1987 yamaha 9.9 2 stroke

[longlakesd]

I got a yamaha 9.9 1987 model sh and it idles down good but when i run it at full throttle it seems very underpowered. I was thinking about adjusting the carb to see if that will fix it ... any suggestions?

P.S.
bought the motor used from a sketchy outfit so perhaps they tried to adjust it and screwed up the high idle.

thanks

[boats.net]

Run a compression test, check to see what pitch prop is on it.

[longlakesd]

could the high idle be out of adjusstment ?