Bayliner Trophy 20.5Ft and Yamaha 150Hp. Which prop?

Discussion in 'Props' started by mallia.s, Nov 23, 2009.

  1. mallia.s
    Joined: Sep 2009
    Posts: 25
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    Location: Malta - Europe

    mallia.s Junior Member

    Hi guys!!

    A friend of mine asked me to do some research for him, to acquire any info regarding the adequate prop for a 20.5Ft Bayliner Trophy, having a 150HP four stroke Yamaha motor. He currently has a 19cm prop, but only manages to attain 5000rpm of the 5000-6000rpm range stated by the manual. It is also stated that 150HP is achieved at 5500rpm.

    Lately he had tried a 17cm prop, which allowed the engine to rev at a max of 6000rpm. This is great, but obviously the top speed decreased from 29kts to about 19-20kts if I'm not mistaken.

    Using the 17cm prop is better for fuel economy and engine lifetime, but is there some prop model that maybe has a higher pitch? To try and attain the top speed.

    Any ideas?

    Thanks in advance for your help and consideration!


    Regards

    Steve
     
    mallia.s, Nov 23, 2009
    #1
  2. mallia.s
    Joined: Sep 2009
    Posts: 25
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    Location: Malta - Europe

    mallia.s Junior Member

    anybody?
     
    mallia.s, Dec 15, 2009
    #2
  3. Kay9
    Joined: Oct 2006
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    Location: Central Coast Oregon US.

    Kay9 1600T Master

    Kay9, Dec 15, 2009
    #3
  4. Frosty

    Frosty Previous Member

    Many boat owners use 2 choices and carry 2 props. They have found ,as you have that the best prop lies between the 2.

    The choice of which to use today lies in what you are doing today.

    Or contact a prop dealer who should have a dozen to try including 4 bladers, ally, stainless etc
     
    Frosty, Dec 15, 2009
    #4

  6. Typhoon
    Joined: Mar 2009
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    Location: Australia

    Typhoon Senior Member

    You could get the 17 prop cupped and see how that goes.
    Cupping usually knocks a couple hundred rpm off teh engine and increases top speed a little.

    Regards, Andrew.
     
    Typhoon, Dec 20, 2009
    #5
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