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Old 18 July 2016, 16:55   #1
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* Help! 3.4m dinghy inflatable what size outboard should i buy**

Hi Guys

Please help....bought myself a 3.5m zodiac dinghy....2nd hand ebay purchase.

I need to now source a outboard which size outboard should i use.

My dinghy will be used on the river Thames, lakes etc, i have small kids so need it for days out carrying a max of 6 people.

Im not intending to use it on the sea, however it will be nice to go and explore the coves on the coast hence inland use will be a nice options for the future.

option1
what size outboard should i get for...lakes the Thames and canals.

Option2
to use very rare occasional use on sea inshore to explore coves etc, may never happen

Ive seen 3.5hp outboard and they seem very fairly priced at 550gbp, being just under 13kg easy to handle.

4hp seem more expensive....one off use on the sea might not justify carrying the extra weight and paying the extra $$$

look forward to your replies....thanks in advance
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Old 18 July 2016, 17:09   #2
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Max,

Welcome to the forum...lots of advice here to keep you on track... even if a bit grumpy at times!

Some pics or telling us the exact Zodiac model might help give best advice.

Generally 6 people is too many for a SIB around 3.5m.

Pottering on inland rivers even a 2hp will push a sib but you may not have enough power to steer easily when heavily laden... SIBs tend to skid and need little busts of power to point in the right direction.

A 4hp is really an absolute minimum at sea with a 3.5m even if just 1/2 up and even then it will feel gutless and you will have no reserves against difficult sea/tide/weather conditions. With maximum amount of folks the boat is rated for you need much more power to make safe progress in the sea.
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Old 18 July 2016, 17:20   #3
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hi the model is zodiac club 6 the dinghy itself weighs around 45kg.

what about use on rivers, lakes and canal, would i get away with a 2.5...or 3.5hp.

thanks
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Old 18 July 2016, 17:58   #4
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is it the "Club 6" in this brochure?

http://www.zodiac-boats.co.uk/acatalog/club2008.pdf

If so it's the same as the 360 Acti-V Fastroller I owned a few years back. Very light and went well for any given outboard size but ideally designed for 10-15hp.

Really it's the type of SIB made to plane and that will need at least an 8-10hp lightly laden. It has a max rating of 15hp and I doubt it would plane 6 up even with a 15.

Any engine will move it on the rivers given a windless day but even on a river it's asking a lot of a 2.5hp if you had 6 folks.
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Old 19 July 2016, 09:24   #5
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I would say a minimum you must get is 10 HP.

I'm sailing on Thames, my boat is kept on a swing mooring. When the tide reaches 3-4 knots, and this is not unusual, I struggle to make 200 yards from my boat to the shore. My dinghy is about 10ft with a Tohatsu 2.5 HP, and being alone is sometimes quite frightening how fast and strong the tide can be.

Otherwise, I have an inflatable 3.65m which is rated 20hp max. It's a aluminium solid floor and weight about 120 kg, plus myself and some gear and I would not go for below 10hp. I actually have a 20 HP and a 25 HP for this boat.



From my experience on Thames, I would suggest to have some good power reserve, for your own safety. The navigation is busy here, tide is strong and sometimes you really need to put a WOT to stay safe. Cheers
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Old 19 July 2016, 11:01   #6
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RIBase
agree with all said i would max it with the 15 hp then you have the best options available.
ok the engine is a bit heaver and you could pick one up secondhand for a bit more than a new 3.5 hp nothing worse than under power IMO. if taking 6 people with you plenty to help carry stuff if alone transom wheels or a launching trolley loads of ideas in the SIB section
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Old 19 July 2016, 12:32   #7
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Make sure to get a pressure gauge or a Bravo electric pump, or you'll have difficulty planing with any engine... the air floor's pressure is extremely important to the performance of the boat.
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Old 19 July 2016, 12:33   #8
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thanks for all the replies giving me lots to think about, I do hear the thames can be rough at times...im totally new to all of this, will be sticking to the non tidal bits of the thames....with this in mind will a 3.5hp do the trick?

maybe in the future once im comfortable with the boat look at taking it on tidal parts of the thames, if im brave enough inshore sea use, granted i will require a large outboard or such use.

thanks again
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Old 19 July 2016, 12:44   #9
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Pootling along the quiet non-tidal section a 3.5 would probably be OK but I'd go for a 6hp four stroke in that situation. Just avoid the really tiny buzzy air cooled jobs whatever you go for.
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Old 19 July 2016, 13:02   #10
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You seem set on 3.5hp motor why?
9.9/10hp is a better buy ideally a 15hp, perhaps look at 2 stroke of cost and weight is a big issue.
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Old 19 July 2016, 14:44   #11
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Quote:
Originally Posted by max2016 View Post
thanks for all the replies giving me lots to think about, I do hear the thames can be rough at times...im totally new to all of this, will be sticking to the non tidal bits of the thames....with this in mind will a 3.5hp do the trick?

maybe in the future once im comfortable with the boat look at taking it on tidal parts of the thames, if im brave enough inshore sea use, granted i will require a large outboard or such use.

thanks again
When I bought mine, a 3.65m, I had a Honda BF5 and I made a day trip from Richmond to Battersea Bridge.







It took 2 of us plus pack of beer - 2 hours to go from Richmond to Battersea Bridge, following the tide. We never planed and were going about 8knts.

Then we went to a pub and few Guinness later we missed the tide. I started to punch the tide, but for 20 minutes I could not pass a buoy, the boat was literally staying at the same place at wot.

We moored it at the Chayne Walk pier in Chelsea, and gone drinking for 3 more hours. Then we could slowly come upon the Thames.

The return trip took about 6 hours. The next day I sold the engine on eBay and invested in a 20 HP.

Think tide when it comes to Thames
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Old 19 July 2016, 18:42   #12
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Hi there. I wish i could ask the same question. I ordered a kolibri km330.cant wait. Its 3m30cm. I will (have to) go with 5hp 4stroke. Coz in netherlands if the boat makes more than 20km/h i need a sailing license :-(.
With a good petrol 5hp will do the trick [emoji41]

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Old 19 July 2016, 18:46   #13
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Quote:
Originally Posted by Akira View Post
I would say a minimum you must get is 10 HP.

I'm sailing on Thames, my boat is kept on a swing mooring. When the tide reaches 3-4 knots, and this is not unusual, I struggle to make 200 yards from my boat to the shore. My dinghy is about 10ft with a Tohatsu 2.5 HP, and being alone is sometimes quite frightening how fast and strong the tide can be.

Otherwise, I have an inflatable 3.65m which is rated 20hp max. It's a aluminium solid floor and weight about 120 kg, plus myself and some gear and I would not go for below 10hp. I actually have a 20 HP and a 25 HP for this boat.



From my experience on Thames, I would suggest to have some good power reserve, for your own safety. The navigation is busy here, tide is strong and sometimes you really need to put a WOT to stay safe. Cheers
Why ну погоди? [emoji1]

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Old 19 July 2016, 18:54   #14
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Волчара ;)

Quote:
Originally Posted by kolbris View Post
Why ну погоди? [emoji1]
Cause you need some good push
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Old 19 July 2016, 18:56   #15
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Quote:
Originally Posted by Akira View Post
Cause you need some good push
Oh yeah, i remember that part [emoji1] .

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Old 19 July 2016, 19:01   #16
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Quote:
Originally Posted by kolbris View Post
Hi there. I wish i could ask the same question. I ordered a kolibri km330.cant wait. Its 3m30cm. I will (have to) go with 5hp 4stroke. Coz in netherlands if the boat makes more than 20km/h i need a sailing license :-(.
With a good petrol 5hp will do the trick [emoji41]
I would personally advise to get a minimum ticket. It greatly helps with basic understanding, trip planning, navigation etc.

I pass a next ticket or go for miles building (on a sailboat) every year, and the more I learn, the more I see how much needs to be learn for a safe boating

Get on your 2 days course and you will not regret the money spent, plus you remove all restrictions in terms of power/speed
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Old 19 July 2016, 19:07   #17
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Thats a good advice.

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Old 24 July 2016, 20:38   #18
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I am going to be the first on this thread to say it....Tohatsu 9.8 2 stroke.

Weighs 26kg, same as a 4/5/6 hp 4 stroke and should provide all the power reserve you need.

Ideal engine for that boat.
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