Yamaha 252 Fuel Economy

[Mac’nCheese]

I just happened to read the boat test reviews for the Yamaha 252SD and the Scarab 255, and the quoted difference in fuel economy is just astounding. Is Scarab really getting nearly double the fuel economy as Yamaha?

Yamaha:

Yamaha 252SD (2021-) | BoatTEST

boattest.com

Scarab:

Scarab 255 ID (2019-) | BoatTEST

boattest.com

 

[tkeru408]

Can't comment on the Scarab, but I can say the one time I paid attention to my GPH it was ~11.5 GPH running at about 5700 rpm and 27 mph which is right in line with their chart between the 5500 and 6000 rpm lines.

On a separate note, unlike their chart, my top speed is higher than 43.8 mph. I believe pretty much everyone else also reports tops speeds in the high 40s.

 

[Mac’nCheese]

I guess I'm just a bit flummoxed at the 4.8 mpg claim on the Scarab. If true, that's insanely good economy for a 25 foot boat running twin 250's. Shoot, even my previous AR195 only got 2.0-2.5 mpg.

It almost feels like the Scarab is reporting out fuel consumption on each engine, and someone didn't catch that in the reporting. Sorry, having a hard time wrapping my head around a 500hp, 25 foot boat getting nearly 5mpg at cruise speed.

 

[tkeru408]

Agreed--seems off.

 

[1969mach1]

My last boat was a 1998 30" Bayliner Express Cruiser with a single screw 454. We also measured fuel economy in MPG, but it was "meters" per gallon. Having been out of boating for two decades, I a pleasantly surprised and how efficient my recently ordered 252SE is going to be.

 

[foozed]

Can't comment on the Scarab, but I can say the one time I paid attention to my GPH it was ~11.5 GPH running at about 5700 rpm and 27 mph which is right in line with their chart between the 5500 and 6000 rpm lines.

On a separate note, unlike their chart, my top speed is higher than 43.8 mph. I believe pretty much everyone else also reports tops speeds in the high 40s.

We don't get anything past 43 with just me on board. When I have a few passengers we can only hit 42.
Calm lake conditions in NC, not a high elevation or anything.

 

[HangOutdoors]

I have been reviewing some of the Scarabs, and noticed this as well. Also their Gas Tanks are much smaller 41 gallons and 56 gallons , vs 50 gallons, 70 gallons and 110 gallons on the Yamaha's respectively. It seemed that their range and gph were significantly better on the Scarab unless I misread something from the Test Reports. Would like to understand it all better.

 

[tkeru408]

We don't get anything past 43 with just me on board. When I have a few passengers we can only hit 42.
Calm lake conditions in NC, not a high elevation or anything.

NC lakes here, too. I've only tested WOT a few times, all in calm conditions but with varying configs of people and gas on board, and my top speed has varied between 45 and 48.

 

[foozed]

NC lakes here, too. I've only tested WOT a few times, all in calm conditions but with varying configs of people and gas on board, and my top speed has varied between 45 and 48.

Bimini open or collapsed? I often think its a wind sail!

 

[Stan M]

Bimini open or collapsed? I often think its a wind sail!

With Bimini open and 8 people on board, with 1/2 tank fuel, I got 48mph. Also had room to go on the throttle. Have had to 52 mph with 4 on board.

 

[tkeru408]

Bimini open or collapsed? I often think its a wind sail!

Fixed frame bimini like yours and the canvas stays on.

 

[Julian]

When I look at the boattest.com written results on the 2019 255 Open ID they say the following:

According to fuel-burn test numbers provided by the manufacturer, best economic cruise speed for the Scarab 255 Open ID with the twin 300-hp Rotax engines is at 5000 rpm, where on their test the boat ran at 28.8 mph (46.35 kph) and burned 11.9 gph (45.05 lph) for a range of 122 statute miles (196.3 km). On our test, we saw a two-way average speed of 34 mph (54.72 kph) at that rpm level.​

​

That is more than double what the graph above says:
5000 rpm 11.9GPH (article above)
5000 rpm 4.5GPH (Chart above)

Something is amiss. The above is for the 300hp engines.

But if you look at the 2016 test of the 250HP engines it is double too:



No way they doubled their efficiency!

 

[1969mach1]

Yeah, this is pretty simple, if you just double the GPH for the scarab, all the numbers come out in what you'd consider reasonably normal range. All the other numbers except MPH are derivative numbers. So MPH and GPH were used to calculate where MPH is neither here not there to twin vs single equation.

Clear that the fuel usage is per engine and someone forgot to double it for the twins. Maybe someone in marketing who didn't know it had twins.

 

[CycoRyder]

buying a boat and worrying about fuel consumption = buying a corvette and worrying consumption = should not have purchased a boat or corvette.. seriously?? fuel consumption.. damn..

 

[Adrian @ JB Solutions]

buying a boat and worrying about fuel consumption = buying a corvette and worrying consumption = should not have purchased a boat or corvette.. seriously?? fuel consumption.. damn..

I would generally agree, though the topic of this thread is the ridiculous number Scarab has listed.

 

[CycoRyder]

Agreed..

 

[1969mach1]

buying a boat and worrying about fuel consumption = buying a corvette and worrying consumption = should not have purchased a boat or corvette.. seriously?? fuel consumption.. damn..

People say it's a lot easier to get rich than to stay rich. I grew up extremely poor. Like welfare poor. Not worried about posting that on this forum as all my friends and many of my clients know this. I'm not embarrassed as it wasn't my fault I had crap for parents. That said, god has shined on my life and I can afford to buy boats much more expense than the 252SE I have on order. But, my childhood circumstances of being poor still stick with me and I do look at operating cost, and fuel consumption was actually part of my decision making process.

I think a lot of people with money got it and keep it by being frugal.

 

[CycoRyder]

BS.. no one buys a jet boat to run a business / charter rides etc.. it is considered a luxury item.. therefore non-essential.. if you're concerned about fuel economy and running costs and you ordered 252se.. the joke is on you.. "pitty me I grew up poor" so what dude.. get over yourself.. a 252se?? really?? be done with me PLEASE!!

 

[Adrian @ JB Solutions]

BS.. no one buys a jet boat to run a business / charter rides etc.. it is considered a luxury item.. therefore non-essential.. if you're concerned about fuel economy and running costs and you ordered 252se.. the joke is on you.. "pitty me I grew up poor" so what dude.. get over yourself.. a 252se?? really?? be done with me PLEASE!!

Plenty of people running Yamaha jet boats on charters

 

[212s]

I just happened to read the boat test reviews for the Yamaha 252SD and the Scarab 255, and the quoted difference in fuel economy is just astounding. Is Scarab really getting nearly double the fuel economy as Yamaha?

The Boattest data is for one engine only, and it's the wrong engine type 200hp vs 250hp in the test report. Scarab's own literature says the 250hp pulls 4gph at 5k and ramp up to 18gph WOT per engine = 36gph WOT.

Cruising around they're similar. WOT and in the high rpm ranges, the BRP engines consume more fuel for similarly rated engines and performance levels due to the superchargers cramming more fuel into the 3 cyl engines.

I blame this on poor editing of the info on the Boattest reviews. I've seen this happen several times where the results don't match the review.

I don't watch fuel consumption too much as we have the boat for fun, not to watch the fuel gauge.