I have pal and jp version and to me it seems like the gameplay on the JP is wayy slower than on PAL. is that normal?

The pal version is faster, but the gameplay itself has slower frames per second than the American and Japanese version. The NTSC versions have normal gameplay than what the pal has.

The gamecube console is slow because of the 1.5 second loading screenings at the end each level, when you are playing the japanese version is kinda slower.

The wii version is a lot better speed to use.

PAL not only has higher top speed for the watercrafts, but also a timer that runs slightly slower than NTSC, resulting in significantly lower final times. The developers were NTSC-based so it seems to have been a somewhat slapdash PAL conversion. Either the timer or speed adjustment alone would have made sense, but both of them together is pretty inexplicable. At any rate, differences are pretty dramatic.