What about this wee beastie?

[Pecheur Anglais]

Would appreciate some experienced SIB users views on this:

https://boatworld.co.uk/boats/boatwo...-350-air-floor

I am after a very lightweight boat to buzz about in, do a bit of fishing, etc. I have read other SIB posts but no mention of the Elling KB 350, I guess its either new to the market or something no one else would go near!

[Fenlander]

http://www.rib.net/forum/f50/any-exp...ran-82353.html

Edit: Oh wait a minute that was you too.

[The Gurnard]

Yup..I agree with your comment on the initial link Fenlander… 30mph from a 6HP ..its all salesman talk..

So dont touch it with a barge pole until the salesman comes clean Pecheur … you will be disappointed if you do

[Pecheur Anglais]

Originally Posted by Fenlander

http://www.rib.net/forum/f50/any-exp...ran-82353.html

Edit: Oh wait a minute that was you too.

Yup, just asking for opinions about the boat from watching the video now, rather than views based on specific experience with the boat, which was maybe unrealistic if too few people have used it.

I have emailed the supplier re trying the boat, but they are a mail order company in the midlands, so a sea trial maybe a long shot.

Without finding any positive or negative feedback on the boat, I'm considering taking a chance on it. Then, if it doesn't meet their advertised performance, take them to task. After all, someone has to try new stuff first!

[Fenlander]

Your call obviously but I’m not sure I’d go to the hassle of buying with the intention of a sale of goods challenge to try and return on basis of not meeting a performance claim which depends on so many factors it would be near impossible to prove.

But I agree someone has to be first to try a new concept. Difficult call.

[jeffstevens763@g]

Expensive for the quality plus bollocks about performance IMO

[Pecheur Anglais]

To be fair, the supplier has responded to my email. He is at the boat show but has a customer in Anglesey who bought a KB 350 and is very pleased with it. He will contact the customer and ask him to take me out. So, we will see!
Comment about quality/price appreciated, although they give a 5 year warranty. Seen plenty of cheaper sibs, but I'm open minded about the performance claims.

[Fenlander]

That will be a good way of finding out.

Here is quite a good test. With a 9.8hp 2-stroke maxed out an average size bloke one-up with an average amount of kit manages 29.2km/h... so 18.1mph or about 16kts. I'd say that's much nearer what you'd expect speed wise for a 10hp never mind a 6hp.

https://www.youtube.com/watch?time_c...&v=dhERqWsBoJo

[ShinyShoe]

Maybe it could do 30kph on 6hp?

Maybe it can do 30mph with 15hp

Then the two become one...

Both Willbe in millpond conditions, light helm, no gear, maybe with a following current.

What do you actually want the boat to do and why do you want new?

[Pecheur Anglais]

Originally Posted by Fenlander

That will be a good way of finding out.

Here is quite a good test. With a 9.8hp 2-stroke maxed out an average size bloke one-up with an average amount of kit manages 29.2km/h... so 18.1mph or about 16kts. I'd say that's much nearer what you'd expect speed wise for a 10hp never mind a 6hp.

https://www.youtube.com/watch?time_c...&v=dhERqWsBoJo

Enlightening video, thank you.

So would you say that's not much different to any similar SIB/motor combination?

[Fenlander]

I think it has the potential to be top end of the ball park if it runs mainly like a cat when on the plane. But that video guy’s experience shows it not to be in the league of their website claim.

My apparent negativity is purely around that website claim and it’s price given the lack of brand establishment in the UK. Other than that it would be great to have a forum tester for the design... you could be that person!

[Pecheur Anglais]

Originally Posted by ShinyShoe

Maybe it could do 30kph on 6hp?

Maybe it can do 30mph with 15hp

Then the two become one...

Both Willbe in millpond conditions, light helm, no gear, maybe with a following current.

What do you actually want the boat to do and why do you want new?

Mainly fishing, plus an occasional blast across the bay, just for the joy of it.

First priority is light for single handed launch on dinghy wheels.

Second priority is fast.

I would be happy with second hand in good condition, but not seen 30mph SIB with 6hp before, even in optimum conditions.

[Pecheur Anglais]

Originally Posted by Fenlander

I think it has the potential to be top end of the ball park if it runs mainly like a cat when on the plane. But that video guy’s experience shows it not to be in the league of their website claim.

My apparent negativity is purely around that website claim and it’s price given the lack of brand establishment in the UK. Other than that it would be great to have a forum tester for the design... you could be that person!

I don't see experience based scepticism as negativity, it just helps to keep my inexperienced eyes open to potential pitfalls and is appreciated.
Once I have as many facts and opinions as offered, and hopefully tried the boat I will certainly post some feedback for the benefit of others.

[chipko]

I’ve seen the KB350 in the flesh both at Boatworld and the Boat Show.
Decent quality lightweight build backed up with 5yr warranty.
Very similar to the bow fronted Takacats so should have similar ride qualities....fast, lively, corner flat with good grip. As essentially a cat design, flat floor mounted high between large tubes, then deck will feel shallow...not a problem but will feel less secure to some at speed in chop.
Not sure how effective the central keel will be. The Takacats are very susceptible to ventilation with some outboard combos...having the prop cupped helps in a lot of cases. I think Elling have added the central tube to stabilise water flow in front of prop....sceptical if this will have any great improvement but shouldn’t hinder performance anyway.
Performance claims are absolute bollocks, do the maths.

[Pecheur Anglais]

Originally Posted by chipko

I’ve seen the KB350 in the flesh both at Boatworld and the Boat Show.
Decent quality lightweight build backed up with 5yr warranty.
Very similar to the bow fronted Takacats so should have similar ride qualities....fast, lively, corner flat with good grip. As essentially a cat design, flat floor mounted high between large tubes, then deck will feel shallow...not a problem but will feel less secure to some at speed in chop.
Not sure how effective the central keel will be. The Takacats are very susceptible to ventilation with some outboard combos...having the prop cupped helps in a lot of cases. I think Elling have added the central tube to stabilise water flow in front of prop....sceptical if this will have any great improvement but shouldn’t hinder performance anyway.
Performance claims are absolute bollocks, do the maths.

Thanks for your comments on the likely handling characteristics, how the boat may feel in a chop and possible ventilation.

I am curious about "the maths". Are there some basic calculations that I could use to estimate performance of boat/motor combinations?

[chipko]

Sorry, based on theoretical max speed for a propeller of known pitch. Formula;

(pitch x RPM)/(gear ratio x 1056) = theoretical speed

So assuming a typical 6hp is fitted with an 8” (generous) pitch prop, max rpm of 6000 and 2.15 gear ratio.

(8 x 6000) divided by (2.15 x 1056) = 21.14mph

This would be the absolute theoretical max for that prop pitch irrelevant to engine power. You then need to apply a slippage factor of anything between 10 to 45% depending on hull type etc.

On a well set up sib 10 to 15% slippage would be very good, so technically around 18mph. I doubt though that a 6hp would have enough grunt to turn an 8” prop at max 6000 revs.

[jeffstevens763@g]

what's the crease on the starboard tube for in the vid

[Fenlander]

Some sibs have a slight pinch point at the baffle location Jeff... if you put a straight edge along the tube... I'd assumed it was an excessive version of that??

[jeffstevens763@g]

Originally Posted by Fenlander

Some sibs have a slight pinch point at the baffle location Jeff... if you put a straight edge along the tube... I'd assumed it was an excessive version of that??

um not seen that before i guess it's the light weight material that makes it more pronounced.

[Pecheur Anglais]

Brilliant, learnt something new! Thanks Chipco