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Old 25 June 2010, 08:01   #1
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Optimax or Tohatsu

When I swap the motor off my newly acquired Gemini 550, budget dictates my engine choice is going to be either a Tohatsu 90 TLDI or an Optimax 90...
Thoughts anyone?
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Old 25 June 2010, 09:50   #2
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Can't comment on those two, but the "conventional" 2-stroke Tohatsus are quite reliable, and having lived through a warranty problem with a friend, the Tohatsu bods seem helpful.

As a thought, could you temporarily de-rate the VRO a bit by adjusting the throttle linkage?

There may be a WOT stop, or a link you could adjust so it doesnlt fully "open up". Other option is your remotes box may have two or three holes in the throttle lever arm on the mechanism. if so, moving the cable end to a hole nearer the pivot will give less throttle cable throw and reduce the thottle opening. Retarding the timing by 10 degrees or so could also work.
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Old 25 June 2010, 13:42   #3
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big weight difference
170 for the opti
143 for the twatsu

dont know current prices
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Old 25 June 2010, 15:00   #4
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have seen the Tohatsu for as low as 5249
and an Optimax for 5439...
I would love to put an Etec on it ... just dont have that sort of money
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Old 25 June 2010, 15:34   #5
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I believe they use very similar injection technology.

Speak to a dealer who supplies / services both and ask their opinion.

Fairweather Marine are dealers for both so should be able to give an unbiased opinion.
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Old 27 June 2010, 03:53   #6
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the weight is quite a difference...
sounds like the Tohatsu is the way to go.
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Old 27 June 2010, 07:31   #7
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I have heard that the Tohatsu has incredibly good fuel economy and excellent reliability too.
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Old 29 June 2010, 11:54   #8
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Quote:
Originally Posted by MustRib View Post
When I swap the motor off my newly acquired Gemini 550, budget dictates my engine choice is going to be either a Tohatsu 90 TLDI or an Optimax 90...
Thoughts anyone?
Get the Tohatsu, power to weight is so much better, the reputation for reliability of the Tohatsu is another big plus.

abc
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Old 29 June 2010, 12:07   #9
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Originally Posted by matt h View Post
big weight difference
170 for the opti
143 for the twatsu
That's 'cos the Twatsoo is a 1.3 litre powerhead, while the Opti is 1.5 litre. The 115hp & 125hp Optis also use the 1.5 litre powerhead, while the larger Twatsoos step up to 4 cylinders.
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Old 29 June 2010, 18:07   #10
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Granted, my opinion might be biased but;

Optimax all the way, cracking engines and have sold hundreds to very happy customers.

You also get 5 years warranty as opposed to a 3 year warranty.

Damien.

PS.

If you have any questions at all on the Opti, then I'm happy to help out.
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