Can't get any better than this...Vacuum values problems

do you guys push them with so much force, the ones in front? This is what I do, but maybe they just need to be seated without forcing? Because for the rear ones I just push them and use a flat screwdriver like a shoehorn, but not as vigorously as I do with the front ones

 

its important to get dlown low with a flashlight to check that the front carbs are fully seated.

 

How do they look?

 

Is the Cylinder head side where the rubber boots fit in good shape with no gouges, cracks or corrosion, are they clean ?. If it is sucking air, there aren't that many places for it to happen.

-Cylinder head manifold mount - cracked, corroded , gouged ??

-Rubber Manifold boot - these are new and you have swapped some around, so not likely the issue

-Rubber Air-box boot - if cracked it could be sucking your starter fluid spray there (?) if your shooting starter spray at the bottom of the carb it has a similar chance of getting sucked up by the airbag boot as it does the intake manifold boot.

-Mounting Boots/carbs correctly - looks fine in the pics

-Pilot screws o-rings - you mentioned they're new, so they should be ok

-Vacuum sync port on Intake #2 - is this vacuum port properly plugged up ?

-Vacuum for fuel ?? I assume this bike has no vacuum port for the fuel petcock operation and its an electronic pump (?) if it did have a vacuum port for the fuel valve, id say check that.

Instead of spraying the bottom of the carb bowls with the starter spray, try being more specific and targeted with it. specifically spray it on the intake boot between the carb and head. then try on the air box boot etc. Be careful, spraying starter fluid spray can be risky.

 

I sprayed on the bottom of the manifold and doesn't suck air from that, no RPMs increased so I guess all fine there

if I get it right, you mean number 26 and 29 on this scheme, but I have a 1986 model and I don't have this funnels

I can assure that, I sprayed on that port and nothing happens (with the screw or with the vacuum gauge port that needs to be mounted there).

I don't get what you mean here, you mean the tube for the air vent? But I doubt it, anyway yes, it has an electronic pump.

I targeted it indeed, and the RPMs increases in this two parts:

• the top of the intake mainfold, the part in contact with the carburetor (strange thing sometimes happens to the #4 too, so the front one)
• to the base of the air cleaner in contact with the top of the carburetors

Do you find useful the smoke machine to find leaks?