Hello again everyone. I'm having another issue with my 2000 f4. Getting ready to take off I get it going, but then if I twist the throttle it slowly goes up in rpms until it eventually goes. It got worse as I drove and it would start to jerk like it wanted to go, but it just couldn't.

It idles fine 1400 rpms. I replaced the jets and put bigger ones in a couple weeks ago because it was running lean. Synced it and it ran perfectly until now.

It goes in 2nd and above and if say i'm slowing down and put it in first and keep the clutch disengaged, but then engage the clutch while in first gear and drive at slow speeds then take off it's fine.

Also I know how to take off well so I don't think its that.

Bad clutch? I saw from other people that playing with the D shaped fuel screw on the carbs might help, but with bigger pilot and main jets, do you want it out more or in more?

 

I would contact DynoJet about your jet question but something that might help is running seafoam or techron Fuel system cleaner next gas tank. might help and its easy.

your clutch wouldn't really slow you down at take off, I would trace your fuel system from the tank to the carbs. make sure the petcock is clean, hoses arnt kinked, the fuel filter is clean and the fuel pump is working. I would start there and get back to us if its none of those.

here are some other things that could be the culprit: (Im not the original author)

Spark weak:
Battery voltage low
Spark plug dirty, broken, or maladjusted
Spark plug cap or high tension wiring trouble
Spark Plug cap shorted or not in good contact
Spark plug incorrect
IC igniter trouble
Pickup coil trouble
Ignition coil trouble


Fuel/air mixture incorrect:
Pilot screw maladjusted
Pilot jet, or air passage clogged
Air bleed pipe bleed holes clogged
Pilot passage clogged
Air cleaner clogged, poorly sealed, or missing
Starter plunger stuck open
Fuel level in carburetor float bowl too high or too low
Fuel tank air vent obstructed
Carburetor holder loose
Air cleaner duct loose

Other:
IC igniter trouble
Carburetors not synchronizing
Vacuum piston doesn’t slide smoothly
Engine oil viscosity too high
Drive train trouble
Brake dragging

 

Put some seafoam in and it helped out a little. Plan on taking it apart tomorrow again and going over everything on the list that I haven't already. It's gotta be a fuel problem

 

Good luck and pm me if you need any help.