[shanesgp1200r]

having problems with prop spin or cavitation on take off seems fine every where else have to back right of throttle to get going then fine.
looked at impeller and cone and no damage can be seen on them the ski is totally standard at the moment and wondering if this is a problem with the gp 1200rs.

 

[JUST-IN-TIME]

did you measure clearance?

 

[D.Fox]

have the problem often if u get any sand while riding in the impeller it will do that try to ride it plain out many times shut the ski down while wide open and try to flush out the impeller eventually it should plain out and run fine

 

[Kelly_A]

What Just-In-Time said.

Check the clearance between prop and wear ring. Over time sand will erode the ring and prop. There may be no visible damage to either component, but the gap gradually grows larger until you experience the hole-shot cavitation you describe. Short of something like fishing line or ski rope wound in the pump (which you could see) there's really nothing else that could cause cavitation to just appear on a stock ski.