Why cut on the carb. if there is a procedure for adjusting it ?EXspyguy said:15, 17 and 19 are all the same engine except the carb and the only difference there is how far the govenor is allowed to open the throttle plate. If you look at where the lever on the butterfly stops, cut some of that away to allow it to travel further thus increasing power.
Check out this attachment, This is the proper way to adjust high speed RPM.EXspyguy said:it is not just an adjusting screw. It's more of a tab that needs to be cut back.