3.2 aluminium hull rib plus outboard

[Moorsman]

Hi all , I was wanting a small light rib for fishing with probably 6 hp outboard,what would be your recommend be ,thanks

[Locozodiac]

Compared to same size Sib a Rib weights much more. A 330-340-350 size alum hull would be my option compared to a smaller 320 size. A larger size will have less hull drag and be more efficiently powered with a 6 HP motor.

Happy Boating

[Moorsman]

Thanks for your reply,my main criteria is weight,I’m getting on a bit and like to go in shore fishing ,I was told a small aluminium hull rib didn’t weigh much moe than a sib but to launch of the beach would be better ? I don’t need to go to fast so just a 6 hp should be enough,I always use a trailer.

[Fenlander]

>>>I was told a small aluminium hull rib didn’t weigh much more than a sib

And you were told correctly. As an example the Zodiac 3.3m Alu Cadet RIB weights 47kg. That is 5kg lighter than the Cadet 3.4m with wood floor from a few years back... and 1kg lighter than an Excel 3.3m air floor.

If I were using a trailer I wouldn't hesitate to get one of the light alloy floor RIBs... their efficient hard hull will make the best of a smaller outboard compared to a SIB too.

Loco is right that in some circumstances a longer hull can help but around the 3.3m size should work fine.

I assume you are only one or two up? If you could I would consider an 8hp... certainly look into the weights/costs carefully before you decide. Even if you are not looking for ultimate speed it will plane a 3.3 a little better.... but it may be the big jump in weight 6hp-8hp is more than you want.

If you were looking at a used motor a lightweight Yamaha 8hp 2-stroke or Tohatsu 9.8hp 2-stroke would suit probably??

[Fenlander]

I see also the Highfield Ultralight 3.4m alloy RIB is 53kg... bit more than the Zodiac but still way less than a SIB with sectional alloy floor.

[Pecheur Anglais]

Finding my 4.2 rib much bigger than I need when fishing on my own, I bought a Quicksilver 2.9m AluRib last year. I am absolutely delighted with her. Weight just 41kg and an easy launch with dinghy wheels she absolutely flies with a 9.8hp, so would do very well with 6hp.

[Moorsman]

Hi fenlander ,thanks for your reply, I had looked at the 3.3 zodiac and thought about right ,looking at the weight difference between the 6&8 outboards the 8 for me will be to heavy to lift ,which of the 6 hp outboards would you recomend ,
Thanks very much.

[Fenlander]

Re the 6hp outboard choices I'd say consider features, local dealer availability for service/warranty and price then choose which best meets your needs from the main brands as there are all likely to be as reliable as each other in leisure use.

A few thoughts though... The Suzuki is just the lightest at 24kg and has a cylinder capacity 10% greater than the Mercury/Mariner/Tohatsu which some folks like.

The Yamaha is the heaviest at 27kg and again has that slightly larger cylinder capacity. The Gurnard on here has put hundreds of hours on that motor all over the West coast of Scotland and I think he's still very happy with his choice.

The Mercury/Mariner models have the slightly smaller cylinder capacity, are on the light side at 25kg plus have the feature I like a through hub exhaust which Suzuki/Yamaha don't.

The Tohatsu which is virtually the same motor as Mercury/Mariner is given as 26kg plus has the through hub exhaust. For me though a big sway of the Tohatsu is that is seems mostly to come with a 12l separate fuel tank. Even on a small motor I rate this as a useful extra.

[Moorsman]

Thanks all for help ,very useful,my last question,I think I’ll go for zodiac and will need launching wheels ,which type ,also on my present too heavy boat when towing I have outboard on half tilt but on our bad roads it keeps bouncing down ,how can I stop this ? Thanks very much .

[Fenlander]

Launch wheels... just need to decide if you want the type that you take off and back to the car... or the flip up ones. My personal choice for our use is the removable type and the Zodiac own brand are the strongest/best in my opinion if a little pricey.

If you want flip up the best to operate and the nicest quality are made by Trem. They make two weight capacity versions and I always choose the heavier type as they locate on the transom in two places and spread the load.... but you might decide the standard are fine for your new lightweight outfit.

One thing I'm not sure about... is there any kind of lip on the alloy transom that makes fitting the legs difficult... might need a spacer if so... if needed nylon/plastic block best in my opinion.

Zodiac transom wheels... https://shop.chastheboat.co.uk/products/z61161

Trem flip ups... use the drop down menu to see the variants... https://shop.chastheboat.co.uk/products/z61161

Of course you only need to remove two pins to take the Trems off so at their lower prices probably a better deal than the Zodiacs?

Re bouncing outboard on trailer either some sort of stay from trailer to skeg or a packing block held in the saddle area holding it part lifted.

[Moorsman]

Thanks very much for your reply,great ,I have a good idea what I will be going for ,a second hand one would be fine but there never seems to be any about ,when I get one will post with updates,cheers

[Locozodiac]

Motors having non through hub exhaust systems are the old type no matter if being fabricated new. With the through hub ones will have more spare props to choose from if plan maximizing a less pitch prop in the future.

Check if there's Tohatsu 2 stroke motors available in the 6-8-9.8 HP range, if so go straight for the larger one as all three mentioned models weights exact same with equal 170 CC powerheads, will serve you well if plan powering whichever size you choose from while more loaded.

Happy Boating

[Moorsman]

Sorry to be thick but which are the motors with through exhaust type ? And which are the better type ?

[Fenlander]

As I said above...

>>>The Mercury/Mariner models have the slightly smaller cylinder capacity, are on the light side at 25kg plus have the feature I like a through hub exhaust which Suzuki/Yamaha don't.

>>>The Tohatsu which is virtually the same motor as Mercury/Mariner is given as 26kg plus has the through hub exhaust. For me though a big sway of the Tohatsu is that is seems mostly to come with a 12l separate fuel tank. Even on a small motor I rate this as a useful extra.


But don't get hung up on it it's just my personal preference if there are no other features you judge more important. Loco says the non thro-hub are old designs but more accurately smaller outboards never used the thro-hub exhaust system and it is no detriment to those that keep such a system on small HP motors.

As I say look at the balance of features that suit "you" and choose on that basis.

[Locozodiac]

Originally Posted by Moorsman

Sorry to be thick but which are the motors with through exhaust type ? And which are the better type ?

A through hub exhaust system in the ones now in current use in all modern 2-4 strokes motors 4 HP and larger. This type of prop is the one with a hollow middle center as in pic, the other non through hub prop ends in a cone with attached side cotter pin. The oustanding difference is a much better prop thrust due to the exhaust method. The other prop discharges the exhaust under the lower leg and the prop doesn't get any advantage out of it..

Hey Fenlander, why would you like Moorsman to return to the Wagon prop era, it's a real bad advise given just because you like the prehistoric exhaust system ....

Happy Boating

[Fenlander]

Loco please don't dilute Moorsman's thread with your attempts at mild insults inferring bad advice for guidance I've given. You have already misled him over the weights of small alloy hull RIBs in your post #2 giving advice opposite to the true situation.

And now you try to say I'm advising a non thro-hub exhaust. If you read my advice I said I actually prefer the thro-hub style... but if different more important features for Moorsman led him to the other type then there is no problem going for that.

If you look at the websites for current NEW Suzuki, Yamaha and Honda 6hp models none have thro-hub exhausts.

https://marine.suzuki.co.uk/outboards/df6a/

https://yamahaoutboards.com/en-us/ho...5-2-5-hp/6-2-5

https://www.honda.co.uk/marine/produ...s.html#bf6shnu

[Fenlander]

Moorsman apologies I left out Honda in my outboard roundup in post #8. There was no reason for that. They are on the heavier side at 27kg like the Yamaha and have a 127cc engine. If you look at their features they may have something that suits your use/needs.

Please also do not be concerned about alternative prop sizes (pitch) on the non thro-hub models should that be needed. For example Honda do 4 alternatives for their 6hp and Yamaha do 5 for their 6hp. I do not have info for Suzuki to hand but can see at least 4 sizes available on Ebay.

[Moorsman]

Thanks for info ,what sort of pitch should I go for on a 3 mtr aluminium rib ,don’t really know yet which engine I will go for ,from the comments made it seems the through exhaust type better ? ,cheers

[Fenlander]

To be honest I've found on smaller motors they are less likely to need a pitch change than fine tuning 15hp and above motors at higher speeds on the plane.

You need a start point anyway for any changes so get the outfit and just use what's on the motor then see how it goes.

If all other factors are equal then yes a thro-prop type is better but I'd not make it a must if other aspects were more important.

Have a look at this from The Gurnard with his 6hp Yamaha on a small RIB... he never seems to be too distressed due to a lack of a thro-prop exhaust!

https://www.youtube.com/watch?v=N8HwbJ16678

[Moorsman]

Thanks for your reply,I liked the video,I go to Lewis every year so reminds me of sweet memories,I also liked his little canopy’s at the front usefull for the beach .