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Old 27 July 2012, 07:53   #1
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F9.9FMH Power output

My dad bought himself a new outboard to replace his old two-stroke 9.9, but it seems a bit of a "wet fart" compared to the old engine. Is this something to expect from a four-stroke or is there an easy way to increase the power output? When increasing the the throttle there is no difference in output during the last 20% of the travel on the handle. Any suggestions apart from replacing it with a bigger engine?
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Old 27 July 2012, 08:45   #2
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Is the top speed down or is it just a lack of acceleration?
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Old 27 July 2012, 18:12   #3
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Top speed is down I think. Considering the possibility that the prop pitch is too big, preventing it from reaching max RPM. Have not had the option to check what max RPM is yet. Did a test run with the old 9.9 Evinrude 2 stroke engine today and got 12.5 knots vs 10 knots with the new Yamaha F9.9 FMH.
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