GS 650 barely idling

[Mop Bucket]

Hello
This forum has amzing people and information. I have read a ton of posts and tried a bunch of things. But I am baffled and need the help of the colletive.
I have an 83 GS 650 G that is running like poo. It has an air box with filter and stock exhaust. With the choke almost all the way it will idle, but when I get it to idle it acts like it is going to die at any moment. If I open the choke up more, the RPMs shoot up to 3000ish. If I touch the throttle at all it dies.
The things I are good are as follows. It is getting good spark. I did the coil relay mod per Basscliff site. This is one thing I did before things went bad though. I dipped the carbs because some crap got into them. The valves were adjusted 400ish miles ago. I sprayed WD40 around all the boots and air box junctions. The carb boot o-rings were replaced today. I am running off an external gas tank right now but no difference with the regular tank.
Okay experts and fellow GSers, what should I do or check next? Thanks.

 

[tkent02]

Are you saying it won't idle or run without the choke?

 

[Steve]

With the choke almost all the way it will idle, but when I get it to idle it acts like it is going to die at any moment. If I open the choke up more, the RPMs shoot up to 3000ish. If I touch the throttle at all it dies.

Which way is the 'choke' "almost all the way"?

Which way is the 'choke' "open"?

You have an '83, so your ENRICHMENT control (not "choke") is on the left handgrip. The ENRICHED position is to the LEFT, the RUN position is to the RIGHT.

Please use those points of reference and repeat your symptoms.

.

 

[BassCliff]

Hi,

After you completely disassembled them, dipped them, cleaned them, and reassembled them with a new O-ring kit, did you bench sync the carbs? Have you replaced the intake boots themselves? Is the airbox sealed? You must ensure there are no air intake leaks. Double check the carb reassembly for missing or loose parts.


Thank you for your indulgence,

BassCliff

 

[Mop Bucket]

Are you saying it won't idle or run without the choke?

Correct!

Which way is the 'choke' "almost all the way"?

Which way is the 'choke' "open"?

You have an '83, so your ENRICHMENT control (not "choke") is on the left handgrip. The ENRICHED position is to the LEFT, the RUN position is to the RIGHT.

Please use those points of reference and repeat your symptoms.

Sorry, english is like a second language for me. The enrichment control is pushed to the left. Before, when the bike was running great, all the way to the left would be 4000+ RPM and I never would enrich it that much. About half enriched and a tap of the starter and it was running.

Hi,

After you completely disassembled them, dipped them, cleaned then, and reassembled them with a new O-ring kit, did you bench sync the carbs? Have you replaced the intake boots themselves? Is the airbox sealed? You must ensure there are no air intake leaks. Double check the carb reassembly for missing or loose parts.


Thank you for your indulgence,

BassCliff

Replaced the carb o-rings 400ish miles ago and bench synced the carbs. Double checked the gaps this morning. Intake boots were not changed but still squishy when pinched with fingers. I tore down the carbs to check float level this morning and they looked fine. I pulled a couple of needles to spot check, they looked good. I also checked the holes the vents and gas lines connect too. Thought about pulling all needles based off advice on another thread. :-k

Is the air box sealed, good question BassCliff. Is there something besides spraying WD-40 on it to find a leak?

Hope that helps in finding the issue.

 

[Mop Bucket]

update

update

Building off Basscliff's idea of checking the air box for leaks. I started it up and pulled the air box cover and there was no change. I pulled the filter out and put my hand over the intake hole. The bike surged. I plugged it up about 3/4 and got it to idle. I then could twist the throttle and it would rev up like a good kitty. I let it idle and sprayed start fluid around the different connectors and no change and so I am reasonably confident that there isn't a leak at the boots and seals.

The air box is pretty simple and probably has a good seal. I am wondering if I re-oil the filter if that will be what is needed. I rode through a dust storm awhile back and there were small balls of dirt all over the inside of the air box and on the filter. I wonder if all the oil was sucked out? What you all think? I will go get some oil anyways and reapply.

Will be pulling the carbs too because when I started to rev the bike gas came out the air box drain! So, anything I need to check while I am there let me know.

 

[BassCliff]

Hi,

Have a look at the airbox sealing and air intake repair guides on my little website to get an idea of what it takes to seal up the intake system. Sometimes squirting stuff at it doesn't tell you much. You just have to do it.

Thank you for your indulgence,

BassCliff

 

[chuck hahn]

Big idle knob in the center of the carbs turned in far enough??

 

[1_v8_merc]

Did you check your plugs yet?
They can allow you to rule out things.
(for instance, if the plugs are wet, you're flooding the engine. If the plugs are ultra dried out, you could be getting too much air)

If you give it Throttle and it dies out, HOW does it die out?
Does it sputter out with a "whoooosh" sound?
Does it just die Instantly with No Sputter?

 

[tom203]

Was it running better before dust storm, carb boot orings replacement, or some other operation? At the moment, it sounds lean when you open throttle, but like 1_v-8 _ merc said, check plugs. My 31 year old carb boots are definitely not "squishy"- I'm expecting them to vaporize at any moment until I find a miracle spray-on restorer from Ron Popeil.

 

[Mop Bucket]

Hi,

Have a look at the airbox sealing and air intake repair guides on my little website to get an idea of what it takes to seal up the intake system. Sometimes squirting stuff at it doesn't tell you much. You just have to do it.

Thank you for your indulgence,

BassCliff

BassCliff, you site is amazing and I have had it as a book mark for about a year. I did read the guides. My air box is pretty simple and didn't see much that I could seal. The box cover is over lapping plastic and looks and seems sealed. Not sure what more I could do.

my filter

Big idle knob in the center of the carbs turned in far enough??

That seemed to help Messing with that and maybe the cleaned and freshly oiled oil filter helped? The bike started to run pretty good with the enrichment lever to the right. Confidence was running high, but then, I decided to fix the time gas leak mentioned above before fine tuning the carbs. I pulled the carbs and fixed that issue. I also checked the needles to make sure they were still clean. I had an extra set of o-rings so I replaced the t and gas feed o-rings. Benched synched the carbs again. Put it all back together again and...

Nothing, crank crank crank

Checked spark, yup. Plugs looked dry. Turned the idle screw in and out. Checked the mixture screw and left them at 1 1/2 turns out. Started at 2 and 1/2 turns out. Battery is charging just to make sure it is fine.

Putting the wrenches down and stepping away from the garage.

 

[chuck hahn]

When you drain the carbs you do know you have to set the petcock to PRI for a few seconds to refill them..right? If not it will crank and be very hard to start. The screws may be perfectly set but it still wont want to start unless the carbs are primed. Leave it on prime till it starts then swing down to the ON position.

 

[tom203]

When you replaced the carb boot orings, did you use the robert barr's cycle orings ones or something else?

 

[BigD_83]

BassCliff, you site is amazing and I have had it as a book mark for about a year. I did read the guides. My air box is pretty simple and didn't see much that I could seal. The box cover is over lapping plastic and looks and seems sealed. Not sure what more I could do.

my filter

That seemed to help Messing with that and maybe the cleaned and freshly oiled oil filter helped? The bike started to run pretty good with the enrichment lever to the right. Confidence was running high, but then, I decided to fix the time gas leak mentioned above before fine tuning the carbs. I pulled the carbs and fixed that issue. I also checked the needles to make sure they were still clean. I had an extra set of o-rings so I replaced the t and gas feed o-rings. Benched synched the carbs again. Put it all back together again and...

Nothing, crank crank crank

Checked spark, yup. Plugs looked dry. Turned the idle screw in and out. Checked the mixture screw and left them at 1 1/2 turns out. Started at 2 and 1/2 turns out. Battery is charging just to make sure it is fine.

Putting the wrenches down and stepping away from the garage.

You can throw some rubber or foam window sealer in the groove at the outside edges of the airbox if you want to. It'll make the fit very snug, but it really is the only thing on the 650 airbox that can be sealed further. From what I've seen so far, they are very different from the 850s.

Make sure that the seal between the airbox and the connector to the carbs is tight. If the clamp (should be part #10 in your earlier fiche) is cinched down as far as it goes, you could possibly have a leak there.

As an aside, does your airfilter element load in from the top as shown in that diagram? Or from the side?

 

[Mop Bucket]

When you replaced the carb boot orings, did you use the robert barr's cycle orings ones or something else?

Yeah, they are from Robert Barr.

When you drain the carbs you do know you have to set the petcock to PRI for a few seconds to refill them..right? If not it will crank and be very hard to start. The screws may be perfectly set but it still wont want to start unless the carbs are primed. Leave it on prime till it starts then swing down to the ON position.

I have a temp tank that is like a giant funnel. That is why I am confussed on why it isn't starting. I even double checked the float levels when I had the carbs off.

You can throw some rubber or foam window sealer in the groove at the outside edges of the airbox if you want to. It'll make the fit very snug, but it really is the only thing on the 650 airbox that can be sealed further. From what I've seen so far, they are very different from the 850s.

Make sure that the seal between the airbox and the connector to the carbs is tight. If the clamp (should be part #10 in your earlier fiche) is cinched down as far as it goes, you could possibly have a leak there.

As an aside, does your airfilter element load in from the top as shown in that diagram? Or from the side?

Mine is side loaded, so the diagram is wrong. I will look into a new boot between the airbox and carb connector. I wonder if the new oil on the filter is helping the no start issue. :-k I was so close to riding with you all and so close to bringing a GS back to life.

 

[BassCliff]

Hi,

It's not that the diagram is wrong. The air filter box had to be rotated 90 degrees in the parts fiche illustration so that it could be seen properly. The lid is actually on the right side of the bike, not the top as shown.


Thank you for your indulgence,

BassCliff

 

[Mop Bucket]

Thanks

I will be back at it tomorrow. ray: Guess I will try pulling the filter apart again. Apply some caulking :evil: Pull the carbs again if it still doesn't start. Maybe even try a rubber mallet.

Really at a loss

 

[BigD_83]

Thanks

I will be back at it tomorrow. ray: Guess I will try pulling the filter apart again. Apply some caulking :evil: Pull the carbs again if it still doesn't start. Maybe even try a rubber mallet.

Really at a loss

If you haven't already, check your battery and charge it overnight...you're probably starting to get low if you've been cranking it repeatedly and not getting it to run. Also, make sure the terminals and leads are securely connected. I have gone through the non-starting issue only to discover that my neg lead was loose...enough contact to turn it over, but apparently not enough to get it to turn over and fire strongly. Tightened it down, and away we went.

 

[Mop Bucket]

If you haven't already, check your battery and charge it overnight...you're probably starting to get low if you've been cranking it repeatedly and not getting it to run. Also, make sure the terminals and leads are securely connected. I have gone through the non-starting issue only to discover that me neg lead was loose...enough contact to turn it over, but apparently not enough to get it to turn over and fire strongly. Tightened it down, and away we went.

Thanks big D, I will add it to the list to check. Thats why I love this forum. I think every idea posted in this thread I have investigated. Thanks to each suggestion. If anyone has anything else I will look into it also. I have been thinking of using electrical tape as a way to make sure the connections are sealed on the air box. If that helps I will fork the money out for new boots.

 

[Mop Bucket]

You guys did it! The bike seems to be running great. It was a combo of fixing the needle seats, battery charging, and re-bench synching the carbs with a paper clip. So maybe I have pulled the carbs for the last time in a long time!

But... I put the tank back on to make sure it runs. I also put on a clear gas tube so I can see the gas flowing. No gas flowing with the tube hooked up on prime or on or reserve! If I pull the tube off the petcock gas flows, found out the hard way. Back to searching for the answer. Oh, the petcock is new from z1.