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Old 19 July 2012, 17:47   #11
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Originally Posted by willk View Post
That was your excuse two seasons ago. I'm sure you mean "spouting" this time.










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Old 19 July 2012, 17:49   #12
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Reducing weight is always a good thing, car manufacturers nowadays are constantly trying to shed weight from the bloated machines they now churn out. Light weight means better fuel consumption, better acceleration and better top speed. And you can have all these things combined with the fuel consumption, low noise and smoothness so often associated with a fourstroke...in a two stroke...only with Evinrude Etec
A vote there then for weight reduction and lower noise.

Does that mean that "I.T.R." will be any lighter or quieter this season?
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Old 19 July 2012, 17:57   #13
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Originally Posted by willk View Post
Does that mean that "I.T.R." will be any lighter or quieter this season?
I think ITR and her associated "personages" have been much quieter this year!?

Sproutation has occurred, I concur.

The etec on the other hand...sounds like a flipping diesel generator at idle
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Old 19 July 2012, 18:02   #14
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Power and speed isn't everything, power to weight ratio, though important isn't everything either. The reason your SIB only goes 1mph slower as you add a person is due to the efficiency of the plane..If you keep adding people then there will come a point where if you add one more person then the boat will not plane and so that one person will drop you 5 or 6mph and make you use alot more fuel than without them.

I see from your profile that you have a tohatsu, I am going to imagine it is a two stroke for arguements sake, therefore pretty light. If you were to swap that engine for a four stroke (or any much heavier outboard), for example a honda, of the same power then the number of people you had to put onboard before the boat wouldn't plane would be reduced. The weight difference between the two engines would not be the weight of a whole new person: the reason why it falls off the plane sooner is because the weight is at the back, just where you don't want it to be when trying to plane..

It is the same with these larger engines, and becomes even more complex when dealing with rough conditions. The weight of my hull dry, is "supposedly" around 600kg, with the engine being 230kg ish, it is a significant proportion of the total weight, and anything we can do to reduce that will reap major rewards. Not just in the performance stakes, but more importantly in the handling and "feel" of the boat.

My last boat was a 4.2m rib, but it had a very heavy fourstroke 50hp on the back and so it was very rear-heavy and this caused a very unpleasant ride in choppy conditions, reducing the weight of that engine would have had massive consequences, infact another member on here specifically decided to go for a 40hp two stroke engine over the 50 from the same manufacturer because the weight difference was so large that the extra power would not only have been offset by the increased weight, but the handling would have been ruined too!

But I'm probably sprouting bollocks again...

Edit:



Reducing weight is always a good thing, car manufacturers nowadays are constantly trying to shed weight from the bloated machines they now churn out. Light weight means better fuel consumption, better acceleration and better top speed. And you can have all these things combined with the fuel consumption, low noise and smoothness so often associated with a fourstroke...in a two stroke...only with Evinrude Etec
Thanks for the info. For the record I have a four stroke but it doesn't have any impact on what you have explained. I have often asked people to move further towards the front of the boat when travelling at fairly low speeds in speed restricted areas because the balance of the boat was stopping it planing when it could and increasing the wake (not good on rivers) or they cause it to fall off the plane by moving towards the back. I never made the connection to the effect having bigger engine would have.

btw are Tohatsu TLDI engines any good? I'm assuming they are similar to the the Etec in concept?
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Old 19 July 2012, 18:04   #15
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I think ITR and her associated "personages" have been much quieter this year!?
I always enjoyed Gotchimum. I felt that she addressed the core issues without any embellishment or verbal embroidery...
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Old 19 July 2012, 18:15   #16
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Originally Posted by Turbodiesel View Post
Fantastic engine!!! See attachment for engine weights.
I love the way the chart has been done, great bit of marketing work, makes you think the others are much heavier due to chart and how humans visualise. If chart had been done from 0 to 500 the difference in the weights would not look so extreme.
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Old 19 July 2012, 18:16   #17
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btw are Tohatsu TLDI engines any good? I'm assuming they are similar to the the Etec in concept?
Yes and yes. And the Optimax of course, they are direct injected two strokes although compared to the opti and to a greater extent the Etec, they are falling behind a little in the fuel consumption stakes and only go up to 115hp. Still good engines though, think I've been out on a 50 a few times.

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I always enjoyed Gotchimum. I felt that she addressed the core issues without any embellishment or verbal embroidery...
I don't think Gotchimum can spell embroidery..
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Old 19 July 2012, 18:29   #18
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Interesting that all of them are better than the Opti at 495lbs...
150 Opti?
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Old 19 July 2012, 18:30   #19
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Originally Posted by willk View Post
That was your excuse two seasons ago. I'm sure you mean "spouting" this time.

MattD, if you insist on asking Gotchi insightful and penetrating questions which encourage him to respond at such lengths, I fear that I'm going to be compelled to do something terrible. No, really, I think I would...
I'm confused... hope I haven't said something wrong?

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Originally Posted by boristhebold View Post
I love the way the chart has been done, great bit of marketing work, makes you think the others are much heavier due to chart and how humans visualise. If chart had been done from 0 to 500 the difference in the weights would not look so extreme.
I was reminded of doing GCSE maths for the first time in god knows how many years when I saw that chart... Must have been about 15 when I spent a whole lesson on mis-leading graphs.. of which that is most definitely one.

It's the noise that bothers me with 2 strokes and the service schedule of the TLDI looks a nightmare, the 40HP one is listed in my service booklet... first one after 10 hours!
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Old 19 July 2012, 18:32   #20
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150 Opti?
You're right...150 only 431lbs... my mistake..
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