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Old 14 July 2006, 12:43   #21
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Quote:
Originally Posted by Andy_Rs600
throttling back isn't going to affect the flight of the boat at all


I think you're confusing throttling back slightly with throttling right back

I find that just by backing off 500-1000 revs just as the boat goes airborne and back on with it as the boat re-enters the water gives a softer landing and less stress on the engine and drive train.

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Old 14 July 2006, 12:47   #22
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Quote:
Originally Posted by davidmanning
I think you're confusing throttling back slightly with throttling right back

I find that just by backing off 500-1000 revs just as the boat goes airborne and back on with it as the boat re-enters the water gives a softer landing and less stress on the engine and drive train.

DM
thanks dave, the answer i was waiting for as this is my view on it too

chris
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Old 14 July 2006, 14:12   #23
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Quote:
Originally Posted by davidmanning
I think you're confusing throttling back slightly with throttling right back
Not confused, once the prop is out of the water, you can do whatever you want with the throttle, and it can't possibly affect the boat, because there is no drive anyway! What i said was, "Once the prop is out of the water, throttling back isn't going to affect the flight of the boat at all, only the landing."

Thus, if the boat leaves the water at 5000RPM, and in flight you reduce throttle to 3000, then back to 5000 for the landing its exactly the same as leaving it at 5000, except less impellor wear and less over-rev.

Quote:
Originally Posted by davidmanning
I find that just by backing off 500-1000 revs just as the boat goes airborne and back on with it as the boat re-enters the water gives a softer landing and less stress on the engine and drive train
Yep, but my timing isn't that good, or maybe i very get the boat out of the water for long enough to fit that cycle in!


Also back on the original topic......

Take the cowling off after every trip out and make sure the inside is totally dry, especially if it's been an 'interesting' day out.
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Old 14 July 2006, 14:22   #24
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when the prop leaves the water it is my view that the engine most likely just hits the rev limiter straight away in the higher throttle positions


by backing off slightly you are keeping the revs from screaming to the rev limiter and hopefully providing some protection to the engine from earlier failure. then getting the revs right as the prop reenters the water is all part of the fun of the jump in my view

getting it right is a good feeling but hopefully noone throttles back fully so as to induce that drag on the landing, that would not be helpful

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Old 14 July 2006, 14:27   #25
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Quote:
Originally Posted by Hugh Jardon
hopefully noone throttles back fully so as to induce that drag on the landing, that would not be helpful
Think your idea of "not helpful" is different to mine
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Old 14 July 2006, 17:50   #26
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Quote:
Originally Posted by Andy_Rs600
What i said was, "Once the prop is out of the water, throttling back isn't going to affect the flight of the boat at all, only the landing."
Not so!

You might like to consider what effect the forces from the prop and flywheel are doing to the boat when it's airborne while your engine is screaming its knackers off.

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