I just recently sold my 1992 yamaha waverunner iii (650cc) and the new owner called and said that he was experiencing hestitation issues. I am the second owner and in total have ridden this ski approx ten times. I just recently changed the fuel filter, the spark plugs and flushed it out. It starts fine and will run at about 10 mph but then sounds/act like it wants to bog out. Any suggestions anyone? I feel horrible. Hopefully its just a quick fix.