1992 115 hp yamaha 2 stroke miss

I have a 1992 2 stroke 115 hp that starts up but does not run over 10 mph at full throttle until I have traveled about a mile on the water. Fuel pump has been replaced carbs checked and adjusted. Started to do this last year. Have had it to a yamaha mech three times and spent nearly $900. and the problem is still there. He said everything checks out, even sea trailed it twice. He found two screws loose on the cdi module and tightened them said that could be it. It wasn't the fix I needed. Could a coil be bad and working once it warms up? Does the cdi module need replaced?

Usually the issues that arise when things heat up are the opposite of the problem you're having i.e. coils heat up then start mis firing etc.
Have you tried running the engine with a portable fuel tank? That's an easy way to rule out any problems with the installed fuel tank (if you have one).
Are the thermostats installed?

Is the engine getting up to running temp?

Docksidemarineservices said:

Is the engine getting up to running temp?

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Yes the motor warms to proper temp. Motor runs good with muffs. Sink and link, timing spark and compression all good. Had 2 loose screws on cdi. Tightened and still doesn't run when launched. Coil harness, starter, trigger ok.