another wont idle question

[Boriqua]

I hate to start a new thread but I went through dozens of posts and dont find my exact situation.

Here is where I am (1982 GS750)
New Stator
New Plugs (gapped to .030)
New Dyna coils and ignition
New RR
New battery
New spark plug wires
SPG
Cleaned and rebuilt carbs
New air filter
Adjusted clutch and throttle cable
All my rubber bits are supple and look newish
Valves checked and new gasket installed
Bike runs like a raped ape and is smooth as silk with no funky sounds or odd exhaust gases right up to red line

With all that done I figured I covered "the get me home" details and I set about making sure I covered all potential air leaks. Before this it would idle fine but I never had the airbox bolted to the frame and it was sitting at an angle to the carbs and I wanted to address it. Using spacers I was able to line up the boots to the carbs perfectly and have a tight seal. Double checked with starter fluid.

I put the weather stripping on the cover of the of the filter box
I put a goof plug to seal the nipple at the bottom of the airbox. (When it idled correctly I did not have the weather stripping. I just added it)
I feel like I may have over oiled the filter element so I washed it in some dish detergent and let it dry before reinstalling
I took out the carbs and redid the bench sync. (I havent done a Vac sync yet, tool inbound)
I checked all float bowls and they had gas
If I put my hand over the air filter holes it will surge.
Before I ensured that everything was sealed it idled.

I cant nail the idle now? I get highest rpm at about 3 turns out but then it will surge. I then lower the idle with the adjuster (burning the bejeez out of my hand) and it sounds like and often does stall. I managed to get it where it would idle .. still sounding like it would stall after it warmed up but I could go ride it. It will only idle and still not great after its very warm but I was getting some hanging on deceleration. I would pull up at a light and it would idle for a second or two at 3000 rpm then drop to **** poor idle. I pulled two of the plugs and they look good.

Now I had airfilter oil everywhere before and pooled in the box. Could that have clogged a passage. Am I looking at re-cleaning the carbs.

 

[usmaan88]

Don't know about the airfilter oil clogging a passage but sounds like you have a hanging idle, which would indicate a vacuum leak somewhere in the chain. Have you checked the carb to head boots like you did the air boots?

 

[jlyon40]

Sounds like a vacuum leak. I had idling issues with my 850g then I did what you did with the weather stripping and that fixed my issue I would check the intake boots that's usually where the leak is.

 

[Boriqua]

Thank you for your responses. I dont think its vacuum. I have checked everywhere and early on y restore project I had some vacuum issues and there was a nasty flat spot at around 4000 rpm. This is only affecting idle. The bike runs wonderfully. Its bewildering but I have decided to take the carbs apart again and redip, clean them.
Alex

 

[Nessism]

Do the vacuum sync and see what happens. Good chance it fixes the issue based on what you have done to the bike. I'd set the pilot screws at 2.5 to 3 since you said that gave you the highest idle. Not sure what you mean by surging though. Please explain that comment further.

 

[gearhead13]

Your plug gap is too wide, should be .025-.026. That is the recommended gap with a dyna setup.
When I ran a full dyna setup I tried opening up the gaps and soon found it ran better with smaller gaps.
Greg Cope:
Spark Plug Gaps
When running a Suzuki or Kawasaki with a Dyna-S and high performance coils set plug gap at .026.

 

[Boriqua]

Thank you .. when I put it back together I will regap to the original spec.

New question.. I have been adamant about testing all places for leaks but I just discovered as I was pulling the carbs out to do another cleaning that the hose I bought at Home depot to replace the crankcase breather hose was super loose even with the clamp in place. It could have easily let some air in through on the airbox side. Could this affect performance at idle? Going to replace it next week when it all goes back together but still learning and am curious.