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Old 25 April 2006, 19:21   #1
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Country: UK - Channel Islands
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Boat name: Barney
Make: Scorpion
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Jacking Plate

I've got a mate who reckons I should fit one of these and a cleaver prop to my Opti:

http://www.bobsmachine.com/main2004.asp

and bigger picture at

http://www.jerrymartincompany.com/docs/1391-x1.jpg

Wondered if anyone had any experience of these - apologies if this has been covered before.
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Old 25 April 2006, 20:02   #2
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Country: Netherlands
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Boat name: smokkelaer
Make: revenger
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I am using a jackplate on a 225 opti. It gives you the possibilaty to raise the engine at higher speeds end it gaves a good acceleration as you keep the engine deeper in water.

Cleaver props I would'nt reccomend on a rib. Yes it gives a great topspeed but that's all it does. On lower speeds and in combination with some load it's the wrong prop.

I am using a Tempest plus 23 and it gives an easy 60 knots.
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Old 27 April 2006, 08:47   #3
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Does your mate have any first hand experience of that gear on the same or very similar boat to yours?

In our experience Stainless Marine do better Jack plates, although for leisure use a Bobs one should be fine. If you have props that you can borrow by all means try a cleaver although I doubt they would be any good on your boat. It depends on what you are trying to achieve. Do you still want to ski and cruise or are you going for top speed ignoring all else?

Beware of Jack plates - 2 things to remember: Bob's have a lot of bolts to come loose, and they need regular maintenance, you can also lift them too high and starve the engine of cooling water, and it doesn't take a genious to work out what that will do to your engine!

They also introduce "setback" to the engine ie the engine will be spaced further back from the transom - the Bob's ones come with different amounts of set back as well - this can also alter the handling of the boat considerably as well!

Hope that helps a bit?
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Originally Posted by Zippy
When a boat looks that good who needs tubes!!!
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Old 27 April 2006, 09:04   #4
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thank god for that cookee, iam just fitting 2x gorrila 2 at the moment on my ribex boat

have you any advice 7' lifters straped together
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Old 27 April 2006, 10:28   #5
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Quote:
Originally Posted by danny
I am using a jackplate on a 225 opti. It gives you the possibilaty to raise the engine at higher speeds end it gaves a good acceleration as you keep the engine deeper in water.

Cleaver props I would'nt reccomend on a rib. Yes it gives a great topspeed but that's all it does. On lower speeds and in combination with some load it's the wrong prop.

I am using a Tempest plus 23 and it gives an easy 60 knots.
Sorry, knots must be miles. we have achieved over 100 kmph and that is more than 55 knots.
We have made a better topspeed with an 25 pitch tempest with big vent/holes plus, but acceleration with the 23 is alot better and we keep the vents a bit smaller.
A four blade trophy was much better to handle the boat through rough water but the topspeed came down 4 to 6 miles.

A big prop as a Cleaver or else in combination with a lift will surely give more risc of having less coolingwater but your Optimax has an low water pickup. Therefore you can bring it up alot without having to worry about the cooling. Be ware that this only works safe on flat water.

This pic will give you an idea of lift in combination with a surfaceprop.
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Old 27 April 2006, 20:09   #6
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Coming to the conclusion that I'll try a 4blade 21/23 prop first, before messing with jacking plate. I still want to ski off the boat, so if I can gain a few knots without knackering the low down grunt, I'll be happy.
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Old 28 April 2006, 20:10   #7
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Quote:
Originally Posted by RIVA
thank god for that cookee, iam just fitting 2x gorrila 2 at the moment on my ribex boat

have you any advice 7' lifters straped together
Not sure what you mean?
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When a boat looks that good who needs tubes!!!
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