Decisions..2007 Yamaha 2 stroke or 2018 Tohatsu 4 stroke

[tiltrider1]

Didn't mean for my last post to sound so harsh. Was not directed at anyone or ment to insult any one.

[smitty477]

Originally Posted by Shrew

I raced with a buddy in identical ribs. The dinghy I was in had an 8HP 2 stroke Johnson (it might have even been a 7hp). My buddy had a 9.9 Merc 4 stroke.

Off the line the 2 stroke was on plane and clearly had the hole-shot. I was able to very quickly pull away. Within minutes I had the 4 stroke merc by a HUGE lead (50+ boat lengths). So much so, I dind't bother looking back again. The race was about 1-1.5 miles (We were travelling from point A to Point B and decided to race for fun). About half-way there, the 4stroke merc passed me. I eventually lost sight of him.

The two-stroke definitely had the hole-shot and over short distances was a sprinter. The top end on the 4stroke was much higher and over time and distance crushed the 2 stroke.

I do think there are variables at play. However, not enough to change such a lopsided outcome.

"I do think there are variables at play. However, not enough to change such a lopsided outcome"

Prop pitch , prop type, prop condition, trim angle, mounting height of outboard.
Any one of the above can easily change the performance of the same engine no matter what type it is.
With a couple of these in play you can get a 20% difference in top speed with the same engine.
I know only because we have baselined these on a few RIBS and then varied the items to get a best fit for the use.
Most folks do not even pay attention to some of these but they all make a large difference.

[Larry M]

With a 20 or 25 hp engine on 10’4” rib, you’ll be able to water ski behind it.

[smitty477]

Originally Posted by Larry M

With a 20 or 25 hp engine on 10’4” rib, you’ll be able to water ski behind it.

Not quite - but with a 12.5 RIB with a 40 hp it starts to become possible.

[Baker]

Originally Posted by Ski in NC

I'd shop for a 15 Yami two stroke. Little critter with way plenty power for a dink. Over that in hp and it's overkill.

I am the proud owner of a 2010 model of one of those....the last year they were sold here.

[helm]

You might look at the Suzuki 20, we have one on our Caribe MVP 10. It has really been a great motor

[High Wire]

The Yamaha owner manual for a 25 2-stroke 15” shaft rope start says 106#.
60# two stroke?? Maybe an 8 hp from long ago.

[Nomad Willy]

Like Smitty says ... many other factors. Variables.

I don’t know why 2s smoking would even be mentioned. I run 40-1 dino 2s oil and only at startup do they smoke. Like an FL .. actually much less and lighter color.

But the mixing is something else to do kinda like ya take off your pants to have sex and I’ve never heard anyone complaining about that.

Where to store the gas is a problem but 2s/4s don’t matter.

Archie,
I think my 6hp Johnson and 8hp Yamaha are both very close to 60lbs.

[smitty477]

Originally Posted by High Wire

The Yamaha owner manual for a 25 2-stroke 15” shaft rope start says 106#.
60# two stroke?? Maybe an 8 hp from long ago.

Exactly - here is the manual , page 42 has the specs.

https://www.yamahapubs.com/outboard_...8626-06-93.pdf

[SoWhat]

I would never exceed rated hp for RIB. (20hp)
I would choose quiet reliable easy to maintain 4 stroke.
I would opt for new engine with warranty over used engine if budget allowed.
I would consider used 7 or 8 year old 4 stroke priced in the $1000 range if budget didn't allow new

[High Wire]

Originally Posted by Nomad Willy

Archie,
I think my 6hp Johnson and 8hp Yamaha are both very close to 60lbs.

Agree.
To the OP
My vote would be a new four stroke. My size limit based on what I could carry, and what my wife could pull start.
Other food for thought. A 25 hp 2 stroke will go through a 6 gal tank PDQ. Who needs the hassle of lugging fuel tanks around and mixing oil?

[Andy G]

FWIW, I have just gone through this. We needed to repower our 10' RIB. We had a 15 hp Yamaha. which worked very well on the boat but eventually developed some pretty terminal issues. So the hunt was on for a new engine.

I liked the simplicity of two strokes and as weight was a big factor, I steered away from four strokes. I finally settled on a 15HP US Mercury model over another Yamme, mainly because it was a little lighter and also it has the gear change on the tiller handle. This is a really handy thing to have. Also I have found the Merc is better just running around on idle than the Yamme was.

[WhitePelican]

LOVE my 2008 Yam 25 2.strk !!
Seems like good price on yours, but not up on pricing. My Yammer has been trble.free, burn only non-oxy 91, NEVER cheap out and buy the low.grade ethanol crap! With the money you save you can put on a SS prop, $250. Like mine alot.
Go for the Yamaha !!

[GEOO]

I have a 2005 25 hp Yamaha 2 stroke and a 2017 efi 20 hp Suzuki.

The Yamaha has way more power, Can get on plane with extra people on board, pull a knee boarder, etc.. can lay down and be stored in any position. Needs spark plugs and carb cleaned every year.


The Suzuki has less power, need to store certain ways or sides, less maintenance, clean, idles way better.

If you need power to carry extra weight or pull water sports, then get the Yamaha, other wise the 4 stroke is easier, cleaner.

Good Luck!!

[WhitePelican]

Re: 25 Yam, was also able to get our West Marine Rib5 on plane w 4 people, no prob; just as a test.
Our dinghy works best as a 2.seater, too crowded w 4

[dotgone]

I am 99% sure you have the weights reversed. In any case I like the yamaha and you should be able to negotiate a little better price, say 1800 max.
Good luck on the loop.

[GEOO]

Weights are correct. 15 and 20 hp 4 strokes are light, (its a 15 hp tuned up) when you jump to 25hp, 4 strokes are heavier.

[diver dave]

Originally Posted by rjwilliams11741

I was having a hard time with the fact that you show Yamaha as being heavier than the Tohatsu and looked it up - the specs show the Tohatsu at 115 lbs for the short shaft and the 25 Yamaha short shaft at 60 lbs. If weight is an issue you might want to check those specs out again.

no way a yammi 25 is 60 lbs. The best in class Mer 15 2 st is 74 lbs.

[Hamrow]

Looks like you'll get opinions both ways so I'll throw one in. I'd definitely go 4-stroke because i'd never want the extra noise, smoke (even if it is just at startup), and oil mix hassle of a 2-stroke.
i have a 4-stroke 15hp on about the same size RIB and as others have said, 20hp is likely more than you need. Our 15 hp goes almost uncomfortably fast as is.... If i had to buy another motor I'd probably drop down to the 10 hp range or start thinking about a Torqueedo....

[Reel Grace]

Well I went with the 2 stroke 25HP Yamaha for $1850. My reasoning....... I can fix it if it breaks. usually just a dirty carb or needs spark plugs. The 4 stroke is more complicated design the may require special knowledge and computers to repair and diagnose. I Like simple. Also considering cost of ownership after a few years the Yamaha will depreciate much less and perhaps go up in value where as the new Tohatsu will most probably go down on value.