Yamaha 50HP 4 stroke vs 2 stroke

[Daniel0]

Hello, there are big differences between the Yamaha 50HP 4-stroke vs the Yamaha 50HP 2-stroke, I mean consumption, noise, reliability, I saw that now Yamaha is also manufactured in new 2-strokes, I'm most interested in the power between them, is there a big difference in power?, thanks

 

[Rappey]

Translated from above -
Hello, there are big differences between the Yamaha 50HP 4-stroke vs the Yamaha 50HP 2-stroke, I mean consumption, noise, reliability, I saw that now Yamaha is also manufactured in new 2-strokes, I'm most interested in the power between them, is there a big difference in power?, thanks!

A carb type 2 stroke is lighter than a 4 stroke but uses a lot more fuel and is more noise. Reliable as long as the fuel is good.
If the 2 stroke is injected then it's lighter, more powerful and pretty close on economy.

You will get more replies posting in english ?

 

[Fire99]

You will get more replies posting in english ?

Was the Original Post in a different language. ?

 

[Fire99]

Hello, there are big differences between the Yamaha 50HP 4-stroke vs the Yamaha 50HP 2-stroke, I mean consumption, noise, reliability, I saw that now Yamaha is also manufactured in new 2-strokes, I'm most interested in the power between them, is there a big difference in power?, thanks

If you're comparing new models the 4-stroke comes in at around 20kg heavier than the 20-stroke. Around 115kg plays 95kg if comparing electric trim / tilt. So around 20% heavier with the 4T. Now I'm not sure if this is fully 'wet' including oil, as the 4T will have engine oil where the 2T won't..
Hard to say on fuel economy but I've found 4T's are more frugal on fuel mostly on part - mid throttle but with the margins narrowing at Wide Open Throttle. I generally still prefer 2-stroke for outboards as for me they are more forgiving with maintenance, but the most recent 2-strokes do seem quite technical to get emissions under control.. (Just personal experience and chatting to an engineer I've known - I'm not a pro.)

 

[Hot Property]

50 HP is 50 HP regardless of 2 or 4 stroke.

The 2 stroke will have better torque so quicker pickup, but the 4 stroke will be smoother, quieter and significantly more economical.

You cannot buy a new 2 stroke in the UK unless you are a commercial user....

 

[Fire99]

You cannot buy a new 2 stroke in the UK unless you are a commercial user....

True in practice rather than technology. Just that emissions regs killed 2-stroke tech in smaller outboards (since smaller ones are all carb fed as far as I know). It wasn't that long ago you could still by an Evinrude E-Tec 2-stroke in larger engines in the UK. (I knew a dealer that sold them). Unfortunately Bombadier killed off Evinrude and that was that.

 

[Rappey]

Was the Original Post in a different language. ?

Yes. It was romanian.

You cannot buy a new 2 stroke in the UK unless you are a commercial user....

If its injected then you can buy. There are many 300cc 2t injected moto-x bikes on the market nowadays. Not so much available with outboards though.
I had a mariner 90 2t, changed it to evenrude e-tec 90 . It was like i had upgraded to a 120. Lots more acceleration and top speed went from 26 to 32 knts !
The injected 2t can be as economical as a 4t, better emissions as it fires on every stroke rather than every other like a 4t and lots lighter.
I would personally opt for a injected 4t over a carb 2t any day as never had fuel issues with injection but carbs always seem to need stripping on a 2t with modern fuel

 

[LiftyK]

Having owned both two-stroke and four-stroke Yamaha engines in the 50-100 HP range, my advice would be:

Noise - the quiet nature of the four-stroke makes a huge difference to the onboard experience.

Torque - the dealer insisted he fit hydraulic steering on the four stroke to prevent the wheel flying out of my hand if the throttles were opened when the engine was slightly turned. I don't think you will be sort of torque.

The downsides of the four-stroke are weight, price and, I believe, higher service costs. Despite these factors I'd always get a four-stoke vs. a two-stroke, new or second hand.