Fuel Cut Eliminators, ECU reflash for FI issues/Throttle Snatch

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Also thought that one could find a spare used ECU if one was interested in preserving one original. More cost. ECUnleashed order form also pointed out that us Canadians and Europeans have an ignition immobilizer, meaning I can't just go find a standard US ECU.........
If you use a USA ECU, you would no longer have immobilizer. Then you could use any key blank you wanted ;)

 
However, the lean fueling of the Gen2 cannot be "fixed" mechanically. There has to be electronics upgrades/changes for that. It was worse on the '06 and '07 but was still present for all of the Gen2 bikes.
I am not convinced it was present on all the Gen II bikes. My 09 is smooth as butter. (stock) Others have ridden it and agree. Though I do know that not all FJRs are created equal; even in the same model year. There are variances.
There has to be. You rode my bike and didn't have any complaints. Supposedly, my '07 is the worst of them. My throttle was never stiff and never needed unwound. I don't have a Power Commander, and haven't done anything to it except ensure my throttle cables are adjusted correctly. Learning how to ride a properly adjusted bike would save people thousands...Unless this "problem" really is as severe and prevalent as claimed and I just got lucky.
Dayum...I must be good... Never had any altitude sickness problems. Never any Spider problems. Never any ignition switch problems. Maybe my bike wasn't built on a Friday.

 
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Hmmm-wonder if this would fix the dreaded "lurch"

https://www.sol2.be/Performance/ENG/BMW/index_YAM.html
Bad science engineering redneck engineering. They couldn't even get the sppelling corrects on there web site. All their air temperature sensor does is lie to the ECU to create a rich condition. Excessive richness causes the engine to slightly bog which takes the edge off of engine performance and crispness which we perceive as improved smoothness.

 
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Alan beat me to it. I was going to say almost the same thing. But the real kicker is that the "Accelerator" would not even address the root cause of the "dreaded Fuel Injection lurch," which is the total fuel cut on trailing throttle that is incorporated into every Fuel Injected motorcycle ECU.

The only way that I know of to beat the Fuel Cut is to spoof the ECU into thinking that the throttle is never fully closed. What that threshold is may vary by bike, and I don't know what it is on the FJR, but it would be easy enough to do by advancing the TPS by xx%. Of course that would then require re-programming the entire fuel map since the bike would be running way too rich across the board. It might be possible to do that by subtracting fuel using a PCIII.

Might have to give this a try sometime when it is a bit warmer out.

 
Yeah, their spelling and sentence structure makes one wonder- but they are English...

On their "how's it woik page" they claim that the only time the accelerator affects the ECU is under acceleration [hence the name?] . Not sure how that would get around the fuel cut unless the fuel cut is only in effect at higher temps, but that would have to be engine temp and not ambient air temp.

In any case the boys at MCN loved it on a BMW, even claiming a 10% fuel economy boost and a negligible horsepower boost.. They did test two different brands of the same type of device..

 
Maybe there is some confusion in the way the phrase 'fuel cut off' is being used. Yamaha is very up front in the Technical Guide and the FSMs about there being a deceleration fuel cut off when the throttle is closed. Here in the Forum we talk about the FJR meeting EPA emission specs yet motorcycles are not emission tested after OEM certification. There are features from OBD II that show up in the FJR's software in addition to the hardware like the cat-con and O2 sensor. One software function is Deceleration Fuel Cut Off (DFCO).

(Description of DFCO in OBD II)

Most modern gas vehicles cut off the fuel supply completely when coasting (over-running) in gear. When coasting with the engine running and manual transmission in neutral, or clutch depressed, there will still be some fuel consumption due to the engine needing to maintain idle engine speed. While coasting with the engine running and the transmission in gear, most cars' engine control unit with fuel injection will cut off fuel supply, and the engine will continue running, being driven by the wheels. Compared to coasting in neutral, this has an increased drag, but has the added safety benefit of being able to react in any sudden change in a potential dangerous traffic situation, and being in the right gear when acceleration is required.[citation needed]

It should be noted that Coasting with a vehicle not in gear is prohibited by law in most US states.


DFCO has been an OBD requirement for all vehicles for >15 years. It started showing up in a few car models in the late '70s.

The car guys I hang with are a lot like the Forum guys and we ISSCONE guys purchased a programmer and started rolling our own tune-ups and making other changes. Anyhoo, the mid 90's Impala SS factory set DFCO was on a timer that delayed cut off for 2.5 seconds so you could lift your foot and not get immediate DFCO. It seems that the FJR has no delay, as soon as the throttle is closed DFCO is initiated which is what makes it so rude abrupt. If there was some deceleration before DFCO was initiated it would make it a bit smoother. When OBD II DFCO was being implemented no consideration was made for very light, extremely high output motorcycle engines.

 
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My big peeve is the DFCO and I hope to learn more as I get into it with the ECU guys and the FCE guys (been too busy to dedicate the effort it's gonna take, but soon).... what I'm gathering so far is the FCO is also related to certain rpms, i.e., anything below say 4500 rpm on a sport bike with throttle closed. Probably much less on a sport touring bike, but ideally, rpm would be out of the picture, or the lowest possible rpm would be good. I think I mentioned this before, but I have seen a fuel map for a PC that fed in richness at something like 2200 rpm at throttle position zero (other maps don't put anything in at zero position), so I'm going to try that too. That's just masking the problem, but if it works, it works.

I have read about adjusting the TPS, and we'll have to look into that.... Testing of course will start in the spring...... it's going to take a while to iron all this out.

 
the accelerator does not of course eliminate the fuel cut but neither does the PClll or V and folks rave about how much they improve throttle response. All these devices seek to improve fueling by making the mix richer. If the FC doesn't happen under a certain rpm or ambient temp, that should help..I have done the BJM and raised the CO2 settings nine points which should richen idle mix and did produce a noticeable improvement.

for 50 bucks I might try the snake oil accelerator...I can't imagine that it would produce an overly rich condition that would stifle engine performance, especially on a mill that is already running on the lean side. Larger pilots and mains in my FJ1200 blackened the plugs but added 1/2 second in the 1/4 mile to @10.2.

 
I have seen a fuel map for a PC that fed in richness at something like 2200 rpm at throttle position zero (other maps don't put anything in at zero position), so I'm going to try that too. That's just masking the problem, but if it works, it works.
BTDT, it doesn't work. All it does is create a too rich condition when running in those rpm/throttle conditions any time the fuel cut is not active. When the fuel is cut it is still zero fueling regardless of how much you "add".

The conditions for fuel cut would have to be engine rpm above XX, AND throttle position of zero +/- Y %. Any times those two conditions are true you would be decelerating on trailing throttle.

the accelerator does not of course eliminate the fuel cut but neither does the PClll or V and folks rave about how much they improve throttle response. All these devices seek to improve fueling by making the mix richer.
This is true. I happen to be one of the people who call BS. Yes enriching the lowest throttle opening conditions makes the off to on throttle lurch feel softer. It does that by making the mixture overly rich so that, once the cut is lifted, the power produced initially is less pronounced. But, that is pretty non-elegant way to fix the problem, and compared to a constant fueling of a carb that lurch is still there. Most people just get used to it and learn to "ride around it."

 
Agree with you, Fred. Those are attempted fixes by trying to fool the system. The true fix is to program the fuel cut right out of the ECM. Brings us back to the rather expensive ECU reflash..... which for the moment, I'll assume works. My responses so far with ECUnleashed, are mostly hype about more horsepower, new fuel map, blah, blah. I don't care about most of that, but would like a nice simple fix that doesn't cost $500. Still working on them to put aside the hype and talk more realistic.

The FCE by Ivan's is another workaround thing that tries to fool the ECU....... there are mixed reviews from ST owners on that. Not ideal.

Another big question, how are you guys with '13/'14's finding the fuel cut.... need some ride reports.... so far the tidbits indicate smoother response from the throttle by wire, I totally see it, but do they still have a wee bit of fuel cut? I'm itching for a Gen III for that reason if it's fixed....... albeit a bit more than a $500 upgrade.... did I mention I love that red.......

 
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I have used AutoTap to view and flash GM PCMs. The way OBD II is set up you can't eliminate most OBD II functions, all you can do is alter the values and ranges that it uses. In the FJR application what you can do (assuming OBD II type compliance) is to set a delay timer. When the throttle is closed you can increase the time delay before FCO from almost instant which produces the abrupt feel to something like 3.5 to 5 seconds, this lets normal compression braking start before FCO which will vastly improves feel. There is a range that the delay can occur in, the delay can't be made infinite.

The other value that needs to be changed is the delay from reopening the throttle until FI resumes. Right now there is enough delay that we over-open the throttle before FI resumes which causes abrupt throttle feel. Be reducing the delay you get the feel of the throttle moving in sync with fuel injection.

Times have probably changed, but when Scott and I were flashing PCMs we had to use two external power supplies to ensure no programming errors.

If the Gen III has an OBD II connector we can use AutoXray or equivalent to look at everything that the ECU is seeing which makes troubleshooting and operation evaluation much easier.

 
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Put a PCV with Autotune on mine and it fuels with no hitch coming off closed throttle or light throttle. It came with the standard Fuelmoto map and then I went in and adjusted the air/fuel ratio on a couple of areas that looked lean. Gained smoothness, a slight power jump and slightly better mpg if I'm conservative. Also smoothed out the cable ramp on my stock throttle tube to emulate what a G2 tube does, and removed any slack, couldn't be happier with the FI now. This was over three years ago, still runs without a hiccup.

 
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Well the ECU Unleashed people i have dealt with on my FZ1. They specify the same criteria of fixes for the FZ1 as they do the FJR and all bikes. Myself and quite a few others on the FZ1 forum had many issues with their flash and I had many many many bad results which resulted in a lot of down time and tearing apart the bike mulitple times which on that machine is not easy. They had an excuse for everytime there was something screwed up or wrong, saying there are too many ECU's for the FZ1, too many diff stock configurations, didn't have one to test and so on and so forth....the Fuel cut on the bike was nasty and after putting ivan FCE it was much better, after the flash the fuel cut was damn dangerous with or without the FCE. Also the inability to contact these people or have them get back to me in a timely manner also sucked. The long and short of it , is that they could not on my bike and others back up their claims, with diff year bikes that they said they tested, after much fighting they refunded my money and flash the ECU back to stock.

Ivan saw all of this and actually called me to discuss what they had done, he was not impressed with the way they went about their claims or how they handled it....which led him to start doing it himself and take on that new way of adjusting for mods.

Why couldn't all manufactures be like Suzuki and let you reflash the ECU easily..?

 
Thanks, mavrik. I was a little concerned about their email to me, lots of hype, but when you get asking specific questions it's evident they maybe dont want to be specific. So, I think I'm just going to write this idea off, as most of the folks here aren't gonna spend the $500 anyway (IMHO).

As for Ivan's FCE, that device is trying to fool the ECU..... ST guys had mixed reviews, sometimes having to stop and "reboot" to get it working properly again. We'll see.

Perhaps I should just do more experimenting with the PCV and perhaps add an autotune...... got the G2. After that, down the road a Gen III.

 
Dayum...I must be good... Never had any altitude sickness problems. Never any Spider problems. Never any ignition switch problems. Maybe my bike wasn't built on a Friday.
A LOT of this depends on which bike you have and how you ride. Most folks...entering corner. Get on the brakes, pull in the clutch and close the throttle. Fuel Cut kicks in and shuts down the injectors. As you enter the turn, it's time to make sure you are in the right gear so you shift, roll on the gas...FI kicks back in and your rpm's increase and as you continue to roll on you let out the clutch.

In this case...butter smooth. Why? You never noticed because your clutch wasn't engaged when the fuel cut was doing it's thing. Do the same thing but don't ever pull in the clutch. Brakes, shut down throttle, lean into the turn and roll back on that gas. You'll likely feel it then.

Why on earth would someone ride like that? Well, those of us retards with the AE model...that's how it works. Unless the bike is stopped or shifting, the clutch is always engaged. So when we get on the brakes and shut down the throttle, the clutch is still engaged, tip it in and roll on the gas...lurch.

As stock, the bike has more issues than just the fuel cut, which are easily fixed with the throttle cam via something like the G2, as well as a Power Commander. You still cannot get that fuel cut though without another device. My AE bike is butter smooth with those mods except that fuel cut area.

Ivan has had success with the FZ1 on his FCE, no complaints like mentioned on the ST forum. No idea why he never looked at our bikes because clearly our owners don't have problems spending money on them.

That said, if the price was right (not $500) I'd be one of the first in line for a bona fide fix for this. Of course, it would also depend on who's selling it, because certain folks will never get a penny from me. I'll sell my bike first if it's that bad.

 
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Dayum...I must be good... Never had any altitude sickness problems. Never any Spider problems. Never any ignition switch problems. Maybe my bike wasn't built on a Friday.
Most folks...entering corner. Get on the brakes, pull in the clutch and close the throttle. Fuel Cut kicks in and shuts down the injectors. As you enter the turn, it's time to make sure you are in the right gear so you shift, roll on the gas...FI kicks back in and your rpm's increase and as you continue to roll on you let out the clutch.

I have never heard anyone advocate pulling in the clutch and coasting while braking when entering a corner before. That sounds like a great way to ensure that your power delivery is herky jerky.

Nobody is doing that.

 
Hrm...maybe where you ride helps too. Fred W lives in NE with endless curves. Here it's a couple mile 120mph straights along the edge of farmer bobs pasture, then a 20mph curve around the corner, then another straight section.
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Hrm...maybe where you ride helps too. Fred W lives in NE with endless curves. Here it's a couple mile 120mph straights along the edge of farmer bobs pasture, then a 20mph curve around the corner, then another straight section.
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You should be all done shifting/breaking BEFORE you get into the corner... and back on the gas when leaning over to make the turn...
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