running really rough and stalling

[unicorncomputer]

Just got the bike running for the season, took it out for the first ride. It was running a little rough in low rpms, but I figured it was just gettting cleaned out. I put some seafoam in, changed plugs and battery. It is getting worse. it is running rough even up around the 3-5k rpm now and will stall if I let it come to an idle. Do I need to pull the carbs and clean them?

I pulled the air filter, it looks fine.

not sure what to try next.

Thank you,

Steve

[natemoen]

Do I need to pull the carbs and clean them?

That would be the place to start if it was running good when you parked it last fall.

[BA80]

Pay most particular attention to cleaning the pilot jets, pilot circuit and idle circuit.

[unicorncomputer]

I know what the pilot jet is, but what is the pilot circuit and idle circuit?

Thank you,

Steve

[BA80]

Those are the passages. Those 2 circuits are actually part of the same circuit if that makes any sense. They control fuel and airflow from idle on up to about 1/2 throttle.

Here's a kind of a crash course on the operation of these carbs. Read the text don't just look at the pictures.

http://home.everestkc.net/malsin/Motorcycle/carb/mc_carb_theory_101.htm

http://www.iwt.com.au/mikunicarb.htm

[motoman]

Parked for some time, liklihood of a mini science project inside carbs is pretty good. When U remove pilot jets and emulsion tubes, use a magnifying glass under good light to look down inside/thru pilot jets and emulsion tubes. Be surprised, magnified, what you'll see. Clean all air-bleed side holes on both these components with a toothpic......no metal. Make sure teeny hole in bottom of pilot jet is cleared. Just went thru all this on my Venturer leaving it set in corner of man-cave with bike cover on it for a year since I was riding my other STeed......lesson learned, and not sure if Star-Tron or any other stabilizer would of helped retard that from happening.

[unicorncomputer]

Just pulled them off, haven't torn them down yet. Headed out to get some cleaner.

Really surprised, put in seafoam and ran for 10 minutes, put carb stabil before storing and empting carbs.

will see what happens.

[MPittma100]

Ethanol

Just pulled them off, haven't torn them down yet. Headed out to get some cleaner.

Really surprised, put in seafoam and ran for 10 minutes, put carb stabil before storing and empting carbs.

will see what happens.

You can thank the ethanol that is in our gas for your current problem. Next time it is going to be stored, you should leave non-ethanol gas in the fuel system. If it is not available to you, you are better off draining the entire fuel system - tank, carbs, and lines. Seafoam nor Stabil are effective (enough) to combat the ill effects of ethanol.

mike

[BA80]

I will go out and start my bike every week or 2 when it's to cold to ride and let it run for 15 or 20 minutes just to avoid this problem. I haven't had to take the carbs off of mine in 3 years.

[unicorncomputer]

Gets too cold here even to get it to start it in Vermont.

Sure enough, there was crap in the bowls.

Something I noticed, the tube that the main jet screws into on carb 1 and 4 has 4 sets of holes cross drilled while carbs 2 and 3 have 2 and 3 sets cross drilled.

Is this correct? Supposed to be this way?

As always thank you all for you assistance.

I will try and find somewhere that has ethonal free gas.

I will go out and start my bike every week or 2 when it's to cold to ride and let it run for 15 or 20 minutes just to avoid this problem. I haven't had to take the carbs off of mine in 3 years.

[BA80]

Yes, the emulsion tubes with fewer air bleed holes go in carbs 3 & 4. The 2 center cylinders need more fuel to help cool them because they get less airflow.

[unicorncomputer]

Do you mean the emulsion tubes with fewer holes do go to 2 and 3(inner cylinders)?

[BA80]

YES! That's what I meant.