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I am working on a 1995 Seadoo sportster. I bought it with 52 hours and a seized engine for $300 including the trailer. I put a new 720 engine in it. Now I am trying to tune the dual mikuni carbs 
Carb bodies are sealed tight. I soap tested them at pressure. No air leaks in fuel lines
Pop-off tests are in range
low speed adjustment: 1.75 turns
High speed adjustment: 0 turns
I'm using 1.2mm needle valve/seats
My first attempt I used the lightest arm spring. That caused fuel to leak into the crankcase overnight and hydro locked the engine.
My second attempt to rebuild the carbs, I used the heaviest spring. That fixed the hydrolock problem but caused fuel starvation (starts great, but engine doesn't rev properly)
I just ordered the black springs from ShopSBT
But before I pull the carbs yet again, will opening the high speed adjustment help with revs?
Carb bodies are sealed tight. I soap tested them at pressure. No air leaks in fuel lines
Pop-off tests are in range
low speed adjustment: 1.75 turns
High speed adjustment: 0 turns
I'm using 1.2mm needle valve/seats
My first attempt I used the lightest arm spring. That caused fuel to leak into the crankcase overnight and hydro locked the engine.
My second attempt to rebuild the carbs, I used the heaviest spring. That fixed the hydrolock problem but caused fuel starvation (starts great, but engine doesn't rev properly)
I just ordered the black springs from ShopSBT
But before I pull the carbs yet again, will opening the high speed adjustment help with revs?