Fueling without cam sensors

Nice work Max! Interesting how it works. Not exactly how I would have thought.

Would be interesting to put a scope on them. Mine is only a 2 channel scope. Might have to invest in a 4 channel.. Where is the thinking, thinking emoji? :D
 
:huh: :huh: :huh: :huh: :idea:
 
max_imp said:
For the benefit of mr Norris et all ( not mr K ) here is a video clip that shows in slow motion what the injectors are doing when the engine fires up from cold.

Two led's are connected across injectors 1 and 4, they light up when the injectors are operated, there is one double firing at the start button push and then another four double shots of fuel into both ports.
After what seems like a small pause the no1 cylinder fires and then no4 cylinder and so on.

It appears that the double dose just gets the ( cold ) engine going and the decision ( electronic dice ) is then made by firing one cylinder at a time and waiting for the crank sensor to report a higher frequency at which time success is registered and the engine runs in the " uneven " sequence.
There is a lot more to this of course but now we know a bit more about what actually happens.

You all may have noticed that it takes the cb1100 to always take a bit of time to start up even if it is warm, the next question is; what if the engine is bump started, does it remember in what sequence it was before it stopped?

The clip is slowed down to 7% speed but the pitch of the sound remains the same hence the eery soundtrack, the unusual firing of the led's once the engine is running is the result of the frame rate and rev's mismatch and appears out of sync, in reality they fire at the correct time and sequence, i had a hard time getting this part as best i could on video;

And Joe, would you be able to tell us what the clearances and shim sizes were before and after so we can complete this thread here;
http://cb1100forum.com/forum/showthread.php?tid=8882&pid=139671#pid139671
That was interesting.
 
Cormanus_imp said:
:huh: :huh: :huh: :huh: :idea:
Oh, man. Its early here. I guess I need more coffee :-/

I have seen one that thinks and moves back and forth. But we don’t have that one.
 
Lord Popgun_imp said:
Cormanus_imp said:
:huh: :huh: :huh: :huh: :idea:
Oh, man. Its early here. I guess I need more coffee :-/

I have seen one that thinks and moves back and forth. But we don’t have that one.
Oh, man. Its early here. I guess I need more coffee :-/

I have seen one that thinks and moves back and forth. But we don’t have that one.
"more" coffee? Not sleepin'? :-/
 
GoldOxide_imp said:
Lord Popgun_imp said:
Cormanus_imp said:
:huh: :huh: :huh: :huh: :idea:
Oh, man. Its early here. I guess I need more coffee :-/

I have seen one that thinks and moves back and forth. But we don’t have that one.
Oh, man. Its early here. I guess I need more coffee :-/

I have seen one that thinks and moves back and forth. But we don’t have that one.
"more" coffee? Not sleepin'? :-/
Oh, man. Its early here. I guess I need more coffee :-/

I have seen one that thinks and moves back and forth. But we don’t have that one.
"more" coffee? Not sleepin'? :-/
Oh man, I drink a LOT of coffee. Even in the Summer. And I don’t do ANYTHING unless I have it. I don’t care what your emergency is! :D
 
Lord Popgun_imp said:
GoldOxide_imp said:
Lord Popgun_imp said:
Cormanus_imp said:
:huh: :huh: :huh: :huh: :idea:
Oh, man. Its early here. I guess I need more coffee :-/

I have seen one that thinks and moves back and forth. But we don’t have that one.
Oh, man. Its early here. I guess I need more coffee :-/

I have seen one that thinks and moves back and forth. But we don’t have that one.
"more" coffee? Not sleepin'? :-/
Oh, man. Its early here. I guess I need more coffee :-/

I have seen one that thinks and moves back and forth. But we don’t have that one.
"more" coffee? Not sleepin'? :-/
Oh man, I drink a LOT of coffee. Even in the Summer. And I don’t do ANYTHING unless I have it. I don’t care what your emergency is! :D
So, could it be subliminal statements like, "cuffeecuffeecuffee" gets your motor going?
 
Like Max said, double shots get it going and single after that :)
 
Ideally you need an automotive " graphing " scope like a picoscope, the one that draws lines on the screen or in old terms a memory scope.

"I have seen one that thinks and moves back and forth. But we don’t have that one." yeah that's what i mean Popgun, it's gotta "thinks".:rofl:

And i only have a 20 meg dual channel that does not get used often but that would only get you some meaningless pulses on the screen, it happens too quick to watch, in real time you don't see anything meaningful, it needs to slow down 20 times to find out what's happening.

All i did was push some 4k7 resistors with one lead into the injector connector's rubber seals at the top ( they are still in there ) and connected two led's to them, maybe i can couple another led capacitively with the ignition lead and show that on video too, see what happens, that would be cool.:idea:

The pulses would show up fine when the video editor was slowed down but when the clip was rendered it would be a mess of blinking lights, i tried all sorts of speed reductions but it wasn't until i rendered in 60 frames per second that it showed up clearly enough to upload to youtube.

The audio graph was also interesting to look at, it showed that the injectors fired after the compression stroke when there was least resistance of the starter motor.

Maybe i could have one of the led's in a different color look at the primary ignition coil and see the relationship with the spark; does it fire every time or only after there is enough fuel dumped into the cylinders after some strokes?
 
Thread starter
Brilliant work, Max!

I knew the ECM had to re-learn the crank/cam phase relationship every time you start the engine, because for every crank position there are two possible cam positions.

Rolling the electronic dice and noting the results (in terms of slight crank speed variations) would be one way to do it. Thanks for solving that mystery for us!

--Joe

ps I'll go back and look at my spreadsheet records and note what the measured clearances were and what shims were/are in place. Strangely, all four valves on my #1 cylinder were at the tight end of the spec range this time--all other valves were right in the center of the range where I had set them 8,000mi prior.
 
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