A Photo & Discussion Forum for Wharram Design Enthusiasts
Hi, hoping I can get some feedback on the performance of 8hp 2 stroke Yamaha motors for a Tiki 30. Currently we have a Honda 10hp 4 stroke but unfortunately here in Singapore there is no Honda outboard dealer. Backyard outboard mechanics don't want to touch because it is too difficult to get parts, I've been getting parts from New Zealand whenever I go back for a visit.
There is Yamaha dealer here and initially I was going to order a 9.9 long shaft 4 stroke until someone suggested looking into a 2 stroke because; 1) Lighter 2) easier to service, simple compared to a 4 stroke 3) significantly cheaper 4) can have a charging unit 5) potentially similar power output but delivered differently. The key negative is the additional fuel consumption.
So, before spending any money I thought I'd ask the group to share their experience, recommendations, and thoughts. Particularly interested hearing from people who've had an 8hp on their Tiki 30. Other brands with representation in Singapore are Tohatsu & Suzuki so if you've had experience with those brands I'd appreciate hearing. Thanks in advance of the advice.
We have a Tiki 30 with a 8hp longshaft 4 stroke (I think the yamaha) and are very happy with it, in particular because it has a high thrust prop. The Yamaha 9.9hp is apparently a bored out version of the 8hp. The big advantage of the 4 stroke over a 2 stroke for us is fuel consumption (there is a limit to how much you can easily carry) and the lower decibels which make it easier to hear each other when manoeuvring under power. The high thrust prop can stop the boat very quickly which is useful as you need to keep up a reasonable amount of speed to maintain manoeuverability. The only problem we have had in the 10+ years we have had the boat is the seals on the carburettor failing which was apparently caused by the additives that are in petrol, it is advisable to run the carburettor dry.
I use to have a t 30 now I have a t38. I had a 2 stroke Yam 8hp but it got stolen which was a blessing as I then replaced it with a Yam 9.9 long shaft. These are excellent motors and have two on my t 38 and are very happy with them. However if for some reason I needed to replace one, I would replace with electric.
If I were you would get my head around the motor you have. Keep getting any parts from nz and use youtube as your teacher to learn. You have a good motor there. If I was going to replace it I would seriously look at electric. I would n't go two stroke now. Four stroke are quiet, no oil slick on the water like the two stroke. You can get pull start or electric.
The 8 hp was adequate but only just . The 9.9 has plenty of power for the occasional burst you need. quite a big difference between the two.
Many thanks for your replies. My biggest obstacle to keeping on with the Honda is my total lack of mechanical knowledge and I can't find any outboard courses in the region. Still some good feedback, thanks again.
Have been using 9.8 Tohatsu 2 stroke long shaft for 5 years never had a problem. Very light , rugged and inexpensive motor.
Hi - I have a Pahi 42 and now have two Yamaha High Trust 9.9s of different vintages - one is an old white one (1990s..), the other brand new. Originally when I bought the boat she just had one Tohatsu 2-stroke 18hp which was pretty reliable (until last year!) but had no real power to push the boat. It was too high reving. I don't believe you can just add a "high thrust" prop to a regular motor - the gearing is actually different in the high thrust models. The new motor is very quiet compared to the older one, but possibly doesn't have the same "kick". For servicing and maintainence as has been said there are many videos on YouTube - just find a similar outboard from your manufacturer, the principles are the same for all. Good luck!
Hi Nigel thank you for posting with an interesting issue.
I'm building a tiki 30 and placed an order for a 9.9 yamaha hi thrust but must specify the stem length I want.
they have short, long and extra long , can someone share experience on this.
The dealer told me that all outboards have same dimensions for the three shaft lengths.
go extra long. I used this on my previous t 30 and found it great. Found the 9.9 fine too.
Hi Pablo, we ended up buying the Yamaha 9.9 with 25 inch shaft length. Very impressed with the motor, it feels like it has more low end power than the Honda, combination of different gearing & high thrust prop I assume. We brought the electric start as we also wanted the charger but that doesn’t come with a rope start fitted as the Honda did. I like having the option of rope start in case I flatten the batteries which we did once over a couple of days in cloudy weather at anchor running a portable fridge. Check with your dealer as it may be an option to have both electric start & pull cord start. They do provide a rope that requires cover off etc to use, probably no big problem, just my personal preference.The only thing I need to change is the height of the motor as the angle when up is greater than the Honda and it kicks up a lot more water off the prop. Obviously not an engine issue and easy enough to fix. Good luck with the build.
Many thanks to Nigel and Brett for your prompt replies !!
Your answers make me feel better in taking this decision. My friends who are helping me asked
to wait until we have the boat together to double check but I profited for winter prices
for engines sails and dinghy and the saving is there.
I will go with the extra long then. Apparently the extra long shaft in principle is recommended also by the
designer noting it helps keeping the engine as far as possible from the water. You can adjust longer
(hatch permitting) but too short a shaft is a dead end.
Thanx a lot to both.