Help with RPMs fluctuating

[impalor419]

I have a 1989 130hp Yamaha outboard that been having problems with. When I accelerate anywhere in between 10 to 4500 rpms it runs great. When I push it to full throttle it goes up to 5900 rpms and then after about 5 seconds it backs down to 5000 and stays there most of the time but will jump to 5100 here and there. When I back off throttle a little it starts going from about 4600 to 4900 rpms. I have just replaced head gaskets, impeller, plugs, thermostats, exhaust cover. The compressions are great. 140psi on 3 and 135psi on the other. The carb has recently benn cleaned and rebuilt. I can say that this problem was going on before everything was done but the exhaust cover.

[99yam40]

That is a 2 stroke and WOT RPM is 5500 I believe, could it be hitting the rev limiter?

Need to check to see if it is dropping spark or if timing is moving off of spec

[rodbolt17]

drop spark on a cyl on that V4 and it will drop at least 1000 RPM.
double check carb float setting,fuel pump, fuel line quick connect(E fuels eat the oring on the engine side) and check for fuel restrictions.