2 stroke vs4 stroke

A friend of mine is starting to look at boats.  What is the big differences between a 2 and a 4 stroke outboard motor.  Basically the pros and cons.  Whats better in everyones mind.  Any info would be great and thanks in advance.

Yes 4's are less noisy and yes they are better on fuel. Couple neg.: weight, they do weight more and that can be a problem on a boat that the transom sits low in the water already. Cost more to purchase and cost more to repair. If your looking for a hole shot the 2's have better low end torque to the bow up and moving. What's real nice about the 4's is no more oil mix.

I've heard that often and from many people, but I never understood the valves to adjust thing.  Why?  You don't adjust the valves on your truck.  3 seasons on my 135hp 4-stroke and 4 seasons on my 20hp 4-stroke and I've never had to adjust belts or valves.  It runs fine....just like the day I brought it home.  Oil and gear lube is all I've done.  Haven't even changed the plugs yet.
 
I have had one problem with it though....I can't hear it running at idle.  I've tried to re-start it a few times....but it was already running.
 
Yes, they are heavy....but most of today's boats are designed for that.  My boat has a motor weight rating.  I think it's 640# for main and kicker.  Yes they are slower, but I didn't buy a speed boat.  If I was concerned with speed, I'd get a bass boat with an E-Tec.
 
In my opinion, it comes down to the boat type you want and how you want to use it.
my choices would be E-Tec for a 2-stroke or Honda for a 4-stroke.

ORIGINAL: Trout About

I've heard that often and from many people, but I never understood the valves to adjust thing.  Why?  You don't adjust the valves on your truck.  3 seasons on my 135hp 4-stroke and 4 seasons on my 20hp 4-stroke and I've never had to adjust belts or valves.  It runs fine....just like the day I brought it home.  Oil and gear lube is all I've done.  Haven't even changed the plugs yet.

I have had one problem with it though....I can't hear it running at idle.  I've tried to re-start it a few times....but it was already running.

Yes, they are heavy....but most of today's boats are designed for that.  My boat has a motor weight rating.  I think it's 640# for main and kicker.  Yes they are slower, but I didn't buy a speed boat.  If I was concerned with speed, I'd get a bass boat with an E-Tec.

In my opinion, it comes down to the boat type you want and how you want to use it.
my choices would be E-Tec for a 2-stroke or Honda for a 4-stroke.

Your truck doesnt run at 6000 RPMs though...

Honda or Suzuki...which ever has the closest dealer for you that should be your outboard of choice...Honda 5 year warrenty Suzuki 6 year warrenty.
 
Changing oil is a pretty brainless feature of a 4 stroke...you have to add oil to your 2stroke oil tank or else you will have no lubracation in your motor...so if you cant remember to change your oil out once or twice a season you probaly will forget to add oil to your 2 stroke and possibly destroy the whole thing.
 
The advancement of synthetics over the years has lead to an oil change maybe once or twice a year depending on how much you operate your boat
 
You still have lower unit oil to change as well in any motor....
 
If your worried about routine practices such as changing oil you probaly shouldnt be around a boat in the 1st place.
 
A fourstroke is the way to go.  Look at a power curve online you will notice that that power ratio with a 4storke compared to 2 stroke is very very minimal and the only disadvantage is mostly due to the heavier motor (4stroke)
 
 

ORIGINAL: Trout About

I've heard that often and from many people, but I never understood the valves to adjust thing.  Why?  You don't adjust the valves on your truck.  3 seasons on my 135hp 4-stroke and 4 seasons on my 20hp 4-stroke and I've never had to adjust belts or valves.  It runs fine....just like the day I brought it home.  Oil and gear lube is all I've done.  Haven't even changed the plugs yet.

there are two types of valvetrains. you dont adjust the valves on your truck because they have hydraulic lifters which are self adjusting by oil pressure. your outboard though like my honda prelude and the civic i had before it has a mechanical valve lash. on the end of the rocker arm there is a screw and jam nut that must be adjusted to maintain a certain clearance between the camshaft and the rocker pad. on honda cars it is .005-.007. as the engine runs that lash eventually goes out of spec. normal wearing and vibration are the cause. your motor will still run with a loose lash, to a certain point. first it will become louder although not always noticable. around that time your power output will start to go down. reasn being is there is a larger gap between the rocker pad and the cams lobe. this results in the overall cam duration being decreased. less cam duration means your valve timing events are starting later and ending sooner. looser the lash gets the more power you loose. eventually your lash will become so bad that mechanical damage to the rocker pads will happen from the cam lobe coming in contact with them at an extreme slope instead of being eased in on the naturally gradual ramp of the cam. those harsh ramp speeds will gouge the rocker pads and you'll end up with a broken rocker arm or severely worn out camshaft or other things.

i would suggest doing the lash adjustment. rocker replacements are a pain and im sure they will cost triple what it would with a car since you have to dismantle almost the entire head.

On my 2nd four stroke rite now, very impressed with both of them.  The first was a 1980 honda 10 horse power.  Still runs good, just wasn't enough for the boat.  The new one has only half a season on it, but quite impressed with fuel mileage on it.  2 strokes have come a long way over the years but i they have done this mainly to compete with the 4 strokes.  I think your going to see this split down the middle for another few years until the epa puts stricter restrictions on motors and then the 4 strokes will shine. The valve adjustments are called every 100 hours, which is probably atleast 2 seasons for me and i'm fishing 3 to 4 nights a week running 5 to 6 miles a night hitting the allegheny river for bass or eyes.  I'm happy i went with another 4 stroke...

I'm not seeing any bashing going on just thought out comments on each style.

W/ a used boat you do have an option; some people purchase the used hull and forget about the motor hanging off it and re-power the hull. Some people purchase the hull w/ the intent to us the existing motor till it dies and then re-power. Others purchase and repair the motor forever w/ no need to question what's the other options of motors.

ORIGINAL: anzomcik

this might seem like a dumb question but is your friend looking at new or used boats? mainly because normally people who buy a used boat do not have much option with there motor, just because there are two kinds of power plants does not mean you can pick and choose, but i might be telling you something you already know. Im just trying to say sometime people get caught up in decisions that have already been made.

This is the way i see this question, you have people that are die hard 2s, and people who are die hard 4s. asking a general question about the advantages of each will not get far because everyone bashs the other style they dontlike.

My two cents, 150hp is 150hp weather its 2stroke or 4 (just an example) any new outboard motor is great and i feel there is not wrong decision. both have maintance just different kind. look at pricing and your buget and pick the motor that suits your friends needs the best, when it comes down to it your friend will be using it and maintanceing it. there is not a wrong answer, have fun

ORIGINAL: anzomcik

this might seem like a dumb question but is your friend looking at new or used boats? mainly because normally people who buy a used boat do not have much option with there motor, just because there are two kinds of power plants does not mean you can pick and choose, but i might be telling you something you already know. Im just trying to say sometime people get caught up in decisions that have already been made.

This is the way i see this question, you have people that are die hard 2s, and people who are die hard 4s. asking a general question about the advantages of each will not get far because everyone bashs the other style they dontlike.

My two cents, 150hp is 150hp weather its 2stroke or 4 (just an example) any new outboard motor is great and i feel there is not wrong decision. both have maintance just different kind. look at pricing and your buget and pick the motor that suits your friends needs the best, when it comes down to it your friend will be using it and maintanceing it. there is not a wrong answer, have fun

He is looking at new boats.  I see your point about everyone having there favorites.  He asked me the question about 2  or 4 and I really did not know. Other than the price.  My boat and motor are old.  Thank you for all the response I will pass all of this info to him. 

CB,
I recall seeing a VTEC sticker somewhere on my motor.  According to Honda's site, the 90, 135/150 & 200/225 motors have VTEC.