ADVrider

Go Back   ADVrider > Bikes > GSpot > Parallel Universe
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 05-18-2013, 06:54 PM   #91
SOP Dirt-Rider
Studly Adventurer
 
SOP Dirt-Rider's Avatar
 
Joined: Aug 2012
Location: Port Orchard, WA
Oddometer: 664
Plug the hose with a suitable bit (I used a wire twist tie with the ears trimmed off) and than replace the hose onto the solenoid. No error readings.

I did the same thing on my C14 when I installed the AT. Just dynoed 162 RWHP yesterday....
SOP Dirt-Rider is offline   Reply With Quote
Old 05-19-2013, 09:54 PM   #92
jscottyk OP
Gnarly Adventurer
 
jscottyk's Avatar
 
Joined: Apr 2007
Location: Austin, Texas
Oddometer: 329
Gaspare posted some testing SAS over at the Dynojet PC-5, with Autotune thread today but considering it's relevence to this thread I'm going to quote it here.

Quote:
Originally Posted by Gaspare View Post
Test done!
So, accordingly with the BMW SW update available on 2011, March – and not modified during the reflashing – the SAS behaves as follow.

In neutral and first three gears: ON during all the way opening throttle and stays ON during steady states, too.
When you close the throttle it turns OFF ‘till 3000 rpm (decreasing rpm),then ON again.
Obviously, if you accelerate within 3000 rpm, the SAS keep ON during the throttle closing, too.

In 4th, 5th and 6th gear, SAS during acceleration turns OFF at a certain rpm (Trottle Opening).
During deceleration, it turns ON again at a certain rpm (Throttle Closing).
4th – TO=3000 rpm; TC=2900 rpm
5th – TO=2600 rpm; TC=2500 rpm
6th – TO=2500 rpm; TC=2400 rpm (everywhere ±50 rpm)

So, with a certain hysteresis, (4th, 5th and 6th) SAS is ON below 3000-2600-2500 and OFF over these rpms – where is possible to do whatever you want (WOT, etc.) and SAS keeps OFF.

With SAS disconnected I haven’t noticed any sensible change in performance or throttle reply; quite a windy day – so I’m not sure at 100%.
Surely, the popping tendency @ SAS back ON is almost decreased; then, when I tried richer settings, a single BIG-POP was always present at the rpm where now I do know SAS is returning ON, no matter how I was decelerating…

It does make sense the SAS OFF is equivalent at where we could expect the λ validated readings, or at least is a proper subset…
Currently these two threads are orbiting closely but the above quote might help when someone finds this in later searches.
jscottyk is offline   Reply With Quote
Old 05-20-2013, 06:37 AM   #93
roger 04 rt
Beastly Adventurer
 
roger 04 rt's Avatar
 
Joined: Nov 2011
Location: Massachusetts
Oddometer: 2,125
The fact that the SAS point changes at a lower RPM as you go higher in the gears is indicative of it being tied to throttle-angle/manifold-vacuum. I heard this from a designer too.
RB
roger 04 rt is offline   Reply With Quote
Old 05-20-2013, 11:35 AM   #94
Bayner
Beastly Adventurer
 
Joined: Mar 2008
Location: Penticton, BC
Oddometer: 1,475
If you were running an autotune setup and still retaining the cat converter then don't you still need the SAS functioning? I would assume they have enough air for emissions management but not enough to screw up their own sensor readings, right?
... Or do the instances of SAS activation and closed loop not overlap on a stock bike?
Bayner is offline   Reply With Quote
Old 05-20-2013, 12:45 PM   #95
SOP Dirt-Rider
Studly Adventurer
 
SOP Dirt-Rider's Avatar
 
Joined: Aug 2012
Location: Port Orchard, WA
Oddometer: 664
Quote:
Originally Posted by Bayner View Post
If you were running an autotune setup and still retaining the cat converter then don't you still need the SAS functioning? I would assume they have enough air for emissions management but not enough to screw up their own sensor readings, right?
... Or do the instances of SAS activation and closed loop not overlap on a stock bike?
No. I am trying to remember, is the 02 sensor before, or after the cat, I would hazard a guess it is before the cats. I would also hazard a guess the reason as to why BMW uses a narrow band is to tie in with the SAS, IOW no readings when the valve is open and hence the complexity. All in the name of lowering emissions on an already emission friendly vehicle
SOP Dirt-Rider is offline   Reply With Quote
Old 05-20-2013, 01:06 PM   #96
jscottyk OP
Gnarly Adventurer
 
jscottyk's Avatar
 
Joined: Apr 2007
Location: Austin, Texas
Oddometer: 329
Quote:
Originally Posted by SOP Dirt-Rider View Post
No. I am trying to remember, is the 02 sensor before, or after the cat, I would hazard a guess it is before the cats. I would also hazard a guess the reason as to why BMW uses a narrow band is to tie in with the SAS, IOW no readings when the valve is open and hence the complexity. All in the name of lowering emissions on an already emission friendly vehicle
Looks like before.
jscottyk is offline   Reply With Quote
Old 05-20-2013, 02:00 PM   #97
roger 04 rt
Beastly Adventurer
 
roger 04 rt's Avatar
 
Joined: Nov 2011
Location: Massachusetts
Oddometer: 2,125
Quote:
Originally Posted by Bayner View Post
If you were running an autotune setup and still retaining the cat converter then don't you still need the SAS functioning? I would assume they have enough air for emissions management but not enough to screw up their own sensor readings, right?
... Or do the instances of SAS activation and closed loop not overlap on a stock bike?
The instances of Closed Loop and SAS cannot overlap. The narrowband O2 sensor is very sensitive to ANY oxygen.

SAS is incompatible with Autotune.

If you run a Powercommander without Autotune but with SAS enabled you will get exhaust system heating. How much I do not know.

When you run a Power Commander or LC-1 richer than 14.2:1, the catalytic converter doesn't do much to oxidize unburned fuel or carbon monoxide,NAND carbon monoxide increases rapidly with richness.

The catalytic converter stores oxygen. When it uses oxygen to eliminate unburned hydrocarbons and to convert carbon monoxide to carbon dioxide it uses up what has been stored

The catalytic converter gets oxygen from three sources: 1) the lean half of the Closed Loop rich/lean cycle; 2) the reduction of NOx to NO2; and during Overrun Fuel Cutoff. The oxygen is stored in a chemical called Cerium. SAS might help add oxygen but I believe there is no way it can be compatible with Autotune.

It's a complicated process, I hope this adds some understanding.
roger 04 rt is offline   Reply With Quote
Old 05-21-2013, 05:59 PM   #98
ebrabaek
Beastly Adventurer
 
Joined: Jan 2010
Location: Grand Valley, Colorado
Oddometer: 4,674
Quote:
Originally Posted by jscottyk View Post
A couple of images for reference.

I think the valve that controls air to the SAS is #17 in this image.

Part #19 from the above images is #4 in this image.


The connector from BMS-K should attach to #17.
Can anyone confirm where hose # 2 goes.....????? From side of the valve cover....to ...???????
__________________


Erling
ebrabaek is offline   Reply With Quote
Old 05-21-2013, 07:04 PM   #99
roger 04 rt
Beastly Adventurer
 
roger 04 rt's Avatar
 
Joined: Nov 2011
Location: Massachusetts
Oddometer: 2,125
Isn't that the crankcase vent which goes to the air box?

And hose 4 the SAS hose going to the valve on the airbox?
roger 04 rt is offline   Reply With Quote
Old 05-21-2013, 07:34 PM   #100
jscottyk OP
Gnarly Adventurer
 
jscottyk's Avatar
 
Joined: Apr 2007
Location: Austin, Texas
Oddometer: 329
Quote:
Originally Posted by roger 04 rt View Post
Isn't that the crankcase vent which goes to the air box?

And hose 4 the SAS hose going to the valve on the airbox?
That is my understanding.
jscottyk is offline   Reply With Quote
Old 05-21-2013, 08:14 PM   #101
roger 04 rt
Beastly Adventurer
 
roger 04 rt's Avatar
 
Joined: Nov 2011
Location: Massachusetts
Oddometer: 2,125
So here's what we know


There is a secondary air system.
Fresh air can enter the exhaust by way of this system.
The purpose of allowing the fresh are is to oxide unburned fuel (when mixture is rich) not to alter the performance of the engine
SAS airflow will create an autotune error.

Air can only flow through SAS when:
a) BMSK says it can, and
b) when the pressure in the exhaust is less than ambient pressure.
Pressure at the exhaust side of the reed is low just after the exhaust valve closes following the exhaust stroke.

Therefore there should not be a significant impact on VE. Meaning it should not affect running of the engine.

So I would begin by removing the connector to the SAS valve.

Then I would create a base map that is close to what I expect to need to hit the targets in the Target AFR Map.

Then ride it with that map installed and see how it feels. The closer you get the base map, the easier it will be for Autotune to work accurately.

Then after a ride with Autotune off, i would ride with Autotune on and see what it does.
roger 04 rt is offline   Reply With Quote
Old 05-21-2013, 08:25 PM   #102
roger 04 rt
Beastly Adventurer
 
roger 04 rt's Avatar
 
Joined: Nov 2011
Location: Massachusetts
Oddometer: 2,125
Btw, plugging starting values into the base map is a direct analogy to what we do with the LC-1. To make it faster for the BMSK to create its adaptation values (and since we don't have a trim table) we add a BoosterPlug which adds a flat 6% to every cell. Or on the 1150 either a BoosterPlug or a fuel pressure increase for the same reason, to add fuel to every cell.

On the 1150 we don't have to worry about the trip computer miscalculating mileage (from higher fuel pressure) because there is no trip computer. If there was a trip computer the BoosterPlug would not interfere but the fuel pressure increase would. The reason is when you change air temp the ECU is in on the calculation (unwittingly) whereas the fuel pressure increase would be unknown to it.
roger 04 rt is offline   Reply With Quote
Old 07-06-2013, 09:55 AM   #103
roger 04 rt
Beastly Adventurer
 
roger 04 rt's Avatar
 
Joined: Nov 2011
Location: Massachusetts
Oddometer: 2,125


Jscottyk is running a beta test on a BMW-AF-XIED for me on his F800GS. In the process he's taken delivery of a GS-911 and has been sourcing some very interesting data on the F800GS's Secondary Air Valve, along with info on the beta device.

From what we've seen so far, we can confirm most of the functions mentioned by Gaspare in his quoted report below. In the chart above, we've captured a good idea of just how often the SAS valve is open--much of the time. In fact, it's open so much that it is almost easier to describe when it isn't open.

The biggest finding from the chart below is that the BMS-K appears to be able to run its Closed Loop program, with the stock narrowband O2 sensor, even with SAS enabled. I've done some reading that suggests that its effect can be taken into account by the Closed Loop algorithm. It is still very likely though that it would affect the reading of a Wideband O2 sensor like the LC-1 or PC-V which would have no way of knowing about the Valve.

Looking at the chart below (ignore the axis on the right side which I've used to move the top two high low plots to the top where they can be seen), the top line indicates when the BMS-K is running in Closed Loop. When the line is at the high level it's Closed, when at the low level it is Open Loop.

Next is the SAS Valve. High state means the valve is Open, Low state means that it is Closed Loop.

The next three lines are gear position, RPM/1000 and TPS/10 the values are indexed to the left hand axis and have been scaled so they fit on the same chart.

The easiest conclusion to draw is that SAS is Open in 1st, 2nd and 3rd, and Closed in 4th, 5th and 6th. It is also closed for a moment if you abruptly close the throttle and for a moment if you suddenly pull in the clutch.

From reading, the SAS valve is primarily an emmissions reduction valve, especially helping to warm the CAT after a cold start. It probably has some effect on Closed Loop lambda but in order for the CAT to work the BMSK must have a way to take that into account.

Great thanks to jscottyk for his ongoing efforts to collect and help me analyze this information. He will no doubt report on the BMS-AF-XIED at a later time.

RB

Quote:
Originally Posted by jscottyk View Post
Gaspare posted some testing SAS over at the Dynojet PC-5, with Autotune thread today but considering it's relevence to this thread I'm going to quote it here.

Quote:
Originally Posted by Gaspare
Test done!
So, accordingly with the BMW SW update available on 2011, March – and not modified during the reflashing – the SAS behaves as follow.

In neutral and first three gears: ON during all the way opening throttle and stays ON during steady states, too.
When you close the throttle it turns OFF ‘till 3000 rpm (decreasing rpm),then ON again.
Obviously, if you accelerate within 3000 rpm, the SAS keep ON during the throttle closing, too.

In 4th, 5th and 6th gear, SAS during acceleration turns OFF at a certain rpm (Trottle Opening).
During deceleration, it turns ON again at a certain rpm (Throttle Closing).
4th – TO=3000 rpm; TC=2900 rpm
5th – TO=2600 rpm; TC=2500 rpm
6th – TO=2500 rpm; TC=2400 rpm (everywhere ±50 rpm)

So, with a certain hysteresis, (4th, 5th and 6th) SAS is ON below 3000-2600-2500 and OFF over these rpms – where is possible to do whatever you want (WOT, etc.) and SAS keeps OFF.

With SAS disconnected I haven’t noticed any sensible change in performance or throttle reply; quite a windy day – so I’m not sure at 100%.
Surely, the popping tendency @ SAS back ON is almost decreased; then, when I tried richer settings, a single BIG-POP was always present at the rpm where now I do know SAS is returning ON, no matter how I was decelerating…

It does make sense the SAS OFF is equivalent at where we could expect the λ validated readings, or at least is a proper subset…


Currently these two threads are orbiting closely but the above quote might help when someone finds this in later searches.
Jscottyk is running a beta test on a BMW-AF-XIED for me on his F800GS. In the process he's taken delivery of a GS-911 and has been sourcing some very interesting data on the F800GS's Secondary Air Valve, along with info on the beta device.

From what we've seen so far, we can confirm most of the functions mentioned by Gaspare in his quoted report above. In the chart below, we've captured a good idea of just how often the SAS valve is open--much of the time. In fact, it's open so much that it is almost easier to describe when it isn't open.

The biggest finding from the chart below is that the BMS-K appears to be able to run its Closed Loop program, with the stock narrowband O2 sensor, even with SAS enabled. I've done some reading that suggests that its effect can be taken into account by the Closed Loop algorithm. It is still very likely though that it would affect the reading of a Wideband O2 sensor like the LC-1 or PC-V which would have no way of knowing about the Valve.

Looking at the chart below (ignore the axis on the right side which I've used to move the top two high low plots to the top where they can be seen), the top line indicates when the BMS-K is running in Closed Loop. When the line is at the high level it's Closed, when at the low level it is Open Loop.

Next is the SAS Valve. High state means the valve is Open, Low state means that it is Closed Loop.

The next three lines are gear position, RPM/1000 and TPS/10 the values are indexed to the left hand axis and have been scaled so they fit on the same chart.

The easiest conclusion to draw is that SAS is Open in 1st, 2nd and 3rd, and Closed in 4th, 5th and 6th. It is also closed for a moment if you abruptly close the throttle and for a moment if you suddenly pull in the clutch.

From reading, the SAS valve is primarily an emmissions reduction valve, especially helping to warm the CAT after a cold start. It probably has some effect on Closed Loop lambda but in order for the CAT to work the BMSK must have a way to take that into account.

Great thanks to jscottyk for his ongoing efforts to collect and help me analyze this information. He will no doubt report on the BMS-AF-XIED at a later time.

RB

roger 04 rt screwed with this post 07-06-2013 at 01:12 PM
roger 04 rt is offline   Reply With Quote
Old 07-06-2013, 06:40 PM   #104
jscottyk OP
Gnarly Adventurer
 
jscottyk's Avatar
 
Joined: Apr 2007
Location: Austin, Texas
Oddometer: 329
Thanks for the update Roger! That is a a much clearer explanation than I could ever describe. Plus, you excel chart making skills are far superior to mine!

Everyone, keep an eye on the Wideband O2 Sensor for F800S/GS thread. I'll be posting my experiences with one of the BMW-AF-XIED beta units very soon. The short story is WOW. You guys are going to like this!
jscottyk is offline   Reply With Quote
Old 01-31-2014, 09:37 PM   #105
roger 04 rt
Beastly Adventurer
 
roger 04 rt's Avatar
 
Joined: Nov 2011
Location: Massachusetts
Oddometer: 2,125
Since my last post, with the benefit of the GS-911 data, and the mixture adaptation tests I reported on recently (beginning here at post #358), I've got a different view of how the SAS system is intended to function and its purpose. It will sound like double-talk, and I will contradict some comments I made earlier in the thread.

It appears that the SAS system is operational during light loads and when the BMSK is running Closed Loop. Its purpose is to cause the BMSK to richen the combustion mixture during the time SAS operates by "fooling" the stock O2 sensor. If you accept that contention for a moment, I'll try to explain.

Looking at the beginning and end of the chart below, the motorcycle is: idling, with SAS on, and operating in Closed Loop. That is a condition that isn't too hard to analyze.

First though, imagine that SAS was OFF. The Closed Loop program running in the BMSK, will move fueling until lambda at the O2 sensor varies a bit above and a but below lambda=1 (gasoline AFR 14.7:1). Now while the bike is stable, and idling, turn the SAS valve on, a little fresh air will be drawn into the exhaust past the SAS reed valve during those moments just after the exhaust valve closes. The O2 sensor will register this as leanness, the BMSK will measure it and add a little fuel to the mixture (richening it!) until lambda at the O2 sensor is once again stable at lamda=1. Through the BMSK Mixture Adaptation process it "learns" about the need for this bit of extra fuel and even supplies it under the same load/rpm combinations during Open Loop fueling.

The purpose of SAS can then be seen as a way, in a closed loop system, to bias the O2 sensor toward leanness at light loads, so the BMSK has to add a little fuel to overcome the lean bias. The slightly richer mixture results in a better idle, less "surging" behavior at light loads, and less exhaust popping from a too-lean mixture under light-load-deceleration.
RB

roger 04 rt is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 10:12 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014