gx-rex is bang on the money there, you need to get specific jetski/ motorcycle oil

using car motor oil will shag your clutch marty

2 wheel wreckers have an excellent priced range down in neil st ozzy park, thats where i used to get all my bike fluids from


i'm basing this on the assumption that a jetski has the same wetclutch setup as a motorcycle? i'm no expert on ski's