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Need help with 2005 Yamaha 90hp 2 stroke!

Was running wide open the other day and my yamaha 90 2 stroke lost power. Started it back up and ran but seemed to run pretty rough. Continued to lose power every so often when running open. Eventually began running very rough and I limped back to dock. Lower spark plug has the ground piece bent down touching the node. Changed it and it started back up but was running somewhat rough. Took it back out and ran wide open. Lost power again and started running really rough and barely had enough power to stay up on plane. All spark plugs appear to be ok and are sparking. Gas is only a few weeks old. Any help would be awesome!
Also, if anyone knows a trustworthy mechanic that can diagnose this I would appreciate it.
loss of power
from what you explained, i would take the spark plug with the bent electrode out, and look inside the cylinder at the piston to make sure there was no detination of the piston. i have seen it happen when i was a boat motor mechanic. make sure it is the right plug for your motor. there should be a sticker with the type of plug to use. if your piston looks ok, i would check your head gasket next. if all that fails, make sure your carbs are clean. hope this helps you some.
It could be starving for gas.Next time run it on a seperate fuel system(portable tank).If you can't do that ,then trying squezing the primer bulb to see if it pulling enough fuel to the motor.
The plug is the correct type. Pull them all and watched the pistons cycle back and forth while cranking. Looked fine. I will keep looking. Thnx much.
1st things first
Do yourself a favor and do a compression check on the cylinder that you suspect a problem with first. If that is ok then procede with other advice.
90 yamaha
I had the same problem with a 2006 model. Mine would lose power when running wide open but not at half or 3/4 throttle. Ended up being a screw had backed out inside the carb and would not let the float open completly. When it was wide open it wasnt letting enough gas in to stay running. I was ready to stick a piece of dynamite in it by the time i finally found this. Hope you find out what it is.
Same Experience
Had the same thing on an 04 90. Wound up being a broken rod or something like that. Had to have the block bored and piston rings and rod replaced. Actually checked compression before bringing it in and it had checked out fine but our maintanence guy at work recommended I bring it in and definitly paid of in my case.
Had the work done at performance outboards in Houma, quick turnaround and decent price.
Good Luck