the clarification, and nice to hear from you. It's what I thought, but in searching the ECMSpy instructions I couldn't find it spelled out precisely that way.

Another question if you don't mind: What are your personal favorite AFR targets for WOT on a XB? Are they the same for 9 vs. 12? Mods? I feel if I get good enough at tuning Stella, when it's time for a 1250 kit I could start with it's current tune and datalog with the same WB O2 I have to make a good 1250 tune for her.


Sorry OP for the hi-jack and whole-heartedly agree about the sensor mod trick devices.

 

[gunter]

I never tuned the WOT part of a map using a WB O2 sensor, as I do not have access to an EC dyno, and anything else would be a waste of time, budget and fuel.

 

[Cooter]

I have a great dyno guy close by, but that adds up $$:upset: so I'll WB, OL tune on a 3 mile arrow straight road (with only one entrance ramp) near me:angel: to get close, then finalize quickly with about an hour of dyno time when I finally get the chance.
I'm only tuning for good safe mixture (not HP), so it works for me.
At 13:0 OL targets, theres no black smoke, I haven't had an issue fouling anything, and can't seem to get any more power when I'm actually on a dyno. Thought you might have a different experience.

Thanks again, your wisdom is appreciated

 

[John Vreede]

Sorry OP for the hi-jack and whole-heartedly agree about the sensor mod trick devices.

No problem Cooter - when you heavyweights talk, we all learn. I wasn't endorsing the sensor mod trick devices, just illustrating that there are a lot of people who find the emission regulation compliant fuel maps unsatisfactory, as do I, if it runs nicer when richer. Even you said you'd had good results locking the AFV up to 115%.
I've a question for Gunter re his comment about "Limiting AFV has nothing to do with closed loop operations" and the ECMspy tuning doc '5.1.3.2 Closed Loop Learn...The fuel (in CLL) is metered the same as in the Closed Loop region, except after 23 iterations of a difference between EGO and AFV, the AFV is reset to equal the EGO correction.'
Until now I understood that when locking the AFV the closed loop function (of reducing AFR to stoich at cruise) was also effectively disabled. Is that not true? Does the fuelling in the closed loop area still respond to the EGO sensor and come back to stoich, while just being unable to alter the AFV after the 23 iterations?

 

[Chicknstripn]

Only contribution I’ll make to this thread is that you first insure that everything is mechanically sound with the bike before you start messing with the fuel maps. Check all your grounds, do the dedicated battery to coil ground, check your plug wires, check your plugs, insure you don’t have an intake leak, make sure your TPS is set correctly... and I’m sure there are other checks that I’m missing that will be mentioned. The point is, if you don’t make sure the bike is in perfect mechanical order, changing the fuel maps will only compound any running issues.

 

[gunter]

Until now I understood that when locking the AFV the closed loop function (of reducing AFR to stoich at cruise) was also effectively disabled.

This is not the case. AFV is always limited, and always checked against its threshold values.

 

[John Vreede]

Thanks Gunter.
So does this also mean that, even when both upper and lower AFV limits are the same, that the ECM will still drive the fueling in the closed loop area toward stoichiometric - jv

 

[John Vreede]

An update after naff winter weather cleared.
1. Fuel mileage is the same (51mpg) with the AFV locked at 108% as when I was running with the standard settings (which allow the AFV to find its own level), so I guess that answers my question above - the ECM did drive the fueling in closed loop back to stoichiometric. Since the AFV was 102% when the factory limits were in place, I guess the gas mileage would have been 6% lower if the CL wasn't operating.
2. Did the PCV hose reroute and seemed to make a slight but noticeable improvement in driveability, so I cut the AFV locked values back to 107% (I'm working on the assumption that closer it is to 100% the better).
3. Tried 'Deceleration Fuel Cut' (in ECM Parameters;General Config; System in EcmDroid) to see if it improved engine braking. It did, but made on/off throttle transition too jerky, so I disabled it again.
4. Found an old post (that I can't get back to now) that said someone (I think one of the guru tuners at the time, or was it the inventors of EcmSpy or EcmDroid?) had found that the factory midpoint voltage for the O2 sensor of 0.49V equated to 14.9:1 AFR, and that the bike was more tractable and had better cold weather performance when the value was raised to 0.50V which put it closer to 14.7:1 (and some bikes responded well to 0.51V or 0.52V). Since it was a no-lose situation I decided to try it. It made an immediate and very positive difference! The bike idled more evenly, was smoother everywhere esp on/off the throttle and pulled from lower revs than its ever done. Pulls cleanly from 20mph (30kph) in 2nd and even from 12mph (20kph) with a little bit of drive-line snatch. Subjectively as much of an improvement as locking the AFV at 108% made originally. So much so that I'm thinking of putting the AFV limits back to std and seeing if it is acceptable, then maybe trying 0.51V. Didn't think such a small change could make such a difference. If like me you like improved driveabilty - try it. Easy to restore to old setting if you don't. In EcmSpy its under the ECMconfig tab and in EcmDroid its under ECM Parameters; O2 setup;O2 Sensor. - jv