Carb won't stay on the bike!!! UPDATED 3/6 Video (they stay on)

[thousandlegs]

So it sounds like you guys think that I should open the head back up to check valve clearances?  What about the fact that it was running perfect the other day before I took my dog to the vet?  Any ideas as to why it would run so well then do this with no changes?

[jetboy287]

I'm going with fred on this one look at previous post, And I'd check your coil contacts where the wire connects to your coil pack if its not firing start there and work you're way back .

[thousandlegs]

The plug will spark and the coils are connected snugly.  We swapped the coils yesterday to be sure that wasn't the problem and had the same result.  It backfired a few times yesterday and sounded like a high powered rifle.  I think that the valve cover is coming off today or tomorrow to check valve clearances and to be sure that they're all opening and closing as they should.  (insert unbridled cursing here)

[fred]

The plug will spark and the coils are connected snugly.  We swapped the coils yesterday to be sure that wasn't the problem and had the same result.  It backfired a few times yesterday and sounded like a high powered rifle.  I think that the valve cover is coming off today or tomorrow to check valve clearances and to be sure that they're all opening and closing as they should.  (insert unbridled cursing here)

That sounds like a good idea to me.

[bill14224]

I'm with Fred on this.  I'm not trying to convince anyone to do more work than needed, that ain't my style, but carbs don't push themselves off engines, it's the other way around.  Perhaps it ran good briefly because there's a sticky exhaust valve that worked right for a little while, and now it's hanging up again.  Just a theory, but it explains why your carbs frequently jump off the engine!

[thousandlegs]

Yeah, well, I'm going to take the carbs and valve cover off tomorrow and try to make her happy.  Should be in the 70s for the next few days and I wanna get some riding in.  I'm still completely new, at 33, to motorcycling and I've got a bit of a bug from my couple of rides on GusSie.

[thousandlegs]

Alright, today we took the valve cover off and checked all the clearances.  As it turns out one of the exhaust valves, the left one, had no clearance and was likely staying open.  Got all the valves in spec. 

Put everything back together and the bike only ran on one cylinder again. 
Took the carbs apart and gave them a thorough cleaning and put them back on.  Still one cylinder. 
Then we swapped the plugs and found that one of them was dead...it sparked very well but wouldn't do anything under compression.  Got two new plugs and it runs on both cylinders again but there is no throttle response and it idles poorly. 

Anybody wanna buy a motorcycle? 

Not really, but more gremlin help would be appreciated.

[jeremy_nash]

are you sure you reconnected the vacuum line to the left carb? it running lean from a vacuum leak will make your idle all over the place.  been there, done that   

[bill14224]

First I will take a bow for correctly guessing a stuck open left exhaust valve.    I'll think about your present problem and get back later.  Right now I'm thinking carbs, as you keep taking them apart and your symtoms keep changing.

[thousandlegs]

First I will take a bow for correctly guessing a stuck open left exhaust valve. 

Somebody buy that man a beer! 

I am suspect of the carbs too but I don't know what the problem could be.  I took out the 118s and put in 134s so now the jets are 40 and 134...floats are still in spec and I've tried mix screws in .25 turn increments from 1 to 3.5 turns.  The weather is getting nice here in Pensacola and I'm desperate to ride the bike both for fun and for fuel savings.  My other vehicle is a 2000 Jeep Cherokee...fuel consumption ftl!

[The Buddha]

118, 134, you're screwed, you have DJ.
I suggest you replace the ^&*)(*&(%^ with the other provided ()*(&&*(O and maybe adjust the ^%^% to (*&()( and when you start it, just jiggle the (*&*)( and pray that the ()*(*&^*( does not come off from the $#^%#$ as it did before.

You have stock needles still or you toss them ?
If you have stock needles sitting around, tell me what setup you have and I could see if I can guide you.
BTW starting this weekend I'll have a running GS (after almost 3 years), I can set and tune the DJ crap to your setup. That will possibly help scores of others ... but I cant guarantee it will work. I also will charge ya, possibly 75 bucks or so. And return shipping. However if I get it working on mine you should have no trouble on yours. Unless the problem is elsewhere.
Cool.
Buddha.

[thousandlegs]

To the best of my knowledge the needles are stock.  All I have changed is the main jets which, as I said, are now 134s.  On the top end of the carbs I have one washer and the clip that is on the notches is on the top notch so:
plastic ring>washer>clip on top notch all inserted and connected to the diaphragm which was inspected and has no holes or tears
timing is set properly, valves are in spec, float heights are correct (even with the top of the float bowl) according to the tube method

Did you use symbols on purpose here: I suggest you replace the ^&*)(*&(%^ with the other provided ()*(&&*(O and maybe adjust the ^%^% to (*&()( and when you start it, just jiggle the (*&*)( and pray that the ()*(*&^*( does not come off from the $#^%#$ as it did before.

[The Buddha]

Then forget 134 and 118 and whatever.
Stock needles, and your pipe and filter ?
Anyway stock filter with or without pipe = 125 mains, 40- pilots 1 wahser under the E clip in the needle and 3 turns.
K&N in airbox and pipe = 127. mains.
K&N lunch box with pipe 150 mains.
That's cool.
DJ uses some funky crap you cannot buy anywhere, so I used the %^%%$ notation.
No DJ = No problem.
Know DJ = Know problems. You know, like Jesus.
Cool.
Buddha.

[bill14224]

Hey Buddha!  What size washer, and can I get a pair of 127 mains?

[thousandlegs]

Ok, here's a video of it doing what it's doing.  I have 118, 128 and 134 jets.  I put the 118s back in because it ran so well the other day with them in.  I tried 1.5 to 3 turns at .5 turn increments.

http://www.youtube.com/watch?v=gyyXiYp4Nwc

Thanks!

[bill14224]

It sounds like the mixture screws aren't set right, and/or the choke isn't working properly.  I don't know the temperature where you are, so it's tough to guess.  When you're just trying to get it started and not riding it, it doesn't matter what main jet size you have.  It's the pilot circuit and choke we're concerned about at this point.  Make sure your choke is working properly.  WD-40 both ends of the cable, and also the choke plunger.  Make sure it's free to move all the way in and out.  Set the air and fuel screws to the factory settings.  That should be close enough to get it running.  For now, don't stray far from stock settings, and set the choke where you normally would under those conditions after you make sure its total movement is free.  We know those are close enough for it to run.  If it still won't run, there's something else going on.

[thousandlegs]

I've had the mix screws at several different settings.  The choke...I can see it doing it's thing when I've got the carbs apart but does it do anything aside from open up that small hole inside (forgot if it's in the top or bottom) where you can see it?

Still at a loss and I can't afford to send it to Buddha as my wife and I have both recently been laid off. 

[thousandlegs]

Another update for those who are trying to help me figure out my problems.  I did a compression test today:
Left 122
Right 135

[wladziu]

Maybe the exhaust from the other cylinder was coming into the left side through the open valve, popping off the carbs.  Fixing this with resetting valve clearance (if that is the problem) could have fixed the "vivacious" carb issue, but it might run rough if someone has screwed with the timing to make up for valve work.  Not sure if it's possible, but just an idea.  Maybe the new plugs with better corners on the electrodes could be masking the issue, since they offer a stronger/longer lasting spark.   

I 'm obviously not very good at this, so don't laugh too hard. 
But, when I hear backfiring then I think timing or flooding. 
If this is a new problem, could it be that someone tried the timing advance mod and screwed it up?  And that it's evident now that you adjusted the valves? 

Is it possible that the maladjusted valve accumulated carbon and is now not providing a proper outlet when open, due to the tighter clearance?  Probably not, but just a thought. 

Have you tried with the tank on, now that you've done all of this wrenching?  Maybe that little funnel isn't giving enough pressure to fill the bowls.  Probably not this one, either. 

Head gasket could have screwed up on the left side.   

Could have the valves set too tight?  I haven't adjusted mine yet, so don't yell at me if this isn't possible.  Just shooting around some ideas.  Interesting problem you have. 

[Suzuki Stevo]

You pulled the head, you had to have touched the cam timing to do so. Without reading through 3 pages, I'm with ohgood on the 3rd post....cam timing.