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Old 22 November 2014, 15:41   #1
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Right shift engine intallation.

Hi Guys.

I want kindly to ask if somebody there can explain how the right shift installation of the engine affect to the tension which the boat has to leaning to the left,due to the torque of the engine.

Thanks in advance.
Kostas.
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Old 22 November 2014, 18:14   #2
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Offsetting the engine to one side, effectively shifts the centre line of the boat, this makes one side of the boat "heavier" than the opposite side & counterbalances the torque of the prop. The amount of offset depends on boat/engine combination.
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Old 23 November 2014, 05:14   #3
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Offsetting the engine to one side, effectively shifts the centre line of the boat, this makes one side of the boat "heavier" than the opposite side & counterbalances the torque of the prop. The amount of offset depends on boat/engine combination.
Which is fine in theory,indeed I always thought this was the concensus.
I hear now the Racing boys don't bother,and it's largely a thing of the past.....??
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Old 23 November 2014, 06:27   #4
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Guess a boat can be correctly rigged both ways, centered or shifted to the right. Some talks strongly for the moving right and others to keep it centered, advice depend on whom you talking to. Propellers also makes a big difference, as the height. Think a lot o ribs have been successfully set up with the engine offset.

On my own the previous owner moved it back to the center and told it was better that way, for me its fine and that's anyway how my boats usually have been rigged.

I believe tho idea regarding offsetting is not only shifting the weight but also that thus the boat have two "balance points" that are not in a straight line making it slightly more stable, might be wrong though.
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Old 23 November 2014, 06:31   #5
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Some of the Seariders (SR4 and SR4.7) have the console and jockey seat offset as well. I have always presumed that was to counteract the turning effect of the prop.
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Old 23 November 2014, 07:01   #6
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Some of the Seariders (SR4 and SR4.7) have the console and jockey seat offset as well. I have always presumed that was to counteract the turning effect of the prop.
That would be a bit drastic on a small Boat...because they're pretty narrow,more to do with load/casualty carrying capability I hear Chris.
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Old 23 November 2014, 07:09   #7
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Makes sense, you could lie a casualty down the port side.
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Old 23 November 2014, 07:15   #8
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I agree with C-NUMB,and also regards to the weight shifting.

Also I think that when we move the engine from the center,-to the right-we extend the arm from the center,with result to have bigger moments at the center line,and maybe make the phenomenon -leaning to the left-worst. arm x weight(force)=moments.

Mine (XS-550) with opti125 has a right shift,and leaning a little to the left at cruise,and with all the loads at the center.
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Old 23 November 2014, 07:45   #9
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I agree with C-NUMB,and also regards to the weight shifting.

Also I think that when we move the engine from the center,-to the right-we extend the arm from the center,with result to have bigger moments at the center line,and maybe make the phenomenon -leaning to the left-worst. arm x weight(force)=moments.

Mine (XS-550) with opti125 has a right shift,and leaning a little to the left at cruise,and with all the loads at the center.
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Old 24 November 2014, 09:41   #10
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My Merc is set dead centre, and she travels flat & straight.
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