Carbs won't sync. pops spits gas back into the synchronizer

[Troutdog]

1981 GS850G. The bike was running fine till it sat up for about 10 month's. I cleaned the carbs,,tried to break loose the A/F idle screws, but they stripped.When running it pops there is a blue flame in the left pipe and when it hiccups it shoots white smoke"or something"out the #1 and/or #2 carb intake boots.Someone told me to sync the carbs. I finally got my synchronizer. I did everything by the book. It won't adjust,,,the mercury in all four moves rapidly up and down about an inch,,, there all low and different and very hard if even possible to adjust. The 1 and 2 carbs shooting a little gas back into the sync everytime it hiccups. Please help Thank you, Joey

[Macmatic]

Do you need to put dampers in the lines between the test ports and the gauge? My CarbTune II calls for about 4in of vacuum tube then a 1in section of very small inside diamerter tube and then about a yard of vacuum hose again. The smaller tube has an ID of about 1mm or less.

The small tube is to "dampen out" the pulsations and the instructions say you'll have problems like the ones you describe with levels all over the place if you don't do this. Don't know if that has anything to do with your other problems but if you don't have dampers they might help you get things leveled out.

Try bench synching too if you haven't. Do you have the whole intake system togethe, airbox, filter and lid?

/\/\ac

[kiwijetpilot]

it sounds as though there is something else going on here... when you say it spits "white smoke or something" out of the intakes, do you mean back through the carbs when the engine is running, or trying to run? That "white smoke" is probably fuel mist. The blue flame will be unburnt fuel igniting in the pipe, and that can be caused by having a float stuck down and one of the carbs dumping a lot of raw fuel into the pipe. If the engine is backfiring you may have an air leak somewhere, are you sure that none of your intake boots are leaking? Maybe the rubber has perished with time. Have you checked out your ignition? A bit of corrosion on some vital connections will play havoc with your attempts to tune the carbs. For that matter, what do your plugs look like? Are they fouled at all?

Just a few things to check...

[Troutdog]

thanks for the tips

first Macmatic you said to dampen out the pulses with a tube,,,,that rings a bell my syncs came with white cap looking things that have about a 1mm hole in the center,,I never could find where they go,,,where do they go? do ya'll think the 4 or 5 drops of gas that went into the mercury reservoir will hurt. I opened the hole thinking it would evaporate,,,,,
kiwijetpilot I think it is fuel mist and yes back though the carbs,,, awhile ago I had a few bad intake leaks I can't afford new ones so I tried to fix the cracks with silicon don't laugh I'm poor,,It worked for a while maybe there leaking again...I checked the floats there up to spec.I have had electrical problems,,It won't crank until I turn the handle bars to the right...
The #1&2 spark plugs are new,,but very wet with gas. Very hard to keep running when cold then it warms up runs a little better.I love my GS Thanks for all your help,,,,Joey

[Macmatic]

Re: thanks for the tips

first Macmatic you said to dampen out the pulses with a tube,,,,that rings a bell my syncs came with white cap looking things that have about a 1mm hole in the center,,I never could find where they go,,,where do they go? do ya'll think the 4 or 5 drops of gas that went into the mercury reservoir will hurt. I opened the hole thinking it would evaporate,,,,,

No clue where they would go on your setup. On mine you have to cut off a couple inches of each hose on the engine end and insert an inch long section of the 'damper" hose where you made the cut.

What brand of synch tool do you have? Maybe someone here has one or the docs might be online someplace as a .pdf.

I think any gas should come to the top of the mercury and evaporate off overnight but be REALLY careful with that stuff. I'm a tightwad, penny pinching, change rolling SOB and I spent $100 on a CarbTune II just so I wouldn't have to mess with that stuff.

Good luck, keep up posted.
/\/\ac

[duaneage]

Pick up the idle speed to 1700 RPM , that should smooth out the pulses. Insert the restrictions into each tube before installing the tubes onto the glass rods. Shove them equally in about an inch, keep them the same. make sure all of your clear tubes are the same length as well.

[kiwijetpilot]

Joey, have you changed ANYTHING between the time it last ran properly and now? It sounds a lot like you have ignition issues to me, in addition to any fuel issues you may have.

If it were me, I would check every connection in the ignition system, and maybe try testing the coils and spark plug wires as well. If your ignition system is not up to spec, it will be very hard to set your carbs up. Your plugs may be intermittent if they are soaked in fuel, your spark plug caps may be loose, and so on.

If your bike was running fine the last time you used it, it is unlikely that any settings have moved since then, the most likely problem is that dried-out fuel has gummed up some of the smaller passages. How did you clean them out?

I still think you have major air leaks somewhere... if you can get it running, try squirting a little engine starter fluid around your carb boots... if your engine suddenly gains rpm, you know you have a leak.