Running Lean

[turbostang]

Ok here is the scoop.

Been fighting a carb problem for a while now, would not rev past 4k and stumbling all over the place.

So I took the carbs apart AGAIN, and did the following

all float levels set to 1.075" dry
wet level 17mm +-1mm
with the 152.5 jets, 90mm pilot jet on the top of the carb, 150 under the diaphragm, and the needle set to the middle it would not rev and was turning the spark plugs white.

now with a 170 main, 152.5 under the diaphragm, 90mm on top with the needle on the closest position to the taper it is stumbling at 5-7k and pulling ok (not great) everywhere else. the plugs are still snow white though so obviously it is still dangerously lean. If I drive through it, it will run ok, but if I hammer the throttle below 3-5k it is very sluggish. Over 6-7k it will run to redline with no noticeable heistation, but it is not pulling at full power.

It has stock airbox with a k&n, cobra exhaust, valves are all adjusted to spec, and is otherwise stock.

The v-boost is working ok and it does not seem to have any broken boots.

Any ideas where to begin.

Here are the plugs.

 

[vmaxinID]

I'm an idiot, but: fuel filter???

 

[turbostang]

I'm an idiot, but: fuel filter???

Filter has been replaced

 

[davidon]

Jet block/Pilot fuel jets (pulled and sprayed out) cleaned?

 

[clintard]

have u tried the propane method to check for leaks on the intake side of things? u can also spray ether or wd40 and listen for a change but i reccomend propane

 

[turbostang]

Jet block/Pilot fuel jets (pulled and sprayed out) cleaned?

Yes, they are all brand new.

 

[turbostang]

have u tried the propane method to check for leaks on the intake side of things? u can also spray ether or wd40 and listen for a change but i reccomend propane

not yet, but I will if I cannot cure it via carb settings.

 

[clintard]

not yet, but I will if I cannot cure it via carb settings.

im no mechanic but thatd be the first thing id do

 

[maleko89]

Jarret, it's strange that 170's make it better. With all the work you've done to your carbs I'm thinking that's not the problem? But, since it's ridable maybe ride it for 30+ miles to break your new parts in and re-evaluate. I'm on a poker run tomorrow but feel free to call my cell.

Mark
#1098

 

[turbostang]

Jarret, it's strange that 170's make it better. With all the work you've done to your carbs I'm thinking that's not the problem? But, since it's ridable maybe ride it for 30+ miles to break your new parts in and re-evaluate. I'm on a poker run tomorrow but feel free to call my cell.

Mark
#1098

I am going to check the o-rings under the v-boost intakes for vacuum leaks as well.
I have ridden it about 16 miles so far, and the correct tune seems pretty close but I am being cautious with it that lean. it gets really hot