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1Back to top Go down   Our EFI systems Empty Our EFI systems Sun Nov 08, 2015 4:56 am

floyd

floyd
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Not sure where to put this, so here is as good as anywhere...

So our EFI systems (Jetronic and Motronic) open all 4 injectors simultaneously on each stroke. Correct?

So that means that there would be fuel 'pooling' behind the inlet valve until it opens? Resulting in more fuel than 'required' making its way into the combustion chamber? Is that correct?

Does the computer take that in to account when calculating fuel/air mix?

Sorry for what may be a trivial question...it juts puzzles me and I know some of you will be able to give me a great explanation Wink


__________________________________________________
K100 with lots of K1100 bits - mongrel of a thing...
    

2Back to top Go down   Our EFI systems Empty Re: Our EFI systems Sun Nov 08, 2015 6:03 am

RicK G

RicK G
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At 100 kph and getting 20k/l each injector sprays 0.0031 millilitres of fuel at each revolution, twice that at each valve opening. Considering that the port temperature would be around 100°C I really dont think that pooling will be a problem.  33 valve openings per second that work out to.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

3Back to top Go down   Our EFI systems Empty Re: Our EFI systems Sun Nov 08, 2015 10:13 am

floyd

floyd
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well that clears that one up. 

cheers rick Wink


__________________________________________________
K100 with lots of K1100 bits - mongrel of a thing...
    

4Back to top Go down   Our EFI systems Empty Re: Our EFI systems Sun Nov 08, 2015 6:01 pm

robmack

robmack
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Kind of like this...but the engine read lines at half this speed. You'll get the idea.


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

5Back to top Go down   Our EFI systems Empty Re: Our EFI systems Sun Nov 08, 2015 6:22 pm

brickrider

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I'm having a hard time understanding what this video is telling me.... Shocked


__________________________________________________
Brickrider
1985 K100RS; brick red, of course!
    

6Back to top Go down   Our EFI systems Empty Re: Our EFI systems Sun Nov 08, 2015 6:48 pm

robmack

robmack
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Thought it underscored Rick's explanation that the valves are probably not allowing any pooling of fuel to occur, given the rate they are operating, as demonstrated in this video of a valve train test setup. Rarely see how valves work at full speed since they're seldom videoed like this.

The other aspect was interesting from the aspect of how impressive the S1000RR engine technology is.


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

7Back to top Go down   Our EFI systems Empty Re: Our EFI systems Sun Nov 08, 2015 7:30 pm

RicK G

RicK G
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The only time I have ever seen fuel pooling be a problem is when I was drag racing.  The cars that were running big V8s (350 cid) or bigger and using carbs like twin 1150 cu ft/min Holleys and at the start line they would be at idle or close after a burnout and then the fuel would pool in the plennums of a tunnel ram manifold.
When the last amber dropped and down goes the foot in would go a shitload of fuel that the engine just couldn't cope with and they would die just after launch, often with an earsplitting backfire and quite often damage resulted that put an end to the days racing for them.
Fuel injection put an end to that.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

8Back to top Go down   Our EFI systems Empty Re: Our EFI systems Mon Nov 09, 2015 1:37 am

indian036

indian036
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Interesting to see the effect of the frame rate as the engine revs up in the early stages. 

It appears that they are opening different amounts or not opening or staying open as the frequency of valve movement matches up with the frequency of image capture. Up at the top end, you don't see the valves opening, but you do see the rotation as they work. 

Bill


__________________________________________________
1985 K100RT  VIN 0028991  My original Very Happy   (Historic rego)
1985 K100RT  VIN 0029036  BOB the Blue Old Bike  (Historic rego)
1990 K100LT  VIN 0190452  Work in progress
1984 K100RT  VIN 0023022  Work needing lots of progress

1986 K100RT  VIN 0090542  Work needing lots and lots of progress
1993 K1100LT  VIN 0183046  Work in progress
1993 K75S  VIN 0213045  Newest toy, slightly non-original
    

9Back to top Go down   Our EFI systems Empty Re: Our EFI systems Mon Nov 09, 2015 5:41 pm

sidecar paul

sidecar paul
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Fascinating, it makes you wonder how engines are so reliable these days with bits doing that for thousands of miles, with an explosion every millisecond!
 I was surprised at the rotational speed of the valves.

Yes, I kind of liked it as well, Rob. Our EFI systems 112350

Paul.


__________________________________________________
'84 K100RS (0014643) (owned since '85), 86 K100RS (0018891) with Martello sidecar (built as an outfit in '88),
'51 Vincent (since '67),'72 Montesa Cota (from new), '87 Honda RS125R NF4 (bought 2015) 
....No CARS never ever!
    

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