Dellorto blues, I've reached my limit Options

[barefoot]

For several years after After I but it all back together the car's been running fine, had to clean one carb once and that worked fine. Now it's getting worse won't idle, it just dies after I let off the throttle. Runs strong at higher loads but very poor at idle & low load. I've cleaned the carbs enough that think I could do it blindfolded. I know the points dwell is OK and I haven't touched the advance. Using a heat gun i can measure header pipe temps just before muffler and one cylinder on each bank is way lower temperature than it's neighbor after holding the rpm's just above idle speed.
Think I'll pull the carbs off and do a compression check just to rule out one thing.
Can't even do a synchronize without a smooth idle.
Is there someone in our group who is Dell 40 expert so i can send carbs off to ???
I've prided myself as a competent mechanic but this has got me on the edge.
Not having fun anymore (IMG:style_emoticons/default/headbang.gif)

Barefoot

[cgnj]

@Barefoot I am a Dellorto fanboy. Here are my questions. What type of sync tool are you using snail or unisync? Do you have a center pull linkage, cable linkage, or a hexbar or similar? post pics of the linkage to the throttle lever.

What Is your idle speed and is it stable? If you idle is stable, pull you plug a plug wire and make sure the idle drops. replace it and then test each cylinder. Let us know. At stable idle, are all of the carb throats Kg/hour of air the same? How many air bypass screws are fully seated? When were the valves last adjusted? Do you know what cam is in the car?

[barefoot]

@Barefoot I am a Dellorto fanboy. Here are my questions. What type of sync tool are you using snail or unisync? Do you have a center pull linkage, cable linkage, or a hexbar or similar? post pics of the linkage to the throttle lever.

What Is your idle speed and is it stable? If you idle is stable, pull you plug a plug wire and make sure the idle drops. replace it and then test each cylinder. Let us know. At stable idle, are all of the carb throats Kg/hour of air the same? How many air bypass screws are fully seated? When were the valves last adjusted? Do you know what cam is in the car?

My idle speed isn't stable I have to keep slight throttle pressure to kept running, thats my big problem, so i can't attempt a sync (snail) I know air bypass screws are set properly and hex bar linkage, but know it's set evenly. i know o-rings on idle mixture screws are intact and are set to same turns as when it ran well. it has a WEB 494 cam and I just recently adjusted valves for it's 3000 mile check-up.