Calling all carb guru's

[CaptonZap]

Help, I need reassurance.
I have an 80G that sat for 12 years with gas in the carbs. There was still fluid (You can guess what that smelled like) in the bowls, but the needles where gunked up, as were the jets. Got those all cleaned up, along with the bodies and bowls, (the Pine-Sol treatment is a blessing), and went to put the floats back in.
The float needles have a small pin sticking out the bottom that contacts the float arm. Three of the needles were solid, and the fourth was springy, i.e. the float arm would bounce when it was dropped against the needle, with the carbs upside down. The little pin was spring loaded inside the rubber tipped needle. The other three were solid, and I could not get them to depress, even after soaking in acetone. The springy one seemed to have a different appreance than the other three, as far as surface texture and shine goes, so I don't know if that one was replaced in an earlier ownership.
The question is, do they all need to have that spring loading to keep from hurting the rubber tip on the needle, or can I use them as is? The float heighths were all the same, when sighted down the row with the carbs upside down.
One other question is, on the front top of the carb, in front of the slide diaphram cover, is a tower with a small hole in the brass plug on top. What is the purpose of the small hole, and where does that passage lead?
All information appreciated, CZ

[brcree]

carb needles

Yes Cap, the float needles do need to pop in and out. If these needles don't seat properly you will have gas overflowing into your airbox. I would start over with new ones. Ebays has tons.....check around in here, some members can help out alot with parts! I would measure the float levels to make sure they are in spec.

[TopCatGr58]

I'm not an actual Carb GURU, but I know a few things.

You'll need to get some replacement viton tipped float needles, see www.mikesxs.net or www.partsnmore.com as well as other places for them.

The spring affect is necessary to help keep the pressure on the rubber tip during motion, sloshing of fuel, etc. while the bike is running and moving.

The small brass caps are just that, caps that prevent owner's access to the pilot screws. To be able to perform a proper cleaning, they need to be removed, and then the pilot screws...but be careful, there are small metal and rubber washers down in there as well. Then you can spray cleaner thru the pilot jet tower and the pilot screw tower, they are connected. Then you'll need to read about tuning the carbs with these pilot/idle screws. Also being able to perform a vacuum synchronization as well.

You can also get replacement pilot jet screws and washers from mikesxs as well. Just don't ask MIKESXS about them, their liability limits them to only inform about 650's.
T.C.

[DGXSER]

Like TC stated, you need to pull those pilot screws under those caps. Typically, you and put a small drill bit in them and pull them out. Be careful though the mixture screw is not far below that cap and you do not want to drill into it.

Before removing the mixture screws, turn them clockwise counting the turns until the seat or bottom out. Write down each ones setting then remove and make sure you get the spring, washer and rubber o-ring from each one. When you get everything sparkly clean in there and put the new or cleaned screws in, put them at the same settings your old ones were at for a good starting point.