Ribeye 2.6 tender

[bosun]

Hello all.
I have bought an ultra light weight alloy hulled 2.6 metre ribeye rib as a tender for my yacht in Greece.
Its rated for a maximum of 6hp so I bought a new 6hp fourstroke tohatsu.
With just me in it it will plane (eventually) but two up it won't.
The ventilation plate is about one inch below the bottom of the transom and there is no easy way to get it higher.
I've played about with the engine angle to no avail.
The prop pitch seems to be about right as with only me in it it will hit max revs.
So my choices seem to be
Doel fins
Trim tabs
A bigger two stroke engine (so as to be a similar weight to the tohatsu.
My other rb is a 5 metre humber destroyer with a modded 90 yam twostroke on a jack plate , I built the engine etc so I have a fair idea of how these things work.
Have any of you tried trim tabs on a little low powered rib tender like mine ?
Or doel fin type fins ?
I know what I really need is a twin cylinder ten horse two stroke but that the most expensive option !
Advice appreciated.

[Tim M]

If try a pair of Doel fins first - cheap and easy

[Sutty]

I have got the 2.8 version with a 9.9 Mercury 4 stroke and it takes a bit of effort and weight distribution to plane with 2up. I don't think whatever you do it will plane with a 6hp with 2 up. I hope I am wrong.

[bosun]

I think you are right
I've been googling and an eight horse twin cylinder two stroke yamaha weighs the same as my tohatsu six.
I saw a much bigger and heavier tender than mine pop straight up on the plane last night with a 9.9 yam on the back, with two largish people and a great dane in it !
I think its the way the power comes in with a twin cylinder two stroke ?!

[beamishken]

We have a 2.8 rib eye tender and originally had a 5hp yamaha and it used to just plane with 1 up we then switched to an 8hp 2 stroke yamaha and it just gets up on the plane with 3 people in, once over the hump its fine but a bit of effort getting up in the first place I'd imagine your problem is the short hull with little to plane on. A set of doel fins may well help to give you more lift and get you over the hump