1992 Yamaha 150 pro v

[beetlejr]

Hi there, i have a 1992 Yamaha pro v model p150TLRQ. It idles great and i put muffs on it and run it and works fine, but when at the lake it comes out of the water good and get up to about 30 or 40 mph and then it starts bogging down on me all the way down to 10 mph. i just replaced the spark plugs, dont know if that could be it or not. previously changed fuel filters with no luck. Any ideas?? Thanks

[erniefish]

Did you check fuel pick up, try a remote tank if possible

[99yam40]

monitor fuel pressure/vacuum to see if that is your problem.
It will show if there is a restriction

[beetlejr]

Thanks, will try and get back to you.