[gashousegorilla]

Gashousegorilla - I think I disagree with your final paragraph.  I think it injects more fuel on a cold start (as determined by the engine temp. sensor) to make a richer mixture.  Unfortunately it has no way of opening the throttle (or air bypass) to give a faster idle, so it relies on the user doing that.  Terrible bodge.

  It does, I was referring to a cold idle vs a hot idle..... not a cold start.  When the kill switch is turned on and the pump spins up and pressurizes, the injector also fires a shot of fuel at the intake .  Sort of like ?..... tickling a Amal  carb and kicking it through a time or two to wet the cylinder.  And again it comes on as you hit the starter or start to kick.  The amount of fuel cycled across the range is determined by the base setting Voltage on the tps, which IS adjustable .  With everything set right, your should just have to hit the start button without touching the throttle and hold down the by-starter for a few ..... maybe a little more when it really cold out?   But certainly the whole process should be around two minutes.  That's what I have found, and what others have reported.

  Those base/ starting settings for set up the bike are.....  5 degree's open at the throttle plate... throttle plate adjuster screw.  3/4 turn out from a seated position on the air screw and .6v  at the tps.  The tps is a potentiometer and can be adjusted independently from the throttle plate.

[gremlin]

............. how is Bi-starter different from opening the throttle at handlebar !

Bi-starter increases barometric pressure in the intake manifold just like blipping the throttle, however, the Throttle position sensor is unmoved - so - the ECM can add more fuel to account for the lower altitude, without enriching the mixture for acceleration.

[SteveThackery]

Hey, gashousegorilla!  Thanks for the info about the set-up adjustments.

Question for you: what does that screw do that looks like it ought to be the idle speed control but isn't.  Is that the one that sets the "closed" throttle plate angle of 5 degrees?  And how do you adjust the potentiometer to set the 0.6V? 

I haven't had a good look at the throttle body, as you can probably tell.

[singhg5]

Ace.cafe: What you say certainly makes sense, although Wikipedia seems to imply that the lambda sensor generates the voltage itself, rather than having (essentially) a variable resistance.

To understand oxygen sensor readings, it is helpful to know what is it made of and how it works.

Binary Type Oxygen Sensors

There are two types of Binary oxygen sensors i) Zirconia sensor and ii) Titania sensor. They use different types of ceramic element and function differently but achieve same goal of complete combustion of fuel.

Zirconia type are made of Zirconium dioxide ceramic hollow body, that holds ambient air as reference. A thin porous layer of platinum is applied on either side of body that function as electrodes to carry signal. At temperatures of 300C, zirconia transfers oxygen ions that create voltage. The greater the difference of oxygen concentration between exhaust gas and reference air, the higher the voltage produced.

The voltage production is thus a property of this element used to make them. In lean conditions, voltage is about 0.1V and in fuel rich (no oxygen) it is 0.9V.

Here is important part - There is VERY SHARP change in voltage around the stoichiometric point. So the readings are always in a big flux from high to low quickly and back up as fuel injector adjusts fuel.

Titania Type sensors look the same as above but these sensors do NOT generate voltage. They offer electrical resistance which changes with oxygen concentration. In a lean mixture (lots of oxygen), the resistance increases. When there is rich mixture (no oxygen), the resistance decreases.

Titania sensors alter the voltage of signal that is supplied by computer ECU.

At the stoichiometric point there is a LARGE change in resistance. These sensors respond faster and are smaller than zirconia type. They have internal heating element.

Essentially the system oscillates between 'Oxygen' and 'No Oxygen' which is read as either 0.9V or 0.1V. The intermediate values quickly slide up or down because of steep slope of the curve as the fuel is altered back and forth.

Pause here because RE has Binary Lambda sensor.

[gremlin]

.........I wonder why the ECU sends that 4.7V to the lambda sensor.  Perhaps we will discover that in due course...........

That is a *fluke* of your test setup.  your meter is very high impedance, and, an O2 sensor is very low impedance.

I believe the 4.7 volts you are reading are actually a leakage from the feedback of the OP-AMP comparator circuit that is being driven by the low impedance output of the O2 sensor.

In other words .....  inconsequential under normal operation.

[gremlin]

I guess we need to know which part is correct for the Khelin injection system.

[singhg5]

Bi-starter increases barometric pressure in the intake manifold just like blipping the throttle, however, the Throttle position sensor is unmoved - so - the ECM can add more fuel to account for the lower altitude, without enriching the mixture for acceleration.

Yes, now I can confirm this.

I just tested MAP sensor output voltage at idle without touching the throttle. Its voltage changed when Bi-starter lever was pulled down (opened the bypass). So the MAP sensor does detect this small addition of air into intake manifold.

It is however different in another way from just opening the throttle at handlebar because throttle plate is not moved so TPS voltage should not change with Bi-starter.

Another phenomenon observed with Bi-starter is that after 20 seconds in a hot engine and about 100 seconds in a cold engine, the effect of Bi-starter on idle rpms is completely gone - even though it is still open - the engine returns to its original rpms before using Bi-starter. Somehow ECU or something overrides Bi-starter after some cut off time or another sensor takes over ... up for more ideas how this happens.   

[gashousegorilla]

   No it didn't Singh. I DO have a cheater installed at the o2 sensor plug.... But that is JUST to let ECU "think "  that there is a o2 sensor in the circuit. Sooo, even with the cheater, there is no feed back to the ECU as far as AFR's go.  I think we may be paying too much attention to the o2 sensor ...... Although very worthy of study !.... when fueling is controlled by the TPS, And the o2 sensor is just a switch between too rich and too lean for emissions.

 And I noticed a similar behaviour to yours, back when I was messing around with the map sensor.   With it removed the bike would run like crap..... you would need a fist full of throttle to keep the bike running. That may have been because I created a vacuum leak with it removed ?!  LOL,   but I'm remembering it not being much better with the orifice plugged.  This was also in conjunction with testing Cams and a new intake.. BOTH WILL change the results I get and what you get.   Manifold pressure IS different with Cams in particular.   So my blip in voltage , may be less pronounced then in yours, especially with stock intake and cams.

 
 This may help..... You can tune across the range with TPS voltage. Higher base voltage  say.... .65v is RICHER across the range then .60v.  58v is leaner across the range.  And this works and I have done it with different intake's exhausts and head work. However.... when we got into Cams , you needed to pull fuel out in certain area's, especially down low, then radically add fuel as the RPM's come up.  So with cams, and depending on how aggressive. They WILL effect manifold pressure... less vacuum at idle, however increased exponentially will RPM's. Same with cranking compression Vs, Dynamic compression.



@GHG

Interesting that without oxygen sensor you got same results as me ! So oxygen sensor did not play a role in changing the rpms when Bi-starter valve was opened ! 

Mystery upon mystery  .

More discussion later ..........go to go.
[/quote]

[gashousegorilla]

Hey, gashousegorilla!  Thanks for the info about the set-up adjustments.

Question for you: what does that screw do that looks like it ought to be the idle speed control but isn't.  Is that the one that sets the "closed" throttle plate angle of 5 degrees?  And how do you adjust the potentiometer to set the 0.6V? 

I haven't had a good look at the throttle body, as you can probably tell.

  Singh5 has some very informative video's , and I he may have a video showing all of these functions.   

The throttle plate stop screw, is on the riders right side of the TB.  looks like a short piece of threaded rod, with a small hex nut.  Allan headed top of the rod as I remember?


 The idle adjustment is in a well, large brass screw on the top tear of the TB.


  The TPS is on the riders left side of the TB. Three wire sensor, with a torx head set screw. There is an elongated slot that the the torx headed set screw resides in.  Potentiometer....
 Again..... adjusting your throttle plate will alter tps voltage. HOWEVER.... adjusting the tps ONLY will not change the throttle plates position. I doubt however, that your throttle plate or tps voltage needs to be changed..... but worth checking it's volage.  If those two are ok ?  Then it is in the idle screw that needs adjustment. Do it on a hot bike.... at operating temp. If you do it when the bike is cold, you will likely find that your idle is tooo high when hot. It may race and it may surge from a overly lean idle.... My findings anyway.

[gashousegorilla]

This discussion is most interesting.

Hopefully it's not a hijack, but... I wonder if through this careful deliberation about what is happening with the EFI, you smart guys will come up with a possible explanation for the idle speed stalling-with-throttle problem which some of the GT guys have had, and I have begun to have again after 6000 miles...

 Matt, I spoke to a gentleman today at the Bike show in Brooklyn who owns a GT, as well as a G-5 and I believe he said a B-5 as well ?   His observations of the GT's behaviour anyway, are that it behaves like his other bikes. And it's not an issue..... 

[mattsz]

GHG - remember the GT threads that were lost?  It was a busy discussion topic there, one that I haven't heard reached a satisfactory conclusion.

Matt,

Maybe it was a "once a while" stall issue. Or are you having this issue often now? On my B5, it is so rare now. If you're at the lights and the idle goes down, just give the throttle a blip and it settles down to a nice tick-over. Being a long stroke 500 single, they do sometimes require some throttle here and there. Clean the air-filter too!

Five or six times a week.  Some GT guys were seeing it regularly.  To be clear, my bike idles perfectly, needs no throttle to hold it.  But when you drop it into gear, turn the throttle to move off, the bike dies.  Or, if you're just idling in neutral, and it's ready to happen, turn or blip the throttle and it stalls.  Totally random - sometimes when just warming up, sometime when hot.

Regarding these grand experiments, maybe this is a dumb question, but... Keihin must know all these answers already - has anybody asked them, or the RE engineers?  Or, is it proprietary info they won't share?

[gashousegorilla]

GHG - remember the GT threads that were lost?  It was a busy discussion topic there, one that I haven't heard reached a satisfactory conclusion.

Five or six times a week.  Some GT guys were seeing it regularly.  To be clear, my bike idles perfectly, needs no throttle to hold it.  But when you drop it into gear, turn the throttle to move off, the bike dies.  Or, if you're just idling in neutral, and it's ready to happen, turn or blip the throttle and it stalls.  Totally random - sometimes when just warming up, sometime when hot.

Regarding these grand experiments, maybe this is a dumb question, but... Keihin must know all these answers already - has anybody asked them, or the RE engineers?  Or, is it proprietary info they won't share?

 Yes I do.   And GOOD luck getting anything from Keihin !    I'm still trying to figure out what the Base timing curve is..... It varies I know but geez !  BTW, your problem to me, sounds like there may be an issue with the neutral or clutch switch.... or the circuit.

[mattsz]

Yes I do.   And GOOD luck getting anything from Keihin !    I'm still trying to figure out what the Base timing curve is..... It varies I know but geez !  BTW, your problem to me, sounds like there may be an issue with the neutral or clutch switch.... or the circuit.

I think that's bull$hit - we ought to be told how our bikes work if we ask.  Oh well.  And you guys are going to figure it out anyway... 

As for the stalling: neutral or in gear; neutral light on or off; clutch in or out; doesn't make a difference.  But it's possible, I suppose.  I don't remember that suggestion coming up for the GTs.  As I recall, one guy solved it by making adjustments to his TPS?  Or was it the butterfly opening?

[JVS]

Five or six times a week.

How much free-play do you have at the throttle grip side? Check your throttle body hose and air-filter to throttle body hose for any cracks or damage. Check air-filter for oil residue, clean. Also, when you accelerate from a start, do not give it a gentle roll on of the throttle. Make it a bit more deliberate.

[gashousegorilla]

I think that's bull$hit - we ought to be told how our bikes work if we ask.  Oh well.  And you guys are going to figure it out anyway... 

As for the stalling: neutral or in gear; neutral light on or off; clutch in or out; doesn't make a difference.  But it's possible, I suppose.  I don't remember that suggestion coming up for the GTs.  As I recall, one guy solved it by making adjustments to his TPS?  Or was it the butterfly opening?

     "Fanny Adams" right, it's BS  Matt !    I could be wrong, but i thought you had mentioned that the bike was Ok for a bunch of miles and it started acting up ?

 And I'm pretty  sure Jimmy in the GT section wisely found it was not the TPS adjustment. But an issue with his Throttle plate adjustment.  I think he closed it off and slightly cracked it open, forcing more air through the by-pass, which seemed to have helped.