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Author Topic: Speed boat Motor?  (Read 226 times)

Gardener

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Speed boat Motor?
« on: November 15, 2018, 01:30:07 PM »

any ideas for a low drain brushed motor running on 7.2v battery for a speed boat ?
Thanks
Dave
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Martin [Admin]

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Re: Motor
« Reply #1 on: November 15, 2018, 02:27:19 PM »


"speed boat", how big.... how fast?

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Netleyned

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Re: Motor
« Reply #2 on: November 15, 2018, 02:30:48 PM »

Don't think Low Drain and Speed Boat motor
gel too well <:(
Ned
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Gardener

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Re: Motor
« Reply #3 on: November 15, 2018, 03:02:08 PM »

30 long not really fast
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Martin [Admin]

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Re: Motor
« Reply #4 on: November 15, 2018, 06:15:31 PM »


Can you still get the Graupner 700BB Turbo motor?
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Gardener

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Re: Motor
« Reply #5 on: November 15, 2018, 07:29:21 PM »

Will look up thanks  :-))
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JimG

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Re: Motor
« Reply #6 on: November 15, 2018, 10:21:03 PM »


Can you still get the Graupner 700BB Turbo motor?


Definitely not a low drain motor.
Jim
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Ken G121

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Re: Speed boat Motor?
« Reply #7 on: November 16, 2018, 07:59:38 AM »

Hi
Not an expert on the fast stuff, I use a couple of low drains in my static dive U47 they only pull a couple a amps each and it definitely does not come up on the plane. Again no expert but I should think 100 to 150 watts per motor sounds fun and nearer 12v to keep the current lower
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malcolmfrary

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Re: Motor
« Reply #8 on: November 16, 2018, 11:17:57 AM »

30 long not really fast
Hull speed for 30" is about 2.5 mph.
Motor needed to get there depends on the hull type.  A narrow one like a warship, a 385 will do fine, a broader hull like a tug will need a bigger motor because more weight of water is having to be shoved out of the way.  Then there is the quesion of using the right prop to convert the motor power into moving water to best effect.
Different for a planing hull, but that means more power to get on, and stay on, the plane.  In turn this means higher current.
But, as said earlier, speed and low current don't go together.
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Gardener

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Re: Speed boat Motor?
« Reply #9 on: November 16, 2018, 12:03:05 PM »

 :-))
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