1981 650 gs running like crap

[stingger]

i have posted in the elctricle area and also checked the carbs. the two left plugs are black (other two on right r white). its back firing from the exhaust but the left exhaust is pooring out a white rich gas smoke. it was running fine for the past few months and then this happen on the way home the other day. any ideas?

[Octain]

Have ya cleaned the carbs yet?

[stingger]

i replaced the flot valve seals and cleaned the jeta even the ones that the needale valves slid into. ( i did not remove the carbs from their inline rack ) i checked to see if the points was bad but i seen that it is CDI. at idale it runs ok but thats it. when i ride it it rund but like its runing on two cylinders.

[Big T]

i i checked to see if the points was bad but i seen that it is CDI. at idale it runs ok but thats it. when i ride it it rund but like its runing on two cylinders.

Maybe it is running on 2

Did you check?

[Octain]

Sounds like classic symptoms of a bike that could use a thorough carb cleaning.

[stingger]

yes i checked the if the was firing ( the old fashion way by haven one of my older boys hold the plug wire while i cranked it lol sorry) but have not put a meter on it. its like it cuts out on two of them take off is ok but at about 15 to 25 mph is when it starts doing it or if i hit the gas at ideal

[duaneage]

Check the connectors on the coils, maybe one came loose. They are 1/4 inch spade terminals and not very tight, I don't think it's carbs, happened too suddenly. check the pickup coils with a voltmeter, the green wire to the engine case resistance should be the same as the blue wire to the engine case resistance, I think it's 130 ohms.

There are other tricks you can do to troubleshoot this, look at these first.

[stingger]

ok ill check that out and get back with ya thinks

[tom203]

Check the connectors on the coils, maybe one came loose. They are 1/4 inch spade terminals and not very tight, I don't think it's carbs, happened too suddenly. check the pickup coils with a voltmeter, the green wire to the engine case resistance should be the same as the blue wire to the engine case resistance, I think it's 130 ohms.

There are other tricks you can do to troubleshoot this, look at these first.

On this model the two pickup coils are in series, so if one goes, there should be no spark whatsoever so no idle, no smoke ! as far as I can tell. Disconnected from ignitor, the blue to green wires should show about 300 ohms.Stingger needs to determine which cylinders aren't firing off idle.

[stingger]

Found it lol. I found that the number two plug was getting gased out and it wasn't from the carb. From what i can see the vacum line that runs from the petcock to the intake boot between the head and carb is sucking gas straght into the cylinder. Is this right or is it not supost to suck gas?

[Big T]

no, not supposed to be gas in the vacuum line

You need a new petcock

[stingger]

when i unhooked it and pluged the line it ran alot better untill it couldnt get gas lol. is there a rebuild kit for it?

[Charlie G]

when i unhooked it and pluged the line it ran alot better untill it couldnt get gas lol. is there a rebuild kit for it?

The best thing to do is get a new one. The rebuild kits have a reputation of being unrliable. The isn't that much money to be saved. I think Z1 has them.

http://www.z1enterprises.com/detail.aspx?ID=1715

cg

[stingger]

ok thanks and thanks for the help from everyone

[duaneage]

It's usually the simple things that cause these problems. My bike had a clear vacuum line for the petcock that let you see if it was taking gas through it.