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Old 22-05-2008, 08:05 AM   #1
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Props

I've a Ring 20 with a 2.5 Merc with offshore leg and Sportsmaster 1.78/1 box and a 21" Lazer prop. I've got a spare 22" small hub Lazer can I use it to bring the revs down a bit. Or any idea's as to the ideal prop?
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Old 22-05-2008, 08:57 AM   #2
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Yes, you would see about a 250 RPM reduction if the dia and all other items are the same (Cupping, blade profile & shape).
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Old 22-05-2008, 11:12 AM   #3
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Does the small hub make a difference?
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Old 22-05-2008, 12:03 PM   #4
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shouldn't do
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Old 22-05-2008, 01:44 PM   #5
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Thanks
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Old 22-05-2008, 02:00 PM   #6
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Just a thought when you say hub I assume thats the shaft size.
Overhub Exhaust Vs through hub will make a difference
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Old 22-05-2008, 10:15 PM   #7
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Just a thought when you say hub I assume thats the shaft size.
????
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Old 22-05-2008, 10:42 PM   #8
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22 small hub will increase rpm quite a lot probably by about 500 and should increase speed !! A Small Hub (13 1/2 Dia) 24 would probably be equal to your 21 !! What RPM are you turning on the 21 ??

Bob
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Old 22-05-2008, 11:00 PM   #9
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????
15 spline Vs 19 spline
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Old 23-05-2008, 10:41 AM   #10
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15 spline Vs 19 spline
The splines are the same as my 21 laser but the hub around it where the exhaust comes through is smaller. Anyone got a 23" they want to deal on?
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Old 23-05-2008, 01:08 PM   #11
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Send Nick Surry a PM
He's got a 23" thats too big and he wants a smaller prop
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Old 23-05-2008, 01:28 PM   #12
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Send Nick Surry a PM
He's got a 23" thats too big and he wants a smaller prop

Thanks Burty
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Old 23-05-2008, 02:11 PM   #13
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i've sent you his number by PM dude
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Old 23-05-2008, 02:41 PM   #14
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I've got one too if you have no luck. In great condition. Make me a sensible offer.
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Old 23-05-2008, 06:02 PM   #15
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I've got two 23's Mike, you know they work.
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Old 23-05-2008, 08:29 PM   #16
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I've got two 23's Mike, you know they work.
Cheers Trev
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Old 26-05-2008, 12:57 PM   #17
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whot prop 20ft ring 2.5 200

im running the same set up on same boat, im running chopper props, 26p running 5.8rpm 74mph 2 up, and jus got 24p tested yesterday 6000rpm 68mph 4 up,was running 21 and 23p laser last year didnt find them as gd as choppers.
chris.
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