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  #1  
Old 03-05-2011, 06:49 AM
Dr. Peter Dr. Peter is offline
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Lightweight high-power single cylinder outboard

What is the lightest weight highest power single cylinder outboard out there?
Peter
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Old 03-05-2011, 08:37 AM
michael pierzga michael pierzga is offline
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Dont know...but a high power to weight ratio 2 cylinder is the Yamaha 2 stroke , 8 hp . Good motor...they are the prefered engine for small yacht tenders

You might have a look at this site..

http://www.outboard-engine.com/engin...p?recordID=231
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Old 03-05-2011, 01:15 PM
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PAR PAR is offline
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There's a reciprocating point of limited returns if you will, on spinning engine parts. I've seen single lung, 15 hp engines that could be hot rodded to over 30, but their life span was measured in how many yards or minutes they could run before spitting parts through the engine cover.
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Old 03-06-2011, 09:02 AM
Eagleburger Eagleburger is offline
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A single will shake a lot too.
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Old 03-06-2011, 06:58 PM
Dr. Peter Dr. Peter is offline
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Too heavy and too far away

Quote:
Originally Posted by michael pierzga View Post
Dont know...but a high power to weight ratio 2 cylinder is the Yamaha 2 stroke , 8 hp . Good motor...they are the prefered engine for small yacht tenders

I have an 8 hp of the type you mention which I use on another boat. It is a great engine in my opinion.

The background to this query is that the Yamaha seems to hang an awful long way away from the transom on the outboard bracket on my newly acquired trailer sailer. It's too heavy. I wanted something smaller and lighter - hence my equiry about a single cylinder - lighter motor.
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Old 03-09-2011, 08:34 PM
DCockey DCockey is offline
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We have a Mercury 6 HP which is reasonably light at 55 lbs/25 kg. It's primary use is as auxilary on a 20 foot, 1 1/2 ton sailboat which it will push nicely at 5+ knots. It's also compact, smaller than the 4 HP, 2 stroke, Evinrude it replaced. The same engine is also sold under the Mariner brand.
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Old 03-12-2011, 07:23 AM
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pistnbroke pistnbroke is offline
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if its a mercury or mariner its a Yamaha
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Old 03-12-2011, 08:31 AM
DCockey DCockey is offline
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Quote:
Originally Posted by pistnbroke View Post
if its a mercury or mariner its a Yamaha
The Mercury/Mariner 6 HP 4-Stroke is a completely different engine than any Yamaha engines.
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Old 03-12-2011, 11:06 AM
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pistnbroke pistnbroke is offline
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my brain slippage..... I should have said its a Tohatsu. Many of the slightly older Mariners were in fact Yamaha but Tohatsu are now supplying many manufacturers world wide
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Old 03-26-2011, 02:19 AM
Dr. Peter Dr. Peter is offline
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Saw a DT4 2 stroke Suzuki at my local Yamaha dealer for half the price of a new motor. Any opinions - based on experience about these?
Peter
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  #11  
Old 03-26-2011, 02:55 AM
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pistnbroke pistnbroke is offline
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Ask the dealer for a water test on your boat ..if its ok buy it ...bit like a sheila ..give it a test run ..sometimes second hand runs very well.....ha ha
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  #12  
Old 04-11-2011, 08:00 AM
Dr. Peter Dr. Peter is offline
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Mariner 5

A friend had a 5hp 2 stroke mariner which I have seen in action. Good price. Any thoughts?
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  #13  
Old 04-11-2011, 08:28 AM
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pistnbroke pistnbroke is offline
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Isthis the one ???? most of the slightly older 2 stroke Mariners are yamaha like this one light at 21 kg
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Lightweight high-power single cylinder outboard-hpyamaha.jpg  
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  #14  
Old 04-11-2011, 08:47 AM
powerabout powerabout is offline
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tohatsu are still selling 2 strokes
on average 10+kg lighter than their 4 stoke equivalent
__________________
Boat builders are not necessarily Boat designers who are not necessarily Engineers who are not builders who are not designers.....
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  #15  
Old 04-11-2011, 10:05 AM
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pistnbroke pistnbroke is offline
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Read a recent reviw of some 4 strokes 9.9 s .....bollard pull /max speed etc ..They then got a 25 year old 2 stroke 9.9 not run for 10 years and compared it ......faster and more bollard pull ...but used more fuel .........what you put in the tank comes out the prop ....
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