mikuni 22mm flooding

My set up
-212 non-hemi predator
-nr racing ported 18cc Honda head milled .050
-cm push rods stock length
-reinforced rocker arms stock ratio
-.016 copper head gasket
-lash caps
-black mamba can
-arc rod and flywheel
-head and side cover studs
-22mm mikuni
-Robertson torque loop header

The carb came with a 95 main jet and 15 pilot jet with needle clip two positions from the bottom. Tried it and didn't want to crank with or without choke, started if you have the throttle wide open, kept flooding and gas dripping out of the overflow hose bad. They sent a 130 main and a 17.5 pilot also, but I think it should've been a 12.5 pilot. I tried that combo with the same results. I tried different positions of the clip and air screw. It's running the best now with the 130 main, 15 pilot, clip in next to the top slot, and air screw out 1.5 turns. I tried squeezing the pulse line with a zip tie to cut down on flow, but didn't help. I've read about putting a return on the fuel line when using a pump with a mikuni. Do I need to order a 12.5 pilot to try? I have a Honda .625 bored carb also the I run on my other motor, would it be enough carb for my setup, I'd like to spin alot of rpms? I just don't know what would be best. I have to run a pump because I need a 2 gal. tank since I run it on a boat and need the extra fuel. Any help will be appreciated.


Banned - Must pay $500
Ok, Some say the fuel pump is too strong.

Install a " T " Or A " Y " in to the line and run the second one back to the tank.
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Are you using a fuel pump with it? Is this a mini with the tank above carb or go kart? Your gas level is too high in the float bowl if it is coming out the overflow, the 130 and 17.5 pilot are fine but you must first fix your issue with the flooding. Those carbs do not work well with a fuel pump and if this is a mini with a frame mounted tank as long as gravity will feed gas to carb get rid of the fuel pump.
I have to run a fuel pump since I have a 2 gal. tank in the boat that's way lower than the carb. I will find the parts for a return this week and try it. I hate to put a fitting on my tank for a return, will it work if I return it to the fuel line before the pump, has anyone tried this or have any pics?
First do you have a filter on the line ? Clean gas a the key anything gets in that carb and it will be a problem . You possibly have debri stuck in the float plunger and that will do it . The carb is perfect for your set up . I just put a brand new 22mm from NR racing on my predator yesterday , installed the 130 main and the 12.5 other and she runs great .
Also with that head and the milling that's done you could had a lot of compression if you have a flat top piston and thin head gasket .
I have a filter between the pump and carb. Not sure what the compression is. I was told around 11:1, I do know that it's an 18cc head milled .050 with a .016 copper head gasket, and the piston is the factory dished with a stock length rod.
If it's hard to pull then you may have the valve lash set to louse , then after it get hot it will be worse . Set your lash at O not 3-4 thou like most will tell you . You want to just to be able to turn the push rods with your fingers . Then when the motor gets hot it will loosen up to the 3 or so that's wanted .