97 gsx loses power at wot

[reddogz12]

i have a 97 gsx that runs and revz fine on the trailer and fine in the water up until about 5000 rpm.but once you try and go wide open under load it will miss and decrease in rpm until you feather the throttle and start the process all over again.it will do it just sitting on the trailer in the water you dont even have to ride the machine.the machine was running fine until this problem suddenly occured.
there is no warning of any kind on the gauges.i have had the carbs apart twice screens are clear everything looks good,blown out fuel lines and drained tank of all old gas,petcock is new,fuel sender in tank is new.plugs are new and are of the resistor type,exhaust hose looks and feels good and doesnt appear to be collapsing,comp is good 180lbs in each cylinder,rave valves move freely and bellows appear to be in good condition.the only thing i havent tried is putting an inductive timing light on the wires to see if either or both plugs wires are losing spark when this problem occurs however i plan on trying this tomorrow.
any recomendations or suggestions would be greatly apreciated.
thanks cliffy

[Technical Support]

Re: 97 gsx loses power at wot

the carburators most likely are the cause for your trouble. Set them to factory specs and go a little rich. Make sure your pop-off is where it needs to be.

[reddogz12]

Re: 97 gsx loses power at wot

carbs are all good checked them twice

[Bill O'Neal2]

Re: 97 gsx loses power at wot

Then why when you "feather the throttle" it starts running better? My guess is a carb problem.

[reddogz12]

Re: 97 gsx loses power at wot

by feathering i simply mean letting off and getting back into it.it will rev briefly and then begin to act as if its hitting a warning limiter.for instance on polaris domestic engine watercraft if they become hot or low on fuel they kick in a limiter that will not allow to go above 4500 rpm.i dont know what else could possibly be wrong with the carbs that would be working fine one minute and acting like this the next and not show signs of a problem internally.

[Bill O'Neal2]

Re: 97 gsx loses power at wot

Sea Doo's, other than the new fourstrokes, do not have "warning limiters". So that aint it.

A carb can act exactly like that if the diaphram is acting up or the pop off pressure is too low or too high, or a needle is binding or if you left some screws loose inside..or....