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rojac
23-06-2006, 06:36 PM
That can be be fitted to a 12' dehavilland tinny.

cheers

rojac

bungie
23-06-2006, 07:18 PM
Mercury make a 250hp you could fit. Dont expect the boat to float, but you could fit it ;D ::)

thesimmos
23-06-2006, 07:28 PM
Probably around a 30 or 40hp

Chimo
23-06-2006, 07:30 PM
Rojac

Re HP
Aust Standards issued AS 1799 that is supposed to be in place from early 2005.

It includes a formula to work out the max HP for a boat ie

Length x Max waterline beam at transom x 16 minus 67 x 1.34 = Max HP

Aust Standards also apparently requires that a course be set out with bouys and the boat be tested by operating at full speed and then it has to perform a 90 degree (rt angle turn) within a set distance. (presumably without tipping over!?)

A guy called Rod Henderson wrote this info up in a mag I read so I'm just passing it on.

Can you do the test on the Gold Coast broadwater, I'd like to watch!

Good luck

Chimo

rojac
23-06-2006, 07:42 PM
Just curious as to settle a difference of opinion, I thought that 8hp would be the go as it has very little freeboard, ie when sitting/laying in the front you can wash your hands over the side without getting up however the owner has a 15hp on it.

chuss
23-06-2006, 07:47 PM
Or go Yam or Suzy 300, but would need a 4m floating pod on the rear :-X

thesimmos
23-06-2006, 07:50 PM
depends what you want to use it for.. anything less than a 20 would be more for a tender..

fishn-ads
23-06-2006, 09:43 PM
All the old 12 footer use to have 9.9hp or 15 hp it's got more to do with area of boat in water then anything to do with freeboard. Look at some of these new 18 ft bass boats they have 6 inchs of freeboard and 150hp +.

Blackened
23-06-2006, 11:27 PM
G'day
I have a 12' tinny with relatively low freeboard. Nothing wrong with my 9.9 on it. I'd say a 15max hp for yours, and that's enough.
Dave

morefish
24-06-2006, 12:23 AM
G'day
Have to agree with Blackened 15 HP should be sufficent, I only have an 8HP Mariner on my 12 foot tinnie and allthough a little slower on take off and the quater mile, it plains fairly quickly with two overweight fellas in it.
Cheers
Paul

flotsom
24-06-2006, 10:26 AM
rojac,

i have owner 3 de-havilland seabirds, love the boat, learnt to water ski behind one. everyone i have owened i have put a 30hp motor on it, i have allways removed the forward steering and windscreen, fit a 30 tiller, 1st was a evinrude, it was by far the best, then a merc 30 "LITE" (tohatsu) fast but nearlly shook the boat apart, then whent to a honda, smooth and no fuel.

have fun.

F1SH_BOY
24-06-2006, 06:43 PM
10-30 hp

phewy
24-06-2006, 06:54 PM
Or go Yam or Suzy 300 #:-X


pfffffft............Put black on the back! #::)

lippa
25-06-2006, 01:11 AM
were honda on the market when ya owned that weapon, flotto? ;) ;D ;D

cheers


lippa

flotsom
26-06-2006, 12:46 PM
course they where lippa, this boat caused you some greef, also taught you to ski, for the follows of this thread 12ft de-havilland, safely to moreton and back numerous times. great adventures.