Maximum engine power for Tiki31

[Olli Väänänen]

I just launched my Tiki 31 Maija-Liisa, and on the first sail I was met by a policeman on a water scooter.  He congratulated me for the big occasion; it remained a mystery to me how he had known that this very day I was launhcing the boat! Obviously I am living in a small town, where the news spread quite rapidly.

What the policeman said next, was another surprise. He asked for the registration of the boat. In the process on building and launching I had completely forgotten about it. In Finland I have to register any boat longer than 5 meters.

The policeman was very kind and did not fine me or do anything else unpleasant. He just told me to hurry up with the registration. This is what I am doing now.

In the registration form they ask for the maximum power capacity of the boat engine. I have at the moment a small old Volvo Penta 3.6 hp engine, but I am planning to get something in the range of 10 hp, which obviously is about the size used on Tiki31 or Tiki30. But I'd like to register maybe a bit higher figure, just in case something comes up, and I'd find a somewhat more powerful engine (it is not easy to find a used engine with a long enough shaft!).

So my question is: has anyone installed a more powerful engine than a 10 hp on Tiki31? Or what is your opinion about this? I'd appreciate your help, because I think I must hurry with the registration: my Tiki is the only catamaran around here, and I am pretty sure the police will renew their visit in the near future, just out of pure curiosity!

[Bart]

Hi, I use a 9.9 Yamaha high trust, xl on a tiki 30. I think the motor is the right one. 6.5 knots in flat water. 5knots with 5bft head on.
For my taste 15 HP high trust would be the max and a bit overkill.
I think the tiki 31 is a bit heavier? 2 mast..

Enjoy you new boat!

[Bart]

(The high trust version of yamaha is really good. It has a bigger prop and so more thrust in waves and wind ahead)
Regards Bart

[Ian R]

20hp Tohatsu MFS 20C has 27.1" ex- ex- longshaft. I have this one but it's obsolete,  though might be available 2nd hand. I got mine on Ebay.  Downside is it weighs 65kg. When I carry it I have to sit down after. It might be a good idea to allow for a bigger engine if you can get a longer shaft. Standard 10hp longshaft 25" has cavitation in rough pitching conditions in my limited experience (Tiki 31) of 10hp (about 300 miles sailing that one), that's why I have the big Tohatsu and beefed up the sled. It needs 4:1 tackle to raise it, the Wharram design won't lift it. I'm not sure about the angle of the back of the sled as design dictates, the engine is only near vertical on the last hole of the tilt  bracket in my case. Wharram designs are pretty vague and sometimes wrong, I have got quite annoyed with redesigning and trying to correct stuff as anyone who has read my very irritable posts will know...grrr, love the boat though.

[Jose Alberto Garibaldi]

Olli 

Great to hear from you. Leveller has a honda 15. It is reliable, and seems perfect for the boat  neither heavy nor powerless, and in fact wth more than enough power to counter any strong tide and still run forward with authority. . Seems like a good fit. on another note, many thanks for your posts on the steering wheel  - am currently exploring setting a couple, and will post photos if successful. 

Best wishes. 

Jose A.

[Ian R]

PS congratulations on launching your boat, massive achievement.

I had 15hp Honda on order when the Tohatsu turned up, which saved me £2K and added me 2", but had the weight disadvantage as described.

The 15hp seemed the ideal motor for weight and power.

Where my boat is the river runs very fast with little respite and I want the extra hp so am happy with the 20hp motor;  and spent the £2K saved  on wine and women as sailors are supposed to do.