Since this the campfire chatter area I have a question.

[catfish]

sounds like i need one not only in my boat but everything . 20yrs before i would have to buy another one. :wink: only sad thing someone will reliaze they are lasting to long . they cant make no money like that . they will be like vehicles and everything else then made cheap or out of plastic. :cry:

 

[Kayak Jack]

Damned batteries will outlast most of us geezers! Nullifies most of the benefit.

 

[hairymick01]

I am With Dave on this one. A small skiff like a UJ bayou jobbie with a bow mount leccy. Ideal for here.

 

[woodman]

Since this is geared toward small boats..And I have both a trolling motor and a 7.5 outboard I go with the silent runner...and when it is windy and trying to hold the boat steady while drift-fishing I wish I had one mounted ..instead of just the paddle......(But just more stuff to load..then you got to have hands free sterring..and on and on...) I guess that is why I am building a fleet of watercraft????Or is it I'm hooked on building boats?? :?

 

[Kayak Jack]

<SNIP> Or is it I'm hooked on building boats?? :?

Hopelessly and helplessly - you are sliding down into the hallowed halls of sin. WHEEEEE!

 

[swampwood]

I voted for a gas outboard.
They are alot lighter compared to a trolling motor and battery, very reliable (depending on brand) and less hassle.
The 4 cycles do not burn alot of gas and are pretty quiet.
Chuck, these are sold in your state:
http://www.ioutboardmotors.com/index.html
Check them out.

 

[Kayak Jack]

Those are nice looking engines. I'm a bit surprised at horsepower for displacement, pretty low. Maybe they're a low RPM engine?

 

[oldsparkey]

I voted for a gas outboard.
They are alot lighter compared to a trolling motor and battery, very reliable (depending on brand) and less hassle.
The 4 cycles do not burn alot of gas and are pretty quiet.
Chuck, these are sold in your state:
http://www.ioutboardmotors.com/index.html
Check them out.

Yep...727 area code is over on the west side of the state , the Clearwater area.
2HP , 20 pounds weight and 100 pounds of thrust for a 4 cycle engine. That is lighter then just a trolling motor forgetting the battery that is needed to make it go.
It reminds me of the old Mighty Mites ( 2 cycle motors ) that use to be on the market for lightweight boats.

 

[Kayak Jack]

<SNIP> 2HP , 20 pounds weight and 100 pounds of thrust for a 4 cycle engine.

I noticed that the 2 hp 2-cycle engine is rated at only 80 pounds of thust; that's curious. Same horse power would be expected to produce the same thrust.

 

[Wannabe]

<SNIP> 2HP , 20 pounds weight and 100 pounds of thrust for a 4 cycle engine.

I noticed that the 2 hp 2-cycle engine is rated at only 80 pounds of thust; that's curious. Same horse power would be expected to produce the same thrust.

Torque.
Bob

 

[Kayak Jack]

Torque and RPM = horsepower. Both engines are rated identically in power production. I don't think that's the answer, Bob. Prop pitch may not be well balanced to the power curve of the engine, maybe.

 

[jdupre']

Jack, torque is the actual force as measured by a machine (dynamometer). Horsepower is a measure of work done over a certain amount of distance in a certain amount of time. It's the result of a formula. Diesel tractor engines are skewed towards torque. They don't necessarily have to move things fast ....... they just have to MOVE heavy stuff. Automobiles need to be able to move things longer distances in a shorter time. They are skewed towards horsepower.

According to the formula, elephants don't have a lot of "horse" power. They definitely have torque (power).

Joey

 

[Kayak Jack]

You're right, Joey. One horsepower is 550 foot pounds per second. If you reduce torque, you have to increase RPM to get an equal amount of power. And vice versa.
I suspect that they may be over rating the 2-cylce engine at 2.0 hp, since no one has ever under rated an engine.
Equal horsepower should produce equal thrust, whether is comes from 4-cycle, 2-cylce, gas engine, Diesel, jet turbine, electric, steam, a water wheel, a windmill, or hot air like we produce on here. One horsepower is one horsepower.

 

[jdupre']

You're right, Joey. One horsepower is 550 foot pounds per second. If you reduce torque, you have to increase RPM to get an equal amount of power. And vice versa. "
********
Yep, that's it. If you REDUCE torque ( where thrust comes from) you have to increase RPM. If you reduce RPM, torque has to be INCREASED to make equal horsepower. Two engines producing identical horsepower can have a two or even three-fold difference in the amount of torque they put out .
*******************************************
"Equal horsepower should produce equal thrust, whether is comes from 4-cycle, 2-cylce, gas engine, Diesel, jet turbine, electric, steam, a water wheel, a windmill, or hot air like we produce on here. One horsepower is one horsepower.
********
Horsepower is not force. Torque is force. Horsepower is just the result of force over time and distance.

Example: Sven weighs in at 320 muscular pounds. Olle is 150 dripping wet but he's quick. Object is to each move one stack of bricks from one side of the barn to the other. ( work over time and distance = horsepower). Both guys accomplish the task in exactly the same time frame ( same horsepower) BUT......it takes Olle 3 trips to move the bricks and big,bad Sven gathers them all up at one time in his huge arms and slowly walks them to the other side of the barn in one Herculean effort. Same bricks, same time, same distance..................... Who's got the most torque?

Joey

 

[john the pom]

Oh gawd not another torque fest. Thought that was what gov'ments were for. :mrgreen:

 

[Wannabe]

Oh gawd not another torque fest. Thought that was what gov'ments were for. :mrgreen:

Jonn, You can get a little of everything on here.
Bob

 

[Kayak Jack]

Ya may hafta read really close there, but Joey and I agree and are saying the same thing. (Sven however, may not know that.)

 

[tx river rat]

Mercury out board motors were famous for being the fastest and holding the most speed records until someone figured out they were rating the horsepower at the prop and all the rest were rating at the power head . These two motors may have the same thing going on ,lot of claims are made when folks are trying to sell something.
True horsepower is just that but there are some differences in how they put that to the load
Having to work within a power band makes a lot of difference ,look at motor cross bikes , they have very little power at low rpms and have tremendous power in a very narrow rpm range.
You have to learn how to race them staying within that band of rpm, these or 2 strokes.
The 4 strokes dont have that super spot they have power all the way thru the rpm range plus they tend to weigh more so that takes away horse power.
Diesel trucks are low horse power high torgue engines low rpm
Straight or inline engines are the same way heck of a lot of torgue but low horse power . v engines more horse power at higher rpms less at low rpms.
Look at the curve on a v 8 engine low rpm low horse power , you get high horse power at 4000 plus rpms.
Airplane engines or airboat engines is another deal , a lycom engine with 150 horses will out preform a chevy engine that has 500 horse power
Like the boats they are very job spacific.
Ron

 

[Kayak Jack]

Where on the torque curve and power curve they peak is less a function of whether an engine is a 2-cycle or 4-cycle or cylinder layout, than on internal design of the engine. Ratio of stroke to bore is a big determiner, carburetion or fuel injection timing is another, valve timing (placement of intake and exhaust ports on a 2-cycle) is another, ignition timing is another, volume of air flowing into and out of an engine is another (turbo-charging makes a large difference in any engine), and weight of flywheel is another. Simply increasing the weight of an engine's flywheel can significantly change the torque curve to a lower RPM range. If the other design features of the engine - valve timing or breathing, compression ratio, ignition timing, etc. are not in sync with that RPM range, it may harm an engine's performance. It can also "improve" its performance, according to where the user wants the engine to perform its best.

Ron has a good point about where the power is measured - directly at the engine or somewhere later down the power chain. One horsepower is 550 foot pounds per second (ability to lift 550 pounds straight up in one second).

 

[tx river rat]

One horsepower is 550 foot pounds per second (ability to lift 550 pounds straight up in one second).
Thats true Jack no argument there.
But there is more to it than that Peterbuilt diesel engine 380 horse.
Dodge Hemi 390 horse.
With the Pete I can pull 80,000 lbs 80 miles an hour all day and you would be lucky if you untracked 80,000 lbs behind the Dodge and there is no way it will pull it 80 miles an hour down the highway.Now the dodge has ten more horses than the pete and will run faster with a load
How do you explain that?
There are a lot of variables out there on engines and horsepower is not a true sense of the kind of power you can generate to do a job.
Another little note about the outboards and trolling motor .
All electric trolling motors I know of here in the states are geared for a 5 mile an hour top speed
now I am not sure about the outboards .
Ron