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Buck 120

Yamaha 15 hp 2 stroke vs a Yamaha 20 hp 4 stroke

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Buck 120

I have a 14 foot Princecraft Fisherman with a Yamaha 15 hp 2 stroke. Last weekend the boat was sluggish with 4 people in the boat. I was considering putting a Yamaha 20 hp 4 stroke on it but with the additional weight of the motor I am wondering whether it is worth the price? Will the 20 hp be significantly faster?

The boats maximum hp rating is 20.

I don't want to spend the additional cash if the difference is negligible. If it is significant, I will consider it.

Any suggestions or comments are appreciated.

Thanks.


Not just a 3 month season but a 12 month obsession!!!

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Squaretail

You won't get much more from the 20 4 stroke. That yamaha 4 stroke lacks the low end power the 2 stroke has. I recommend going to a smaller pitch prop in the 2 stroke. This will give you more rpm and thus better use of the hp and the outboard. Will make you go a little slower when the load in the boat is minimal but when there is four people it will give more push for sure and is better on the motor. If going with new motor most likely have to go to a 20 stroke. Call the dealer for pricing just make sure you know what prop you have now ex. 9.5 x 9 pitch. Will say on side of prop hub or leading side of prop blade.

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Buck 120

Thanks Squaretail. Which pitch would you recommend going to?



Not just a 3 month season but a 12 month obsession!!!

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NorthwestHunter

If you want more low end torque swap out to a 4-blade prop. I run a 14.5" G3 with a 15 HP Honda 4 stroke with a 4 blade prop. I can squeeze out 24.9 MPH (with GPS) with 2 big guys and about 21-22 MPH with 3-4 people in the boat. The G3's also cut the water nice - which helps. The only downside is that I cannot troll slow enough for walleye etc. For that I just use my transom mount electric.


Whitetail hunting, not just a 3 month season...a 12 month obsession

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Buck 120

Looks like I have a 10 pitch prop, I ended up picking up a 9.



Not just a 3 month season but a 12 month obsession!!!

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Squaretail

That 9 should help. Or nice to try a 8. Best way is to have portable tach on the engine while testing the prop with normal load on the boat. Match wot rpm to spec.

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