Idles very rough-smokes a lot

[Snoopy-2]

I have a 115 hp 98 Johnson 60 LV
It starts almost as soon as I turn the key BUT it runs very rough at idle and low speeds, even after it warmed up.
Once I advance the rpm's it runs smoothly and very well.and smokes seems to stop.
Is there any idle settings on the carbs and can they be adjusted when the motor is warm and running.
The motor manual l show a idle needle for each carb but they are a son of a gun to get at while running.
The plugs always appear dark and oil wet even though engine runs strong-could the VRO be acting up and letting in to much oil?
Suggestions welcomed-Thanks

 

[Bosunsmate]

yes it could be playing up, lots of people pre mix.
Im not sure how to disconnect it on that motor to test with premix.
yes there are needle valves, much easier if you haave a water tank

 

[racerone]

Compression test is the first thing to do.

 

[boobie]

Sounds like you're going to have to get to the idle adjustment screws. Also check the motor temp to make sure it's running warm enough.