Help! speed and power down...

[Twist]

Hello,
I have found that the power and speed was down. Max speed 90 km/h and the rps max 6400… (Earlier max speed was 113 km/h) I have changed wear ring (the ring was not bad and I think there was no need to change it), but situation the same. Please, maybe anybody have any ideas?
RXT 07' 215

 

[kidcml]

how many hours r on your seadoo ? it might be a supercharger problem

 

[Twist]

64 hours.....