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Old 10-07-2015, 08:28 PM   #1
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Country: Herne Bay
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Yamaha 90 prop recommendations

I'm looking for a new propeller on my Yamaha 90 on a phantom 16. At the moment it's running an aluminium 13 1/4 17 pitch prop. The engine has had some work done to it, although I don't know what, and revs too high with the current prop. Top speed on the gps was 48mph but I'm sure there's a bit more to get with the right prop.
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Old 10-07-2015, 09:10 PM   #2
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Id try a chopper or a yam drag prop. What revs are you getting with the current prop?
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Old 10-07-2015, 10:05 PM   #3
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That speed was at about 5500rpm. The engine will rev much higher, as there is no rev limiter.
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Old 11-07-2015, 12:07 AM   #4
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Quote:
Originally Posted by chrome andy View Post
That speed was at about 5500rpm. The engine will rev much higher, as there is no rev limiter.
rule of thumb is 1 inch of pitch equals 200 rpm. So, if you know what revs your 17 pitch pulls and you know the max of the engine, you can pitch up accordingly. I'd guess between 20 and 22 for a p16 with yam 90.
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Old 11-07-2015, 09:59 AM   #5
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20-22 is bang on for hat set up, you may need to raise the engine to accommodate that pitch though.. Just not to high to require a low water pick up, if you have a stepped transom like
Most just raise it as high as you can go and get a 21 pitch, yam drag or ballistic

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Old 11-07-2015, 08:31 PM   #6
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Ballstic 21 for that mate. we run a ballistic 21 on our rib with a yam 90 and a ballistic on our P18. we also used to run a ballistic on our p18 with a yam 115.
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Old 15-07-2015, 04:04 AM   #7
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Yam drag all day long, 22 pitch you'll see mid 50s
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