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Yeah, I started reading that thread, but seeing as it is about a different engine, with a different EMS, I really couldn't be arsed. With all the folks on here sporting decat headers I hoped someone would have a dyno plot with AFRs.
But hey, you seem convinced the EMS adapts to an IAT spoofer, so would it not adapt to a less restrictive exhaust?
Too bad you didn't read farther. Then you'd know the answer to your question is yes. And for the same reason the booster plugs' effect is negated. If your new exhaust does lean the mixture (the ECU can only "see" this at part throttle where the narrow band O2 sensors work and the ECU maintains a 14.7 mix so the convertor works) the ECU will adjust (trim) to get back to 14.7 and then apply the correction outside of that area. It won't optimize, it can only add or subtract across the board.

The Motronic used the same basic logic. They have since they got O2 sensors. The BMS-KP and the BMS-MP are just more powerful and more sophisticated and the BMS-MP has a lot more checks to keep people from fooling it.

Too bad you "really couldn't be arsed". You might have learned something.
 

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Too bad you couldn't link to specific data (i.e. not a 107 page thread!) in a helpful manner instead of just being a condescending know-it-all.
Auf wiedersehn pet.
Plonk!
 

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I'm at work right now so I can't get access to the GS911. Is there an menu option to RESET the long and short term trim levels? Granted I haven't plug the GS911 tool for over 6 months now. So my memory is kinda hazy.
 

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Is there an menu option to RESET the long and short term trim levels? Granted I haven't plug the GS911 tool for over 6 months now. So my memory is kinda hazy.
Yes there is. Haven't used mine for quite a while also so I can claim hazy memory too but it's there.
 

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Yes there is. Haven't used mine for quite a while also so I can claim hazy memory too but it's there.
There you go, I resetted the trim values back to factory 0%. It was at -3.2% and -2.6% for short and long term trim values.
This is the first time I did this procedure. I keep a metal note next time I go for a ride.

I notice GS911 says the inlet temperature is 21DegC when in actual fact the garage temp air temp is 32DegC. So the boosterplug is doing its job.
 

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There you go, I resetted the trim values back to factory 0%. It was at -3.2% and -2.6% for short and long term trim values.
This is the first time I did this procedure. I keep a metal note next time I go for a ride.

I notice GS911 says the inlet temperature is 21DegC when in actual fact the garage temp air temp is 32DegC. So the boosterplug is doing its job.
Yep. The booster plug tricks the IAT read.
You can see the ECU removing fuel to negate the effect of the (false) lower temp reading. O2 sensor inputs have priority.

Do you have the flapper removed or open or catless hdrs?

You'll be running slightly richer next time you fire up your bike until the trims have time to reset.

You might put on some miles, checking your trims after rides, then repeat the process without the booster plug.
 

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Yep. The booster plug tricks the IAT read.
You can see the ECU removing fuel to negate the effect of the (false) lower temp reading. O2 sensor inputs have priority.

Do you have the flapper removed or open or catless hdrs?

You'll be running slightly richer next time you fire up your bike until the trims have time to reset.

You might put on some miles, checking your trims after rides, then repeat the process without the booster plug.
yeah, the usual, catless headers, no flapper and K&N panel filter. If the BP suppose to compensate and add up to 6-7% more fuel then I can only assume that the BP is still doing its job even with the minus values of the shot/long term trim levels.

I'm using the BP just to smooth out the low speed, small throttle opening.
 

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yeah, the usual, catless headers, no flapper and K&N panel filter. If the BP suppose to compensate and add up to 6-7% more fuel then I can only assume that the BP is still doing its job even with the minus values of the shot/long term trim levels.

I'm using the BP just to smooth out the low speed, small throttle opening.
This the can of worms. The BP is tricking the ECU into seeing colder intake air. BUT the ECU makes trim "decisions" based on the O2 sensor readings. So the IAT temp introduces a richer correction. But then the O2's see a rich mixture and trim the fuel back down. The catch is it takes a while for the ECU to trim out the BPs' effect.

I suspect your negative trims aren't bigger because of no flapper and no cat. If you run without the booster plug I suspect you'll see positive trims. About as much positive as you're negative now. There's one way to find out. :smile:

Booster plugs do trick the IAT (so I guess they are doing "their job") but on our Bosch ECU the ECU undoes the BPs' effect because it bases trims off the narrow band O2 sensors. Not all ECU's use this logic.
 

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This the can of worms.

You're not wrong! I'm slowly making my way through all the different threads on various forums on the subject.. From what I can gather the AF-XiED seems to be the best bet for me. Reasoning is that the EMS won't adapt so it's back to square one (like what happens with the BP). In addition, I think I would usually just go with a RapidBike module, but given my bike is still new (still haven't picked it up from the dealer), I like that the AF-XiED is a plug-n-play install, so easily removable prior to any dealer servicing..



I may be getting ahead of myself, given I haven't even got the bike yet, but do intend on going catless down the track, and cooler temps can't hurt. Time will tell how it goes I guess!

@JohnT you seem to be quite knowledgeable on the topic. I'm curious what you use / have used? You'd probably mentioned it throughout different posts, but I've been reading quite a bit and can't recall - but do respect your opinion.


Thanks!
 

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I'm curious what you use / have used?
I'm running a BrenTuning flash. I wanted more than a mixture correction. My other bike has a 17 yr old (original version) PCIII with a PCV waiting to be swapped in when I get the time. No flashes exist for it.
 

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I can't resist an open can of worms...

I had both the BP and the AF-XIED on my R1200GSW. I was trying to cure a lean surge at trailing throttle and small throttle openings that made the bike unpleasant in urban riding conditions. I installed the BP first, then went to the AF-XIED when I realized that the BP was just a placebo.

The first time I cold-started the bike after installing the BP, I could smell the unburned fuel in the exhaust. The bike's behavior was greatly improved for a few miles, and then the surging returned. Once I'd ridden it with the BP installed for a while, even the cold-start fueling was normal.

The AF-XIED was a different story. The purchase price was steep, but they made an immediate, lasting improvement to the throttle smoothness. They also had a meaningful adjustment range, so you could vary the settings in small increments, ride the bike for a while until the trims adjusted, then see how you like the new setting. The best part was the increase in low-rpm torque; you really could ride in a lower gear than before and get satisfactory throttle response.

It's winter in Vermont, and I bought my R Nine T in November. I haven't gone a single mile with the flapper valve deleted to see how that affects the ride, if at all. I will certainly start with AF-XIED if I decide to richen the mixture, and I won't be bothering with the BP.

One more worm for the can...
 
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After resetting my bike and riding for about 500km these are the realtime values I'm getting.
Comments?
Other than resetting the trims what else have you changed?

Have a screen shot of what you had before the reset?
 

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I can't resist an open can of worms...

I had both the BP and the AF-XIED on my R1200GSW. I was trying to cure a lean surge at trailing throttle and small throttle openings that made the bike unpleasant in urban riding conditions. I installed the BP first, then went to the AF-XIED when I realized that the BP was just a placebo.

The first time I cold-started the bike after installing the BP, I could smell the unburned fuel in the exhaust. The bike's behavior was greatly improved for a few miles, and then the surging returned. Once I'd ridden it with the BP installed for a while, even the cold-start fueling was normal.

The AF-XIED was a different story. The purchase price was steep, but they made an immediate, lasting improvement to the throttle smoothness. They also had a meaningful adjustment range, so you could vary the settings in small increments, ride the bike for a while until the trims adjusted, then see how you like the new setting. The best part was the increase in low-rpm torque; you really could ride in a lower gear than before and get satisfactory throttle response.

It's winter in Vermont, and I bought my R Nine T in November. I haven't gone a single mile with the flapper valve deleted to see how that affects the ride, if at all. I will certainly start with AF-XIED if I decide to richen the mixture, and I won't be bothering with the BP.

One more worm for the can...
AF-XIED works. The downside is it alters the mixture everywhere and doesn't just target specific areas.

Flashing the ECU you can tell the ECU to operate off of richer lambda values for "closed loop" and optimize the fuel (and ignition etc) tables so everything's "more right".
 

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AF-XIED works. The downside is it alters the mixture everywhere and doesn't just target specific areas.

Flashing the ECU you can tell the ECU to operate off of richer lambda values for "closed loop" and optimize the fuel (and ignition etc) tables so everything's "more right".
I agree completely. Tuning is the best approach, from a technical point of view.

Advantages of AF-XIED over flashing include that it's completely reversible with no checksum evidence of flashing in the ECU, if the bike ever needs to go back for warranty service. It's theoretically "safer" too: 5% more fuel everywhere isn't going to harm a lean-burn engine besides shortening the cat life, whereas an inexperienced tuner can do substantial harm. Also, it's plug and play, which appeals to those of us with enough skill to wire things up but not enough to adjust trim cells.

Disadvantages include the shotgun approach you addressed, the shorter cat life inherent in any enrichment scheme (for those of us with conscientious objections to catless pipes), and the perverse dependence of the AF-XIED on "fresh" oxygen sensors, that still have the predictable voltage slope of a new pair of narrowband sensors, which were really just designed to be glorified "switches."

Too bad there isn't more interest in the ADV Rider thread. It's long, but a great wealth of information about BMSK enrichment schemes. And Boosterplugs. :|
 
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Maybe in simplistic form, when the ECU is flash a zero value (or other value) is written to the multiplicative trim bank memory area. Maybe this write is done every time the ECU is power cycle?
 

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Maybe in simplistic form, when the ECU is flash a zero value (or other value) is written to the multiplicative trim bank memory area. Maybe this write is done every time the ECU is power cycle?
AFAIK a reset just gets you zeros, that's the point. I don't understand your - short term and + long term. NO changes or the booster plug off and on?













=
 

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Too bad there isn't more interest in the ADV Rider thread. It's long, but a great wealth of information about BMSK enrichment schemes. And Boosterplugs. :|
Yep, a long but informative read that wasn't helped any by a mod that's a BP true believer.
 
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