Rebuilt carbs new jets to factory #s I'm trying to sync using home made manometer..carb 2 pulls so much vac it gets by restrictor and no time to adjust others..frustrated...carb pilot screws adjusted to 2 turns book says no adjustment for carb 2..but there is a pilot screw.. bike runs good..little sluggish in low rpm throttle response..bogs a bit. Any ideao should I try to unscrew pilot screws on others more? I'm guessing that unscrew decreases vac..screw in increases?

 

You need to remove the fuel tank and run the bike from another source, or a longer fuel hose to stock tank, but the tank has to be off to make the adjustments. There are 3 screws on the throttle linkage visible from the top of the carbs. The center adjusts cylinder 1 & 2 vs 3 & 4, and the left & right screws adjust the pair of cylinders separately. There are pictures and all the info in the FSM.

Set all the pilot adjustments back to stock and then you'll need to start by adjusting the left screw to get cylinder 1 & 2 closer in balance. You can get a rough adjustment by just cranking the engine and setting the sync, then you should be able to start the engine without pulling the fluid too far through the tube.

The pilot screw adjustment info is also in the FSM, but you'll need to get the carbs balanced better first to set it properly.

 

thanks, im using an auxillary tank, sounds like i need to remove the airbox to get to the throttle linkages? The clymer manual only shows the pilot screw locations, not really impressed with it..

 

You can download the factory service manual in the sticky at the top of the forum for free.
You have to have the tank off when you adjust. I did it with everything off, including the airbox.

 

You can use a feeler gauge under the slides to get them close without running the engine if they are too far out of spec. Then use the manometer.

 

Make sure you have a good seal on all the vacuum ports as well. Even a little leak will cause the mano to go wonky. I'm curious as to what everyone uses for connections to the vac ports... It's really hard to find M5 threaded nipples, either for air lines or greasing applications.

 

I like the look of these, Motion Pro adapters, but haven't tried them out yet.

I don't have a good picture of the adjusting screws on hand, but there should be something in the FSM that shows where they are.

 

I ordered the motion pro adapters real nice, two long ones two short ones connects good, .. so how much clearance should the butterflies have, ive got them so that a little bit of the first hole is showing, I cant even get the smallest feeler gage under it .010/.254mm, tore out the carbs again today to adjust all the pilot screws easier, took them all out cleaned them(forgot to do that 1st time) didn't lose the o ring and washer, checked butterflies, thinking of ordering some new intake boots....old ones are ok, but may have a leak there?

 

I haven't done the feeler gauge thing for a while but as I remember you need a thin feeler gauge...like .005". Your not setting them just trying to get them all the same. The idle stop opens them up.

 

There is no set distance. The purpose of the feelers guage is so they are all the same. I personally use a sewing needle.
Once they are all balanced you will use the idle adjustment screw to set properly set the idle. On a f3 its 1200 rpm.
One important thing to remember is the bike needs to be t operating temp when you balance the carbs. If you do it on a cold engine your readings will be different when the bike warms up.
Also, I use the motion pro adaptors and they work perfect.