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I'll do my best to explain how this system functions. First, any dimension of valve cable is spec'd assuming the cable is straight, not curved between the cylinders or wrapped around anything else. And yes, the F-7 cable dimension of 36mm ends up with almost no adjustment left. Because of tolerances, mayby you can't even get to 36mm. Were working on that. But the critical point is that both cables are the same, even if there up to 1mm short. I'll try to explain as best I can why that length is not as critical as you think.

Imagine the face of a clock as the servo wheel. Now imagine that the numbers of the clock face are voltages. we'll say 12:00 is 1 volt, and 6:00 is 7volts just as an example. Now imagine that the distance between 1 volt and 6 volts is the low and high tolerance range of the servo motors rotation operation. This value is established by us. That rotation distance would represent a cable/valve pull of mayby 25mm. But the actual stroke of the exhaust valve is only 10-12mm. What that would mean in our clock face example is this.

The actual stroke required to function the valves correctly would be something like 2 volts (1:00) to 4 volts (3:00) or lets say the cables were out of adjustment and were too long. Now the stroke is the same, but the new voltage values (position) is something like 4volts(3:00) to 6volts(5:00). Both setting still function exactly the same because you havn't gone less than the 1volt minumum, or exceeded the 7 volt maximum. If you did, the servo would cylce 3 times and stop, indicating a failure.

The servo always pulls to the maximum valve open as long as it hasn't exceeded the voltage range. It then tells itself to remember that voltage as the maximum distance. Then it knows exactly how far down the valve needs to go to be closed, because we have programed that distance value in the CDI. So if adjustment is off, if cables stretch, or something else, It always goes full pull, then comes back a predetermined distance. Everytime you restart your sled, it rechecks itself for this adjustment. Some reset at low RPM, some reset at higher RPM, but they all do at some RPM, once each time you restart the engine. I hope this helps you understand the system function.
 

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So if adjustment is off, if cables stretch, or something else, It always goes full pull, then comes back a predetermined distance.

I know I've read here where others have had their cables come right off the servo wheel, and I've had the same problem. (Sled would tach out at 8000 vs normal 8500) It was assumed that this is because fo 1 of 2 things. Cables too long or out of adjustment. Both of these could not be the cause, based on your explaination.
Would you have any idea what then may have caused the cables to fall off the servo wheel?
 

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The cables fall off for these reasons..The return action of the cable due to spring not pulling hard enough, gummed up valves or I think #1 thing, cables are sticky.
 

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Why would the cables be stickey?, And how could I check that?
I did pull the valves out and cleaned them, they were terrible. But with only 700 miles on it, I assumed that the valves were gummed up because the cable had fallen off the wheel and they stayed closed except during extreme accelleration. By being closed, I thought the oil would accuulate on the valves.
Thanks for your help.
Garry
 

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only way to tell..Is to disconnect the cables and see how free they move.. Well, snow, water etc. can rust them up..
 
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