New Technology Outboard 2 CR props one shaft

[EZM]

Saw this innovation and it looks interesting ....

Suzuki (which is a major player on small to mid sized outboards everywhere in the world except north america) introduced a new engine 350 hp with 2 counter rotating props on one shaft.

According to independent testers and Suzuki itself (always take the manufacturer's pitches with some skepticism) the advantages are faster hole shot, more torque, far less bow lift and better control and tracking.

Looks interesting.

I will wait for a few years of "real world testing" to see how this pans out in the long run with maintenance, longevity, or any host of "brand new issues" associated with "brand new technology".

Now keep in mind - double props has been around - but counter rotating props on the same shaft is new.

Thoughts?

https://www.youtube.com/watch?v=uGK9EiqDZw4&feature=emb_rel_end

https://www.boats.com/reviews/suzuki-df350a-twin-propeller-outboard-engine-introduced/

[Moosetalker]

Sounds complicated as in more moving parts and need an engineering/tech degree to fix in the field.

[Osky]

Interesting M....
I wonder how low in horsepower they will go? For me, the bonuses you mention wouldnt mean much under 40 hp. I wonder as well what parts suffer if a guy finds a gravel bar or unknown deadhead etc?

Osky

[Walleyedude]

I don't think this is a new innovation, it's been around in sterndrive applications for a long time. Volvo has been using counter-rotating propellers on the same shaft since the early 1980s, and Mercury has had the Bravo 3 since at least the late 80s. It's proven technology at this point.

My brother has a Bravo 3 stern drive on his boat. I can attest to how good the handling is, especially at lower speeds, and the holeshot is incredible for a boat its size. The down side is a lack of top speed, and of course, the cost and complexity of any repairs and the lack of options when it comes to props due to cost and availability.

I know of a few guys running the Suzuki 350 on 20' Warriors, and they all love them. Great handling, good gas mileage, and completely reliable. The downside is they're heavy, and they're 5+ mph slower than boats with a Mercury Verado 350.

[Drewski Canuck]

WELLLLL the whole idea of counter rotating props was pioneered by the Germans in WW1 & 2 in the early torpedoes that used the same system, and sank ships very well, because they tracked so straight.

Single props tend to 'twist" to one side.


But yes, Volvo has been doing this for years, and there are a number of wakeboard boats that have the props FACING FORWARD, and counter rotating as well.

Scary part is any damage and it is very expensive to fix due to two separate shafts turning propellers, one on the inside shaft, and one on the outside shaft.

Still beats using trim tabs to overcome the lean from the prop torque, or the stingray stabilizer on the lower leg.

Drewski

[EZM]

WELLLLL the whole idea of counter rotating props was pioneered by the Germans in WW1 & 2 in the early torpedoes that used the same system, and sank ships very well, because they tracked so straight.

Single props tend to 'twist" to one side.


But yes, Volvo has been doing this for years, and there are a number of wakeboard boats that have the props FACING FORWARD, and counter rotating as well.

Scary part is any damage and it is very expensive to fix due to two separate shafts turning propellers, one on the inside shaft, and one on the outside shaft.

Still beats using trim tabs to overcome the lean from the prop torque, or the stingray stabilizer on the lower leg.

Drewski

of course .......... the Germans !!!!!! :)

[EZM]

I don't think this is a new innovation, it's been around in sterndrive applications for a long time. Volvo has been using counter-rotating propellers on the same shaft since the early 1980s, and Mercury has had the Bravo 3 since at least the late 80s. It's proven technology at this point.

My brother has a Bravo 3 stern drive on his boat. I can attest to how good the handling is, especially at lower speeds, and the holeshot is incredible for a boat its size. The down side is a lack of top speed, and of course, the cost and complexity of any repairs and the lack of options when it comes to props due to cost and availability.

I know of a few guys running the Suzuki 350 on 20' Warriors, and they all love them. Great handling, good gas mileage, and completely reliable. The downside is they're heavy, and they're 5+ mph slower than boats with a Mercury Verado 350.

It can't be cheap either. I doubt it will show up on smaller outboards - but a rig like yours (a heavy glass boat) I could see it.

For some, top speed seems to be the "measurement" of an outboard for sure - and if you make your money fishing then getting to the next spot as fast as you can so you can fish longer definitely is a big factor.

For recreational Joes like me, having less bow lift, more control and torgue are more important. Although I have a 9.9 kicker, my main engine still has a low pitch prop to achieve better control and hole shot - which to me are way better things to have.

Sure, I dropped 7-8 mph in top speed by going all the way down in pitch, but my boat, even with the prop it wears will go 45 mph (72 km/hr) with all my gear a tank of gas and a few of us in the boat. That's all I need. And, quite frankly, I rarely cruise over 35 mph.

For me getting to 53 mph (85 km/hr) and trading it off for way less control around the dock and not being able to troll the engine down below 2.5 mph when it's too choppy or windy for the 9.9 isn't a trade off for me.

Maybe this technology comes down to mid sized outboards in the 150-200 hp range in the future. I might try it (as long as it was an engine make I'd want).

But yeah, it's interesting. I didn't realize the Volvo was a true counter rotating prop with a separate gear and spline like this one - I always thought of it as some sort of "hydro static" type thing with a "clutch and gear" thing ..... pretty cool still.