"cough" at 3k rpm and then dead - s4r

[Howie]

point taken.  i will contact him and ask him what the numbers mean.

to the initial question, though, would a valve clearance issue stall the engine only at 3k rpms, but run great above that?

Reread devimau's post.  In your case you are running an ECU that has not been set up yet.  Without TPS being set the UCU does not have a load/RPM relationship and there is no base line for CO.  Your bike was fine before the ECU switch, so it is unlikely, in your case, valve clearance is causing your issues.

I think the problem is we are talking about more than one bike in this thread.  My comment on valve clearance wasn't about your bike, just a generality.  Sorry if I caused any confusion.

[♣ McKraut ♣]

Have you even pulled the plugs to note their condition? This could confirm/deny your suspicion that the bike is lean.

(the flash does seem to make the white a little bit brighter than it actually looks)

front plug:


rear plug:

[booger]

those don't look lean to me, ever so subtly rich even but not lean, electrodes look like new
what you want to see is a light tan to milk chocolate brown powdery coating, any wet black sooty looking coating is a rich condition
not real sure what to make of those plugs since they look neither too lean nor too rich, however they also don't look 'just right' either
my guess is fueling isn't the issue so much as something else

[slyfox]

Maybe it is something simple, like a loose earth bolt on the ecu or the engine block.

yeaaahhhh ..... like a lousy battery .... at least on my S4R, that's the problem.

[♣ McKraut ♣]

made some changes to the keyspan adapter driver... and now it seems to be communicating with the ecu as it should.  i ran through the TPS reset process again just to be sure; that seemed to work fine (bike started up nicely even after not being fired up for about a week or so and not being on the tender).  then started up the bike to see if the gauges were looking normal, and if i could use the trimmer feature.  the gauges were responsive, but i noticed something odd.... both the air temp gauge and the speedo were reading max:



also when attempting to make changes on the trimmer (bike at about 150 degrees F), i wasn't sure that it was really saving the value i was entering (15).  but then coming back to that screen later on it did seem to still have it there.  i was told to try a value of 15 and go from there... i didn't seem to hear any noticable difference with the idle sound of the bike though going from 0 to 15... i should though, right?  do i just need to try bumping that value higher?

[♣ McKraut ♣]

okay, so in addition to the problems with air temp and speedo...do the values for throttle position, spark adv., and injection time look normal?  i hooked up the vdst last night to a friend's 848 (with genuine DP ecu) so i would have something to compare it to, but some of these values are quite different from mine.  his gauges looked thusly:

(both screens are the 848)

[Howie]

I'm a little curious why your bike is going 156 MPH at idle and the air temperature is 429 F

[DucHead]

I don't think that the your TPS can be reset using the software.  I think you need to connect to the TPS directly and use a voltmeter.

[♣ McKraut ♣]

I'm a little curious why your bike is going 156 MPH at idle and the air temperature is 429 F

you and me both.  the 848 i hooked up to immediately after had 0mph and 84 degrees.  is the ambient air temp sensor located up front near the headlight?  i'm not even sure what i do about the speedo...it works just fine on the bike.

I don't think that the your TPS can be reset using the software.  I think you need to connect to the TPS directly and use a voltmeter.

hmm... everything i've heard so far indicates that it's purely software... just a couple mouseclicks, wait for it to do a seven or eight second countdown, it says "PASS", and then you turn the ignition off and wait for 13 seconds, and turn it back on.

[ducpainter]

I don't think that the your TPS can be reset using the software.  I think you need to connect to the TPS directly and use a voltmeter.

That was the case with the earlier bikes.

Somewhere along the line it became a software item.

[devimau]

judging by the spark pic and the values in the screen that map on the ecu is way off IMMO.
the trimming looks ok (outer part of the plug) but the map itself is way lean and is detonating (look @ the porcelain and tip, very withe and alum residue).
the screen shows all parameters ok but the speed, temp and I'm not sure about that spak advance, tps and other values are fairly in spec.
who did the ecu remap?

[♣ McKraut ♣]

judging by the spark pic and the values in the screen that map on the ecu is way off IMMO.
the trimming looks ok (outer part of the plug) but the map itself is way lean and is detonating (look @ the porcelain and tip, very withe and alum residue).
the screen shows all parameters ok but the speed, temp and I'm not sure about that spak advance, tps and other values are fairly in spec.
who did the ecu remap?

bobby at desmo-porche

[devimau]

I never dealt with him so I don't know how accurate his maps are.
you should call him and show him the spark and  vdst pics along with your co values info and go from there.

[DucHead]

That was the case with the earlier bikes.

Somewhere along the line it became a software item.

Hmmm...the OP has the same nonlinear TPS as me, and according to Moto1, it cannot be reset with the VDTS.

[ducpainter]

Hmmm...the OP has the same nonlinear TPS as me, and according to Moto1, it cannot be reset with the VDTS.

I'm sure you're right Dave.

There was some discussion of which ecu he has, and I don't know when it became a software item.