1999 25 hp mercury running rough

by Casey

I have a two stroke, 1999, mercury 25 horse power motor. I've owned it for a year and up until just recently it's ran well. Out of nowhere it doesn't run well at higher rpms. It takes several pulls to start. Once started it cranks fine.

From neutral to about 10 to 15 mph it is solid. After that it's almost like I get no thrust. It revs high and gets plenty of spark, compression, and fuel but she just doesn't respond well. The motor is working far too hard for the result I am getting.
The carb is in great condition even before I cleaned it, top to bottom. Jets look great, minimal debris throughout the entire carb.
New plugs, and gently used plug wires and coils that I replaced too. Flywheel is in good condition. I have had issues with the idle and the pull cord which I addressed.
I'm half way decent with mechanics, but I'm still a newbie when it comes to outboard motors. Any suggestions would be appreciated. Thanks

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