Little Throttle response at idle, stalls

[Guest]

I have been fighting with a running issue on my 82' 550L. It starts right up when cold but has no throttle response if I blip the throttle it will rev a bit but well after I close the throttle. If i put my hand over the intake it revs no problem but only revs to 4000. if i let it warm up a bit the throttle gets more responsive, above idle its fine. after the bike warms up completely it seems to stall and not restart.

if i let the bike sit for even just a minute it will fire right up.

What could it be? carbs?

oh yeah here is what i have done:

-cleaned carbs, separated and soaked.

-new intake orings

new boot since one had a hole.

-dyna s ignition, timed like it should be.

-I did adjust the valves as well.

Honestly could my issue be a tight valve? I sprayed around the carbs with carb clean and i got no response.

Thanks

[Steve]

It starts right up when cold but has no throttle response if I blip the throttle it will rev a bit but well after I close the throttle. If i put my hand over the intake it revs no problem but only revs to 4000.

Let me take a wild guess here, you have no airbox or pods on the carb intakes. Right?

Put the airbox back on and report back.

.

[tom203]

Assuming the" hand over the intake stuff" means you remove filter element and block airbox throat, my bigger concern would be
"after the bike warms up completely it seems to stall and not restart."
Does it restart after a few minutes? Next time it behaves like this, take 2 plugs out right away and inspect for fuel (before it can evaporate).Sounds fuel related since you have spark.

[curtie94]

I do have the air box installed. I was just putting my hand in front of the intake on the lid.

Yes the bike will restart after a couple minutes. I'll check the plugs when it stalls and see what they look like.

Are you thinking that it is too rich?

[curtie94]

I checked the mixture screws and I had them at 3 1/2 turns out for some reason, i turned them out to 2 1/2 turns and it isn't stalling anymore. When the bike is cold it has no throttle response at idle still but once it warmed up it was fine.

I took the bike for a ride and I noticed below 3000 rpms It has a nice bog then it takes off above 3000.

I checked the plugs when I got home and 3 of the plugs where dark brown and cylinder #1 was a whitish color so it seems like I have one lean cylinder and that explains the bog and the hanging idle.

[curtie94]

The bike is still doing the same thing where it won't start but even if I just shut if off.

If I let it sit for a while it will restart but otherwise it won't. I checked the plugs and 3 of them look rich while one is bone white. I stayed carb clean around the carb and it didn't affect it at all. The plug was white at idle and after riding.

[curtie94]

I was looking at parts diagrams for the air box and noticed what they call a ring. Here is the parts diagram:http://www.suzukipartshouse.com/oemp...a7/air-cleaner

It is number 11.

I am only wondering because I do not have these and I'm lean on one cylinder. Would that cause it? What exactly are they?

I think that I will pull the carbs and make sure that the air boot and o-ring are fine. Only because I soaked the air boot on that carb with starting fluid and the rpms did skyrocket. but it took a little while before it did.

Is there anything else that would cause that carb to go lean like it is? I did pull the carb drain and it was full. If the float was set to lean would that be my cause? Or does it seem more like a air leak?

[tom203]

Maybe part #11 is on outer carbs is to prevent the clamp from collapsing the the rubber boot, but I don't know.
since you're pulling carbs, check float heights and before reinstalling carbs, set rack up in vice (oriented like how they sit on bike) supply fuel to rack with temporary fuel supply and make sure the fuel needle/seats can hold back fuel for ten minutes at least.
this "shutting off stuff when warm" suggests a rich mixture to me on all but #1

[Steve]

I would like to go back to the original post and ask a couple of questions.

oh yeah here is what i have done:

-cleaned carbs, separated and soaked.

Did your "separated and soaked" include new o-rings?

Did the procedure you followed resemble THIS ONE?

I did adjust the valves as well.

Honestly could my issue be a tight valve?

If it is, at least you know who did the last valve adjustment, and when.

.

[curtie94]

How will I know if the needle and seat can hold back fuel. Will it start to come out of the mouth of the carb?

Yes I installed new o rings. And that is the exact walk through I followed.

[Steve]

How will I know if the needle and seat can hold back fuel. Will it start to come out of the mouth of the carb?

Yep. . . . . . .

.

[curtie94]

I just tried what you said about putting the carbs in a vise and with the external fuel source. I let it sit for 20 minutes and the fuel level never changed in my funnel. So the needle and seats are fine. But I wonder if I have a blockage in Cyl 1 carb needle and seat.

Ill check float height and go from there.

[curtie94]

I looked over the air boot really well and I noticed a tiny pin hole so that explains the air leak.

I checked the float levels and they seem fine. Maybe after I fix the air leak I well be able to set the fuel screws and fix the plug fouling.

[curtie94]

I got a new boot installed and it seems to run a little better but more or less the same. still cylinder 1 is lean and the rest are rich.

I noticed that when I sprayed carb clean around cylinder 1 it would raise the idle but then I noticed I was spraying around the carb vent so that may have been why the rpms raised a bit.

I took it for a quick toot around the block and noticed the rpms hang quite a bit.

What would you set your mixture screws at to start to start? I think right now i have mine set at 2 1/2 turn out. I didn't have much time to play with the bike today, I took the carbs out checked the pilot curcuit of cylinder 1 carb and checked the float heights of all the carbs and they are all good. right in spec.

Needle and seats are new and seem to be working well.

Is there anything else I could check?

I have tomorrow off so I will hopefully get the bike going well then.

Thanks

[curtie94]

I didn't have too much time to run the bike today, but It hasn't changed, when it is cold it barely runs it will start with choke, if I shut the choke at all it will stall. It also has no throttle resonse.

Once it warms up a bit I start to get throttle response but it is still barley there.

Could it be a leaky air box? Im really getting fed up with this bike. Nothing I do fixes it. 3 Cyls are rich and 1 is still lean.

After it warmed up I tried playing with the fuel screws and the idle didn't change at all.

It is still doing the same thing when it stalls and it won't re start