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Old 10 November 2010, 11:35   #21
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You know very well that on the whole a 2/ rated to 100 will produce more power that a 4/ rated to the same power output, not only in terms of torque but horsepower too.
Errr the horsepower rating is a defined legal measurable number. That's a bit like like saying three foot is longer if you are standing on the platform at Euston! A horsepower is a horsepower, regardless how you generate it!

2-strokes, however, generally weigh less per horsepower produced.

Torque is related to compression, crank offset, gearing........



And how much of it is perception? You plant the throttle lever and a 2- stroke will roar into life with the noise & smell we are all accustomed to. The 4- stroke being an eco friendly machine will do the same thing a lot more quietly, so does it just seem like it's not working so hard?
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Old 10 November 2010, 12:48   #22
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Errr the horsepower rating is a defined legal measurable number. That's a bit like like saying three foot is longer if you are standing on the platform at Euston! A horsepower is a horsepower, regardless how you generate it!
Now you're spoiling the fun, too
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Old 10 November 2010, 12:51   #23
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Errr the horsepower rating is a defined legal measurable number. That's a bit like like saying three foot is longer if you are standing on the platform at Euston! A horsepower is a horsepower, regardless how you generate it!
The point is in "on the whole" I understand that often this is incorrect. For instance the Etec 300 is actually only rated to 296hp; the Suz DF140 is widely regarded as a 128hp; and others too.

What about the Pro-XS optis, or even the HO Evinrudes; the 200HO of which on the dyno comes in at 217hp. A 200HO would blow pretty much any other 4/ out of the water.

My point is that a basic 2/ of the same cubic capacity as a basic 2/ will have more torque, and often other characteristics that make it inherently more powerful.
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Old 10 November 2010, 12:56   #24
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My point is that a basic 2/ of the same cubic capacity as a basic 2/ will have more torque, and often other caracteristics that make it inherently more powerful.
You didn't say that though, did you?

I'll ignore the opportunity to take the pi$$ from your typo.
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Old 10 November 2010, 12:58   #25
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The tech for a DF140 states 103kw max output. Put through a converter, this equates to 138.06970509419hp.
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Old 10 November 2010, 13:03   #26
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The tech for a DF140 states 103kw max output. Put through a converter, this equates to 138.06970509419hp.
Soozook must be harking back to their days of unconventional horsepower motors. Remember the 9hp, 16hp and 28hp motors of the late 70s/early 80s?
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Old 10 November 2010, 13:26   #27
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You didn't say that though, did you?
No I didn't, unfortunately I did not proof-read my answer or else I would have immediately noticed and corrected this flaw. For this I offer to you my most sincere and humbling apologies.

BTW I don't actually understand why horsepower is used as a measure of power. Barring the sake of tradition, anyone care to shed light on why KW/0.746 is used? Obviously KW is a metric measure, but why was HP adopted in the first place?
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Old 10 November 2010, 13:28   #28
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No I didn't, and for that I offer my most sincere and humbling apology to you.
No need to apologise, I was only having a larf.
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Old 10 November 2010, 13:33   #29
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Soozook must be harking back to their days of unconventional horsepower motors. Remember the 9hp, 16hp and 28hp motors of the late 70s/early 80s?
Wrapping 138.06970509419 around the cowl would be a squeeze.
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Old 10 November 2010, 13:39   #30
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Wrapping 138.06970509419 around the cowl would be a squeeze.
....and they'd never believe you, anyway
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