View Full Version : 2 stroke or 4 stroke

19-02-2002, 02:37 PM
I'm leaning towards 4 stroke but would like peoples opinions on reliability comparisons and can anyone see the price being a bit more competitive with 2 strokes anytime soon? Pros and cons?
Cheers Luke

19-02-2002, 02:57 PM
Luke...a touchy subject mate. 2 verses 4?

I am a strict 2 banger man, (later models). Nobody has been able to convince me that the few benifits of 4 bangers are worth the extra $ and the extra weight.

2 bangers are VERY quiet and smooth now with incredible "out of the hole" instant revs and power. 4 bangers are a smoother deal, however, they do not display the jump up charicteristics of the 2`s.

All this is based on under 50hp. I`m not aware of how the larger 4 bangers go.

Later model 2 bangers are equal now in decibals to the 4`s.

My thoughts mate. Now someone will come along with a hole new opposing opinion. Thats cool, each to thier own huh?

Regards, Randall. (The out of the hole fast fella)

19-02-2002, 03:49 PM
Thanks for the reply Randall,
One of my concerns is ongoing costs if something goes wrong- which one is generelly cheaper to fix and am also after opinions on these 3cyl oil injection two strokes. Do the newer two strokes still smoke up as much as the older models? And does anyone know of 2 stroke engines being phased out in Australia. I've heard in USA they are already phasing out 2 stroke lawn mowers to start with. Any truth to any of this?
Cheers Luke

20-02-2002, 06:50 AM
Yep sticky issue. Both have got pros and cons.
With the emission control technology that goes into the new 2 strokes, it would be bold statement to say 2 strokes are easier to maintain then their 4 stroke cousins - it's just not so. Lift the cowling and have a look - whole mess of wires and stuff (tech talk that)

I'm a recent convert to a 4 stroke (50hp Yamaha) on the new rig. Out of the hole it is every bit as good as the 2 stroke 40hp Merc on the old rig, and uses less than half the fuel.
One thing I did notice is the cheaper service cost on the new donk.

My 2 cents worth.

All the best

20-02-2002, 01:52 PM
Thanks Jack,
taking everything into consideration but I reckon if I go with a 4 it'll be a second hand rig as it pumps the initial outlay up a bit. Been scouring the trading post and there are some nice boats in my range. Will let you know of the end decision pretty soon.
Cheers Luke

21-02-2002, 04:27 PM
I believe that you have to ask yourself, What will I be using the boat / motor for ?

If we are idling around haning a lure out the back, you'll head for a 4 banger ???. 4 stroke. ( I thought a 4 banger was a bucks night out with a good ending ) oops !

Out of the Hole, performance is great if you intending racing the beast or buzzing around in the bars.

Sure, cost comes into it. EPA 2006 regs are getting everyone scared in the States.

I never trust an oil injected 2 stroke. Known too many people have failures, No Oil.....No Motor. That's a 2 Banger.

As Jack says, the servicing costs also come into play.

Motors are a personal thing. Good Luck

24-02-2002, 04:22 PM
Still leaning towards the 4. Thanks fellas. BTW I thought getting outa the hole was a bucks night with a bad ending Phil. Thats enough anyway ;D
Cheers Luke

25-02-2002, 04:59 PM
No Luke, a bad ending is not remembering the ending ???

06-03-2002, 08:29 AM
I have a 40 4stroke merc on a quintrex hornet trophy 435 and it has unbelievable economy and speed, both top end and out of the hole. The rig I had before that was a 16foot clarke abolone centre console with a 60 hp Evenrude 2 stroke. Wouldn't go back to a 2 stroke now but they have there place. Still a good motor

10-12-2006, 10:02 PM
4 stroke for me. Quiet idle, no smoke.

11-12-2006, 06:00 AM

To answer some of the comments above.

Emissions regulations means that they will no longer be selling hi emissions motors ( incl lawn mowers) #in various parts of the world. # Eg #Europe , USA # Canada #…

These high emissions motors are chiefly traditional 2 strokes ( carby and EFI)

That means only 4 Strokes and Direct Injection 2 strokes will be on the market in the biggest markets. # #When you look at the actual numbers its scary # #- I give you an example below.

There are no plans to ban any technology (except lake Lenthalls from 2010 – 4 strokes only). # There are plans to have an emissions labelling scheme in Australia starting January 1st 2007. # Have a look at #www.oeda.com.au

An OEDA #3 star motor has a lot lower emissions. #Lets look at a 50 hp #example of emissions #( HC +NOx g/kw/hr)

Honda 50hp #(4 stroke #carby) # # 13.33
Yamaha 50 hp ( 4 stroke dfi) 15.072
E-TEC 50 hp (2 stroke direct injection) #13.44
Yamaha # #CV 50 hp ( 2 stroke #carby) 167.474

That’s right #- the 2 stroke carby is 10 times the emissions. #Actually the example is low (167) # many 2 stroke carby motors are as high as 300, some as high as 600.

What do all these numbers mean in practice? # #In a “typical” hour of running ( 10 mins full speed, #10 mins 75% # etc ) # the traditional 2 Stroke will but out an extra 150 g/kw/hr #or so of emissions ( Mostly HC – Hydrocarbons #- fuel and oil, unburnt and part burnt)

That’s 150 #grams ...# per kilowatt #.. per hour. # #So with a 50 hp #(about 34kw) #the EXTRA #emissions are # 150*34 #/100 # = 5.1 kg #of junk being put into the water and air.

Here is the part that #that will get people grumpy with me # - but I too was shocked when I first worked it out.

If you use a 50 hp 2 stroke carby # that’s the same as using a 4 stroke – and pouring an extra 5 kg of emissions into the environment. # #Picture someone taking a 5 litre pack of used oil and pouring it out at their favourite fishing spot and you get the idea.

Now you see why they have banned traditional 2 strokes in much of the world.

In Australia we have a choice #- and the new labelling scheme gives you reliable data on emissions.

Some 2 tradition stroke fans #will be in denial # #- its is hard to swallow, I know. #

Some will say “ I didn’t know” # #- yep #neither did I . # That’s the reasons we have a label scheme. #So we will all know next time.

Call me if you like #...



0412 111 573

11-12-2006, 07:21 AM
Gotta love resurected threads from 2002 :-X

11-12-2006, 07:59 AM
On going costs have me convinced about 4 S's.
I've gone from 18-22l for the 2S down to 6-7l for the 4S on pretty well the same fishing trip. Won't take me long to clock up savings.
Sure I went from a 25hp 2S to a 15hp 4S but on a 3.7m tinny I didn't need the bigger hp. Never used all the throttle at all on the 2S.
The 15 does everything I want it to do ;D
Oh, and I love the magic little black button that makes the little 4S go. No more chord pulling for this lazy slug ;D

11-12-2006, 09:10 AM
Gotta love resurected threads from 2002 #:-X

Especially from a member registration of Dec 9, 2006 ;D and considering the subject ::) ya gotta wonder ;)

11-12-2006, 10:42 AM
Yamaha have recently told dealers that their 4S no longer require 50 hour servicing that brings them into line with 2S service intervals.

11-12-2006, 07:21 PM
Yamaha have recently told dealers that their 4S no longer require 50 hour servicing that brings them into line with 2S service intervals.

Yep, was told the same by my Suzuki dealer. First service at 20hrs and the next at 100hrs.

11-12-2006, 08:39 PM
Yep new Yammi 60 4 stroke service intervals (10 hours then 100hours)
Service cost seems pretty high to me (10 hours @$269 + parts & 100 hours@ $400 + parts) :o ....... Does this seem high :'( :'( :'(

11-12-2006, 10:02 PM
So whats changed with these 4 strokes to be able to double the service intervals?
Or have dealers been doing twice as many services as necessary?

12-12-2006, 02:43 PM
Yep them bass fish are pretty dam fast ::) Like unless one has a 100mph bass boat AND a holeshot, err sorry maximum holeshot (whatever a maximum holeshot is :-X) then they simply can't call themselves bass fisherman :D

Bugga can only manage 98mph :-* going to have to give this bass fishing away, just not fast enough and the holeshot, just not maximum ;D

Like since when does anybody need an overpowered 100mph canoe to catch mongrel little fish :-? starting to sound americanized ;D

12-12-2006, 06:03 PM
mate got a 2000 40 yammy 2S. had it since brand new. very quiet and some passengers even think its a 4S. Fuel as long as you stay below maximum RPM is brillant. ie. I can get 160km's off 52 litres of fuel. Km's coming off my garmin gps 12 and fuel coming from fuel pump. I remember going into my local etec dealer in townsville asking for a possible trade in price. $10000 for new motor and maybe 1800 for mine. NO CHANCE. Most creek trips cost me 15-20 litres. How can a complain with such figures along with trouble free running to date????? Use to cost me like $180 for a service every 18 months. Hope that helps.

12-12-2006, 09:15 PM
Rod bender,
# # # # # # # # # #Stick with the yammy,mate.I hear you and ETECs dont exactly get along to well together!!!
# # # # # Might be some sort of curse!!

# # # #Cheers Scott