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Old 21-07-2006, 10:55 PM   #1
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2.1 Gear Ratio

I have the option of a 2.1 gear box and I have noticed a few racers running 2.1 so can someone please explain the pros & cons of runnning a 2.1.

Thanks guys!
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Old 21-07-2006, 11:56 PM   #2
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2:1 needed when more revs needed,heavy boats or fat feckers,in boat
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Old 22-07-2006, 01:16 AM   #3
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Re: 2.1 Gear Ratio

Quote:
Originally posted by MrRob
I have the option of a 2.1 gear box and I have noticed a few racers running 2.1 so can someone please explain the pros & cons of runnning a 2.1.

Thanks guys!
Its because there is an optimum pitch prop which I think it 27",
For example every time a prop completes 1 full rotatation you loose X amount of speed/engine rpm from the drag of the blades and weight of spinning prop etc.

So the smaller 25" prop turning faster on a 1.87 ratio is less efficient then a 27" on 2:1 ration
so even if the engine with the faster turning 25" prop travles the same distance as the slower turning 27" prop it will be a quicker combination because yoiu are not loosing as much of the engines power through drag.
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Old 22-07-2006, 12:28 PM   #4
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Quote:
Originally posted by hutchy
2:1 needed when more revs needed,heavy boats or fat feckers,in boat
My bat boat isnt heavy and i aint a fat fecker! must be revs then!
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Old 22-07-2006, 08:30 PM   #5
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what prop you running scotty?
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Old 22-07-2006, 10:53 PM   #6
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Quote:
Originally posted by scottyboy
My bat boat isnt heavy and i aint a fat fecker! must be revs then!
i think its my nav!!!!
either that or too many magners!!!!
maybe its because i'm a pie eater?
has your bitch got a ride for little hampton yet??? or does he need some serious ballast!!
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Old 22-07-2006, 11:19 PM   #7
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Re: Re: 2.1 Gear Ratio

Quote:
Originally posted by PuppiesBalls
Its because there is an optimum pitch prop which I think it 27"
I thought it was less than that, around 23", but I may well be wrong.
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Old 23-07-2006, 07:52 AM   #8
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Re: Re: Re: 2.1 Gear Ratio

Quote:
Originally posted by Johnny Boat Dude
I thought it was less than that, around 23", but I may well be wrong.
I thought that aswel JBD. Im sure I heard Burty banging on about it and he said it was 22-24 pitch prop.
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Old 23-07-2006, 09:39 AM   #9
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Yeah but he got it from me and I can't remember where I got it from.
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Old 23-07-2006, 11:34 AM   #10
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Quote:
Originally posted by floater
i think its my nav!!!!
either that or too many magners!!!!
maybe its because i'm a pie eater?
has your bitch got a ride for little hampton yet??? or does he need some serious ballast!!

Believe he has a ride for L.A mate yeah! He's on he strict instruction of bend it he repairs it though! Im racin sat and then bens racing sunday! Has your naviguesser got a ride then?
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Old 23-07-2006, 11:39 AM   #11
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Quote:
Originally posted by MrRob
what prop you running scotty?
Tis a secret! you have a pm matey!
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