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Old 02 September 2015, 13:30   #1
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Country: UK - England
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Boat name: Jacinda Too
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What size Engine?

Having my Rib now stored in France, I'm now using my old Yamaha 3.2 sib on and around The Dart. It has an 8 hour Evinrude 2 stroke which meets on the plane fine with 2 but struggling to do much with 4 adults.

Thinking about getting a 15 hp replacement.

Do you guys think this will give the power I need?

Will such an engine be handleable, ie in and out of car etc??

Any advice gratefully received
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Old 02 September 2015, 13:32   #2
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Obviously that was 8 hp (predictive text)!!!
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Old 02 September 2015, 14:21   #3
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Boat name: Salty Cheeks
Make: Honwave
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Engine: 20hp 2stroke Mariner
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Quote:
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Obviously that was 8 hp (predictive text)!!!

Hi

What's the weight of the 4 people.
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Old 02 September 2015, 14:23   #4
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Boat name: Nimrod II
Make: Aerotec 380
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I've used a 9.8 probably the same weight as your 8hp (around 26kg) and now use a 15hp 2-stroke (35kg). Outboards around 26kg are a doddle in most situations... the 35-38kg 15hp 2-strokes manageable but slightly more awkward on a slippery slipway or over rocks... but never a problem if you use transom wheels then lift the outboard the shortest distance from car to boat... then the boat becomes your outboard trolley.

Regarding power/performance it is boat dependant but in general there's a huge step up in readiness to plane and maximum speed when upgrading to a 15hp.

Much depends on the size of your adults though... four beefy guys and some kit can make it harder to plane with a 15hp... you only need a slightly heavier SIB with such a load and 20hp is better... if you can lift one ok.
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Old 02 September 2015, 14:42   #5
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Thanks. That's all useful . Might even look at a 20hp as it seems my family are turning into Giants!
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Old 02 September 2015, 16:40   #6
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It might be OK with how you want to operate this boat but it's on the small size for 4 adults... wonder what hp it's rated to... you could be maxing it out in all respects... perhaps a larger SIB would be a good starting point?
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Old 02 September 2015, 16:45   #7
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Country: UK - England
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I have 380HD quicksilver SIB with a 2 stroke 25 and it'll do 20kts and plane with 3 adults and a kneeboarder on the back.

It's actually up for sale at the moment and if it's on the River Dart i'm in Paignton to local to you.
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Old 02 September 2015, 19:32   #8
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Make: humber 5.5
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a 15hp should do what you want my honwave 3.2 airfloor easily pops on the plane with 3 very heavy adults on board. 2 males at 17 stone each and a 14 stone lady
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Old 02 September 2015, 20:50   #9
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Quote:
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a 15hp should do what you want my honwave 3.2 airfloor easily pops on the plane with 3 very heavy adults on board. 2 males at 17 stone each and a 14 stone lady
Hi

What pitch prop ate you running
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Old 02 September 2015, 21:54   #10
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Country: UK - England
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Thanks beer belly that's useful.

Not sure what pitch the prop is- and fair point a finer pitch may help, but suspect 8 hp just isn't enough.

As the boat is in Devon and I'm now back in Northumberland I'll check when next down.
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Old 02 September 2015, 21:56   #11
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Ruddy 93. Sounds interesting but was hoping to only change motor at present as the inflatable is good, but will bear it in mind.
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Old 02 September 2015, 22:30   #12
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the prop is the standard size for a 2006 mercury 15hp 2 stroke sorry I don't know the pitch
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