91 Johnson 40hp will only run at full throttle

[homs405]

So I have an issue with this motor that I cant seem to trouble shoot, the basic symptoms are it will not put around but it will only run at full throttle, I have been thinking a fuel issue, or air issue but the carbs were sonic'd not to long ago and I think that should take that out of the equation.

 

[racerone]

A compression test is the first thing to do on a " trouble " motor.------------Also check that you have spark on both cylinders that will jump a gap of 7/16"--Post your test results.