looking for quick SIB 30 knots+

[spainman]

Good Evening to all.

I am looking to by a quick SIB, and i would like that the si have to reach 30 knots.

The Motor I have I will use it it is an Parsun 60 Hp 4 Stroke.

I am looking something about 4.70- 5,30 meters.

My options at the moment:

Bombard Commando C5

Zodiac Milpor FC 470

Zodiac mark IV

some other sugestions in this size ???

Will it be posibel to reach this speed ?

[mick]

Zapcat

[Max...]

Has to be a SIB?

[Steve509926]

Have you given up with the 6 metre sib you had/have?

[spainman]

It must be a SIP.

and my current one will never reach the 30 knots

[mick]

Can’t imagine wanting to do 30 knots + in Sib to be honest especially with the waves the med throws up

[TmMorris]

Your issue is always going to be the wetted area of the SIB design. Big drag. And the bigger the outboard the bigger the hull needed so your drag just keeps going up.

You should find something that will get towards 30 knots but frankly you are ultimately seeking to defy some pretty basic physics again. And that's before you consider the physics of the weight and torque of a 60hp engine hanging off the back of a long, wobbly, all rubber boat with little compensating mass, limited torsional strength as well as no real traction in the water.

Just get something with a hard hull to take that engine.

[Pikey Dave]

I had a 30kn SIB once, I swapped it for Lord Lucan’s pet Unicorn.

[Quicksilver mike]

I measured 47 kmh which i believe us a touch over 25 knots on my Quicksilver 380 in the sea with a mariner 25hp 2 stroke. 1 person on board

I have measured 53kmh on a well known river in London with the tide 2 people on board with my avon searider yamaha 40hp 2 stroke.

Both measured on the same Garmin Device

[Max...]

One of the new breed Aluminium hulled lightweight RIB (ARIB? ) - say 4m or 4.2 with a 30hp should be good for 25-30 kts I guess? I'd ditch the parsnip 60 and go smaller.

[mick]

Originally Posted by Pikey Dave

I had a 30kn SIB once, I swapped it for Lord Lucan’s pet Unicorn.

That’s a winner

[SixtyNorth]

Gemini Dive 470 or 530? Or, if willing to go a little smaller, the Gemini GRX420.

[HDAV]

Got to ask, why 30kn if you want to go fast a sib is not the answer

I’ve done 70mph on the water, it’s on of its glass it’s good but anything else isn’t pleasant…..

There is always someone with a faster, bigger boat.

[jeffstevens763@g]

Personally I think you will have to go tunnel hull to get that speed less drag OMO

[HDAV]

Originally Posted by spainman

My options at the moment:

Bombard Commando C5


some other sugestions in this size ???

Will it be posibel to reach this speed ?

Looked at the spec for the bombard C5

Outboard Data

Shaft Long
Max recommended power (Hp – kW) 40 – 30
Max power allowed (Hp – kW) 60 – 45
Max weight engine allowed (kg) 128
Max speed (Km/h – Mph) 60 – 37

[HDAV]

The FC470 doesn’t list a top speed on the spec sheet

Weight empty : 125 kg up to 146 kg (depending on the floor option) – 276 lb up to 322 lb

Max pax (Cat.C – ISO 14945) : 10

Max payload (Cat.C – ISO 14945) : 1350 kg – 2976 lb

Max power : 60 hp – 45 kW

Performances : 22 knots (40 HP, 660 kg payload)

[beerbelly]

zodiac futurer fastroller on them lift tubes .dont know if you can get one to use a 60 on but i had one with a 25 yam and it went like a rocket

[Roflhat]

Definitely either thundercat/zapcat/surfcat/GRX420 style or possibly a Futura

[spartacus]

Used to have a Zodiac MkIIC GT (aluminium floor boards) with a Yamaha 25hp 2-stroke. In its day it was fast, (back in the 90s) and perfect speed to weight ratio with two-up. A lardy 4-stroke 60hp you're looking at 5m length, but the hull design will be unforgiving in anything but flat calm.

Anyone knows about speed then Roflhat's suggestion is a Thundercat or Futura, etc.

[spainman]

Hello to all,

And thank you for so much ansers.

I have also written a Letter to Zodiac Milpro in Spain and they recomend me the Mark IV and told mit it will reach about 32-34 Knots with my Parsun 60.

So I will have a look and be saving money for this.

The Bombard Commando C5 is also on my list.

Gemini has too much waiting time for a new boat.