Yamaha AR192 Low Top Speed

[Bmann87]

I just bought a 2013 yamaha ar192. First day out totally empty boat half tank of fuel, would not go past 40mph. After adding a couple kids and a tube best I saw was 35mph (WOT)

1) The gas is likely old from last season (not positive, but I believe 87 octane)
2) I noticed it only revs to 6800 rpm (seen others in the forum indicating 7400 rpm)
3) shouldn't be heat soak as these tops speeds were tested after 10 minutes of no wake speed
4)

Any ideas on what could cause such a low top speed at WOT? Low engine hours been maintained well and sounds completely normal.

 

[Bmann87]

500 ft above sea level. Not sure when the plugs were changed last

 

[I_squared_r]

Check that your air filter isn't clogged with oil. This happened to me from previous owner fogging incorrectly. I would start there then go put fresh plugs in.

 

[Cobra Jet Steering LLC]

Add octane booster to your fuel also

 

[RNYCLV]

That engine is meant for 93 or higher
You wont see a top speed much higher than that on that boat though...maybe 5 -7 more

 

[Bmann87]

That engine is meant for 93 or higher
You wont see a top speed much higher than that on that boat though...maybe 5 -7 more

5-7 mph would be incredible imo. 35 mph just doesnt seem right. People are claiming 7700, Im not where near that. I will def check the fuel

 

[swatski]

Do 2013 192s have knock sensors? I didn't think so. I bet this boat will be faster on 87 than 93.

--

 

[swatski]

May also want to check the supercharger (clutch) - if it spins in both directions that may indicate it is shot and would explain your situation.

 

[Bmann87]

May also want to check the supercharger (clutch) - if it spins in both directions that may indicate it is shot and would explain your situation.

Interesting, I need to look into this. Hopefully there is some articles on here around this.

 

[Crob83]

That engine is meant for 93 or higher
You wont see a top speed much higher than that on that boat though...maybe 5 -7 more

Actually 91 or higher is what is recommended

 

[swatski]

This is from @SamCF - the legendary sx192 owner with crazy mods and >60mph consistent max speeds.

Before all his extensive mods he posted several tests of best speeds and consistently claimed 87 was the fastest gas. This was several years ago, but can be found in his threads.

Here is a direct quote:

SHO runs best on 87 octane 10% ethanol. SVHO requires 91 or higher. The supercharged engines do run a knock sensor.

EDIT: I stand corrected on knock sensors in 192s, I guess.

 

[I_squared_r]

I've been running 87 in my SHO for the last 150 hours and runs up to 50mph. I dislike the move to a higher compression ratio on the later SVHO engines.
I second checking the supercharger clutch. I would do Check air filter > check clutch > change plugs. Its a good chance that would resolve your problem.

 

[RNYCLV]

our manual states Recommend fuel: Minimum Octane Rating of 90 (Pump octane number) = (R + M)/2
90 (Research octane number)
Speed at 87 may be true, I dont use 87...
We had our supercharged engine tuned and have used 93 or higher ever since as suggested.

 

[RNYCLV]

Actually 91 or higher is what is recommended

Before we had the engine done was 90 or higher, since then its stated supercharged are suggested 93 or higher. Thats just what the manual says...I'm sure if we were to mess with different things we would see different results. But always nervous to go against what they suggested. Always open to discussion though.

 

[I_squared_r]

our manual states Recommend fuel: Minimum Octane Rating of 90 (Pump octane number) = (R + M)/2
90 (Research octane number)
Speed at 87 may be true, I dont use 87...
We had our supercharged engine tuned and have used 93 or higher ever since as suggested.

Your boat is a 2018 so you have the SVHO engine so 87 octane isn't recommend. I think it was 2016 that yamaha changed the SHO to SVHO. The difference being the timing chain and compression ratio. I'm not sure what else.

 

[RNYCLV]

Your boat is a 2018 so you have the SVHO engine so 87 octane isn't recommend. I think it was 2016 that yamaha changed the SHO to SVHO. The difference being the timing chain and compression ratio. I'm not sure what else.

Understood, .... makes sense, thank you

 

[FSH 210 Sport]

Your boat is a 2018 so you have the SVHO engine so 87 octane isn't recommend. I think it was 2016 that yamaha changed the SHO to SVHO. The difference being the timing chain and compression ratio. I'm not sure what else.

Isn‘t the SHO normally aspirated and the SVHO a supercharged engine?

 

[I_squared_r]

Isn‘t the SHO normally aspirated and the SVHO a supercharged engine?

The HO is normally aspirated. SHO is supercharged. SVHO is the latest supercharged motor.

I found this on a website talking about yamaha's switch to the new SVHO in the FX cruiser https://www.boatingmag.com/boats/yamaha-fx-cruiser-svho/

"...The addition of the V to the suffix is because Yamaha revamped the existing 1.8-liter, SHO engine. A new, larger six-vane supercharger produces 60 percent more boost. The intercooler, used to cool the air that supercharger takes in, also gets upsized and, according to Yamaha, increases efficiency by 22 percent. Additional upgrades include stronger, forged pistons, a vastly more efficient oil cooler and larger fuel injectors. With the increased power, Yamaha also addressed the jet pump. It is upsized to 160 mm, features a larger exit diameter..."

I'm not sure if the AR195 got the larger pump

EDIT: I just learned something new while googling. It looks like Yamaha had to change the SVHO exhaust cams to a shorter duration for emissions thus causing the motor to run a little hotter. Which could explain why the designers put forged pistons, higher compression ratio, and upgraded intercooler to maintain/bump horsepower numbers. Some of the jet ski guys are putting the older SHO exhaust cams in their SVHO for a power boost. I just thought this was interesting and probably explains why some people have got great performance on the SHO by modding timing curves and upgrading the intercooler.

 

[FSH 210 Sport]

I just bought a 2013 yamaha ar192. First day out totally empty boat half tank of fuel, would not go past 40mph. After adding a couple kids and a tube best I saw was 35mph (WOT)

1) The gas is likely old from last season (not positive, but I believe 87 octane)
2) I noticed it only revs to 6800 rpm (seen others in the forum indicating 7400 rpm)
3) shouldn't be heat soak as these tops speeds were tested after 10 minutes of no wake speed
4)

Any ideas on what could cause such a low top speed at WOT? Low engine hours been maintained well and sounds completely normal.

The HO is normally aspirated. SHO is supercharged. SVHO is the latest supercharged motor.

I found this on a website talking about yamaha's switch to the new SVHO in the FX cruiser https://www.boatingmag.com/boats/yamaha-fx-cruiser-svho/

"...The addition of the V to the suffix is because Yamaha revamped the existing 1.8-liter, SHO engine. A new, larger six-vane supercharger produces 60 percent more boost. The intercooler, used to cool the air that supercharger takes in, also gets upsized and, according to Yamaha, increases efficiency by 22 percent. Additional upgrades include stronger, forged pistons, a vastly more efficient oil cooler and larger fuel injectors. With the increased power, Yamaha also addressed the jet pump. It is upsized to 160 mm, features a larger exit diameter..."

I'm not sure if the AR195 got the larger pump

EDIT: I just learned something new while googling. It looks like Yamaha had to change the SVHO exhaust cams to a shorter duration for emissions thus causing the motor to run a little hotter. Which could explain why the designers put forged pistons, higher compression ratio, and upgraded intercooler to maintain/bump horsepower numbers. Some of the jet ski guys are putting the older SHO exhaust cams in their SVHO for a power boost. I just thought this was interesting and probably explains why some people have got great performance on the SHO by modding timing curves and upgrading the intercooler.
[/QUOTE]

Respectfully submitted…

The 2013 AR 190 has the 1.8L HO normally aspirated engines which makes sense when reading the manual which states the minimum octane required is 86. All of the super charged engines require 91 octane.

https://specs.boatguideweb.com/specifications/yamaha/sport_boat/ar190/2014/

If you can find non ethanol fuel run that instead of the ethanol laced fuel. I have 85 and 91 non ethanol fuel and mix them in the correct proportions to get 86. Running higher than specified octane fuel decreases performance and increases the rate at which the money leaves your wallet. If you cannot find non ethanol fuel, be sure and run Star Tron marine fuel additive or it’s equivalent to prevent phase separation that can occur when using ethanol laced fuel. It probably wouldn’t hurt to run a dose of Techron fuel system cleaner through the tank as well since the boat is a few years old.

In addition to the other good suggestions, check to make sure the engine oil has not been over filled. This is what leads to the air filter becoming oil fouled in some cases. There are also some posts about decreased engine rpm’s with too much oil.

Lots of posts on this site about regaining 500 rpm’s of performance with a spark plug change.

Since the boat is new to you, just do a basic tune up of air filter, oil and filter, and spark plug change to set you up for a full summer of great memory making.

 

[Bmann87]

I've been running 87 in my SHO for the last 150 hours and runs up to 50mph. I dislike the move to a higher compression ratio on the later SVHO engines.
I second checking the supercharger clutch. I would do Check air filter > check clutch > change plugs. Its a good chance that would resolve your problem.

Does an

The HO is normally aspirated. SHO is supercharged. SVHO is the latest supercharged motor.

I found this on a website talking about yamaha's switch to the new SVHO in the FX cruiser https://www.boatingmag.com/boats/yamaha-fx-cruiser-svho/

"...The addition of the V to the suffix is because Yamaha revamped the existing 1.8-liter, SHO engine. A new, larger six-vane supercharger produces 60 percent more boost. The intercooler, used to cool the air that supercharger takes in, also gets upsized and, according to Yamaha, increases efficiency by 22 percent. Additional upgrades include stronger, forged pistons, a vastly more efficient oil cooler and larger fuel injectors. With the increased power, Yamaha also addressed the jet pump. It is upsized to 160 mm, features a larger exit diameter..."

I'm not sure if the AR195 got the larger pump

EDIT: I just learned something new while googling. It looks like Yamaha had to change the SVHO exhaust cams to a shorter duration for emissions thus causing the motor to run a little hotter. Which could explain why the designers put forged pistons, higher compression ratio, and upgraded intercooler to maintain/bump horsepower numbers. Some of the jet ski guys are putting the older SHO exhaust cams in their SVHO for a power boost. I just thought this was interesting and probably explains why some people have got great performance on the SHO by modding timing curves and upgrading the intercooler.

Respectfully submitted…

The 2013 AR 190 has the 1.8L HO normally aspirated engines which makes sense when reading the manual which states the minimum octane required is 86. All of the super charged engines require 91 octane.

https://specs.boatguideweb.com/specifications/yamaha/sport_boat/ar190/2014/

View attachment 178264

If you can find non ethanol fuel run that instead of the ethanol laced fuel. I have 85 and 91 non ethanol fuel and mix them in the correct proportions to get 86. Running higher than specified octane fuel decreases performance and increases the rate at which the money leaves your wallet. If you cannot find non ethanol fuel, be sure and run Star Tron marine fuel additive or it’s equivalent to prevent phase separation that can occur when using ethanol laced fuel. It probably wouldn’t hurt to run a dose of Techron fuel system cleaner through the tank as well since the boat is a few years old.

In addition to the other good suggestions, check to make sure the engine oil has not been over filled. This is what leads to the air filter becoming oil fouled in some cases. There are also some posts about decreased engine rpm’s with too much oil.

Lots of posts on this site about regaining 500 rpm’s of performance with a spark plug change.

Since the boat is new to you, just do a basic tune up of air filter, oil and filter, and spark plug change to set you up for a full summer of great memory making.
[/QUOTE]
Love this post BTW, thanks!