%Pilot jet use at cruise

[Guest]

Hi,
I have 1 cylinder that is fouling/missing on my GS850L. My uncle did a quick strip and dip, but honestly it is as if he never touched it.
Anyways I was wondering when a GS850L is in 5th @ 55mph is the pilot jet just a small portion of the fuel being used or a much higher percentage than full throttle?

Thank you

[mmattockx]

It is the throttle opening that determines what circuit you are on. How much is your throttle open? When I was jetting my 1100E I put tape on the throttle housing and marked the throttle travel in increments of 1/8 of full travel. Then I could look and see if I was at 1/8, 1/4, or whatever and could tell which circuit I was running on.


Mark

[Mr.Mom]

Hi,
I went for several rides today. Each one I was well within 1/4 throttle more like 1/8th. There seems to be one cylinder that gets a black sooty coat no matter where I have the mixture screw. The other 3 are ~ 3 1/2 turns from bottom. Each ride I took I lowered the rich looking cylinder mixture screw. Even at 1/2 turn the plug is still getting that flat black sooty look all over. The missing did seem to get worse as I lowered the a/f screw.
Can a plug appear to be "rich" from not firing all the time due to electrical problems? Or perhaps it is rich as the plug color suggests...?

[ShadowFocus603]

Pull the carbs and do a full proper dip/sonic clean with new o-rings. A 'quick strip and dip' will not cut it on these old Suzuki's. I just fired my 850 up for the first time tonight in who knows how many years and all it took was 2 hours per carb in a sonic cleaner with new o-rings and resealing the airbox (which you may want to look into as well). Also plug color doesn't mean diddly unless you are doing a chop at different throttle openings. Just looking at them after a ride tells you nothing.

[Mr.Mom]

I am assuming there shouldn't be gas in the vacuum line to the gas tank...?

[tkent02]

Nope .

[Mr.Mom]

If the diaphragm had a small leak, could the gas leak into the vacuum line causing that carb to be rich?

[tkent02]

Yep .

[Mr.Mom]

Thanks folks for the ideas. The petcock was leaking gas into the vacuum line causing massive plug fouling. I simply plugged the line and ran the valve on prime. Now the bike runs smoothly at any throttle position. Ordered a new petcock also.

Cheers!
Andy:
Wisconsin