Firstly Ric thanks for your warm welcome and encouragement.
I am Planning to use the vessel around Hervey bay Moreton Bay etc. both funnel water = strong tidal flows.
found the 6hp yammy2stroke lacking when first time out (30 to 40 Km gusts and nice chop in local dam) I am not planning on racing so unless there is something safety wise that I dont know about I am not so worried about the extra 15 kg on the stern (please educate me)
so back to question of gear ratios and why does everyone think 9.9 is too big what is the rationale ? is 15 kg more- really that much more over the previous 27kg motor
In my state the vessel is rated to carry 7people for its length not that I would ever attempt it but even with 3 adults and 2 kids it is a nice stable platform.
I Need a motor strong enough to get me out of trouble and would rather run at low revs than try and punnish one at redline as I drift into the sea wall
I noticed no one has come back with any catamaran hull dynamics in consideration Like why I should not Ballast to the font with a heavy heavy9.9
at the back
so would the 2.08 ratio cavitate madly or would it just throttle the engine
would the 2.42 ratio rev the motors head off or just throw rooster tails while planing on the centre board?
Tug boat eh Toot Toot
Must sleep now