Put to bed fine, now won't run without choke

[240punk]

Just pull the carbs real quick and blow them out. Gotta be it.

[GsRocket]

J C,
This is on you 1980 GS1100 right? It definately sounds like a fuel flow issue/ possible air leak and your plugs look pretty lean

When was the last time you checked you manifold O-rings/ have they ever been changed? If you do take your carbs off make sure to check them its only a few extra screws and it could save you a huge headache chasing carb/jet problems.

Second would be how does your fuel flow from your petcock look. i would compare prime, reserve, and ON to make sure everything is flowing right. Sometimes it just needs to be blown out with some compressed air, i have to do mine about every 6 months.

If both of those are fine then dig into you carbs and make sure floats are working fine and jets are not blocked.

[J_C]

J C,
This is on you 1980 GS1100 right? It definately sounds like a fuel flow issue/ possible air leak and your plugs look pretty lean

Yeah this is the bike. It does seem lean, doesn't it, considering that was after running on choke.

When was the last time you checked you manifold O-rings/ have they ever been changed? If you do take your carbs off make sure to check them its only a few extra screws and it could save you a huge headache chasing carb/jet problems.

Are you referring to the exhaust gaskets? Those were replaced a few years ago, but pipes have not been removed and I've only put about 1500 miles on it since then.

If you're talking about another set of rings between the carbs and the boots, I don't think my model has those.

Second would be how does your fuel flow from your petcock look. i would compare prime, reserve, and ON to make sure everything is flowing right. Sometimes it just needs to be blown out with some compressed air, i have to do mine about every 6 months.

If both of those are fine then dig into you carbs and make sure floats are working fine and jets are not blocked.

I ran it on both prime and run (those are my only two settings, no reserve) and it didn't make a difference. I can also see the fuel flowing through my clear fuel filter, so I don't think that's the problem. Especially because I can get it up to 6-7k rpms on choke. It's just the instant throttle is applied or the choke is lowered that it dies.

I, having cleaned and redipped these carbs probably 10 times since I've owned it as the result of a now fixed rusty tank, hate working on the carbs. But I think that may be what I have to do. I'm just especially surprised that there may be some blockage because I did put sea foam in the gasoline 2 months ago, and then ran it several minutes to make sure that it got to the bowls. Further, I've not heard of sea foam causing idle problems before, and I've accidentally added way too much in the past and know the funny smell it causes when you use too much. Ugh.

Anyway, thank you for all of your comments!

[KEITH KRAUSE]

Sounds like clogged jetting or lack of fuel to the jets, other than the starting circuit (choke).
You should drain and compare/save the fuel in each bowl. Be sure the quantity of fuel is correct and all four are similar in quantity. You mentioned planning to do this. Very easy to check and then you'll know if the problem is fuel related that correct fuel quantity/level is available to the jets. If so, then it would seem that your jets aren't passing fuel correctly. But it seems funny that your pilot jets and main jets could clog up at the same time, and, clog up in only 6 weeks since you rode it around with no such problems.
Pilot jets are smaller and can clog easily but mains take more time to clog from old gas, unless something in the fuel plugs them up. If only your pilot jets were clogged then any throttle opening wider than 1/4 would then transfer vacuum to the main circuit and draw fuel through the mains.
So if you have fuel in the bowls it would seem both pilot and main jets are clogged. I would suspect debris in the fuel for it to happen as you say, unless there are any other details you haven't mentioned. The above is pretty easy to check, even if you have fuel and need to remove the jets you can do that with the bowls removed only. Short screwdriver is all.
Electrical issues can mimic fuel issues too. If you don't have proper voltages at all rpm's then the bike won't accept throttle either. Weak spark can combust smaller ratios of fuel at several thousand rpm provided by the starter circuit but open the throttle and a weak spark can't combust a full fuel flow and it will just gag/stall the bike if you force it.
The bike has sat 2 years, then ridden just once. Electrical issues can sometimes seem odd and not make sense. An electrical system doing nothing then "shocked" after 2 years can do funny things to the battery, ignitor and voltage reg/rec. As part of basic maint' you should read the charging info at this site or your manual and do a test of your R/R and battery first. If the R/R sends out proper voltage at all test rpm's and the battery truly holds a PROPER charge, then the electrical is probably OK. I'm not sure about testing your ignitor and though I don't know much about them, I don't think this sounds like an ignitor issue. Just be positive you have CLEAN/SOLID connections throughout the harness before testing. I know it sounds like a hassle but you know what we say around here...check the basics first. A simple multi-meter will show you voltages and resistance. I'd probably start with the electrical check if you're able. Should be done anyway. Hardest part may be checking all the connections. If all is good, then you know something is up with the fuel filling the bowls or the jets.
PS: Just had this thought to add... float needle valves can easily "stick" with just a little gum from the gas. I never had all four stick at once but if stuck then no fuel or very slow fuel enters the bowls. "Slow" entering fuel can trick you because the bowls may look full upon removal but if the fuel filling the bowl can't keep up with the fuel being drawn out by the jetting then you'll have major fuel starvation. So check them too if you inspect with the bowls off. Put a rag or bowl down first then turn to prime and crank the motor to open up the petcock. Fuel should flow readily at all four valves. I believe your petcock type requires actual cranking to supply vacuum to make the petcock flow fuel. Just putting it on prime isn't enough. So says the factory manual I have for the '80 GS1000. If I'm wrong then disregard that.

[J_C]

Keith,

This is tremendously helpful advice. Thank you. I agree with you that it seems odd for everything to suddenly go to pot at the same time.

I am definitely going to run down your list of things to check. You've really gotten me thinking though... The battery was new, and I was checking it every few days via my mounted battery meter, and all of a sudden I checked after a week and it was down to 9 volts. I figured I had let it go too long without starting and threw it on the tender. I'm going to take it off tender, let it sit a few days, check it again and do a load test. That would certainly make sense.

Of course, I will check the fuel levels and everything else as well, including the harness. I became well acquainted with it after going through and recrimping most the connections a few years back.

With all this advice, I certainly ought to be able to track down the culprit. Thanks again, and good hearing from you. Maybe I'll see you on another ride one of these days!

[chef1366]

My L went to heaven.

[salty_monk]

Take it there is nothing clogging the exhaust pipes (birds nest, water from where you washed it?)

Had something quite similar on my 750 but it was water in the exhaust stuck at the collector... poor engine couldn't exhale!

If voltages check out then I'm with Ed, if you can nurse it out on the road with a bunch of seafoam in it then it will clear...

Gas these days goes off fast (and don't forget the garage might have had it in their tank a month or so as well...)

Good luck with it. We should go for a ride!

[1948man]

My L went to heaven.

Fitting place for a Bat out of Hell.

[1_v8_merc]

The gasoline today is junk, 1 or 2 weeks and its already going bad!
Gas stabilizer is your friend, use it!
(even with that it won't hold for too-too long)

[Steve]

My L went to heaven.

But ... I thought I heard that it made the trip in a handbasket.

.