Questions for Those Knowledgeable on the 2023 Ultra 310LX

[kestrel452]

Howdy y'all. I am considering a 310LX to replace my 2022 FX Cruiser HO and have some questions if anyone is able to offer any help. Thank you in advance for any insight

First, I'd like to know how reliable and accurate the fuel gauges on these tend to be, versus the cluster-f that is the FX's fuel gauge. The Kawi manual actually says the alarm is supposed to come on at 4 gallons "usable", which would be a huge improvement over the FX's gauge reading near-empty at 10 gallons left. Have y'all noticed how close the fuel gauge actually comes close to what's actually left in the tank?

Second, the Kawi manual says it needs 90-octane fuel (not 91 or 93). However, 89-octane midgrade is almost always what I come across at fuel docks. The lead tech at my dealer said running it on 89 if need be shouldn't hurt the engine, so long as I don't try to pin it all the way. Is this true?

Third, how much more gas do these burn compared to the likes of the SVHO or 300hp SeaDoos? I'm trying to get an idea if the increase in usable fuel on the Kawi 310 (between the fuel alarm going off at a more reasonable point, and larger tank), will actually lead to being able to spend more time on the water compared to my FX Cruiser HO, even if it's just around 45 minutes. That is assuming I'm cruising below 50mph...I realize that the 310LX will sip its entire tank in under an hour when pinned. Think the 310LX even has an "economical riding indicator" to help you conserve gas...as well as a boost pressure gauge to help you stay out of the boosted RPM range.

Fourth, on the same topic of fuel economy...does anyone have any earthly idea of what is approximately the best cruising speed of these, and what their statute mile range is at best cruise?

Thanks again, fellas.

[Mr. GP1800]

Howdy y'all. I am considering a 310LX to replace my 2022 FX Cruiser HO and have some questions if anyone is able to offer any help. Thank you in advance for any insight

First, I'd like to know how reliable and accurate the fuel gauges on these tend to be, versus the cluster-f that is the FX's fuel gauge. The Kawi manual actually says the alarm is supposed to come on at 4 gallons "usable", which would be a huge improvement over the FX's gauge reading near-empty at 10 gallons left. Have y'all noticed how close the fuel gauge actually comes close to what's actually left in the tank?

Second, the Kawi manual says it needs 90-octane fuel (not 91 or 93). However, 89-octane midgrade is almost always what I come across at fuel docks. The lead tech at my dealer said running it on 89 if need be shouldn't hurt the engine, so long as I don't try to pin it all the way. Is this true?

Third, how much more gas do these burn compared to the likes of the SVHO or 300hp SeaDoos? I'm trying to get an idea if the increase in usable fuel on the Kawi 310 (between the fuel alarm going off at a more reasonable point, and larger tank), will actually lead to being able to spend more time on the water compared to my FX Cruiser HO, even if it's just around 45 minutes. That is assuming I'm cruising below 50mph...I realize that the 310LX will sip its entire tank in under an hour when pinned. Think the 310LX even has an "economical riding indicator" to help you conserve gas...as well as a boost pressure gauge to help you stay out of the boosted RPM range.

Fourth, on the same topic of fuel economy...does anyone have any earthly idea of what is approximately the best cruising speed of these, and what their statute mile range is at best cruise?

Thanks again, fellas.

I would never run a Kawi on anything less than 93 octane. They need good fuel. Of all of the stories around of here with 310s failing it almost always seems to come down to fuel quality.

[steve45]

The fuel gauges on my older LXs and 310X come on too early IMO. Somewhere around 7 gallons remaining. I don't know how much unusable fuel remains when it runs out.

I would not run less than 90 octane, and it should be pretty fresh. Storing fuel reduces it's octane. The '22s had problems with the knock sensor programming, but that's been fixed now.

I really don't know the range of the 310, as I don't take it for long cruises. I run my normally aspirated Ultra LXs at about 30 MPH on long cruises and I think the range would be about 70 miles with a few gallons reserve. I refuel at about 40 miles. Range will depend a lot upon water conditions, wind, and weight. Since it's the same hull, the power requirements, and hence fuel requirements, would be about the same.

[pro1200]

These are all valid questions but unfortunately are hard to answer. The main problem I see with a 310 Kawi is finding a fuel with an adequate octane. I used to run my '17 Sea-Doo 260 in the Gulf of Mexico and the low fuel warning came on when there was still about 5 gallons left in a 16 gallon tank. This is about 20 miles of riding. I got tired of having range anxiety so I just mounted a spare 4 gallon container on the rear.

[john belton]

Since the majority of your questions here revolve around “octane and range”, I think you’re looking at the wrong Ski. But first, I would not put 89 Octane in a 310 Ultra under any circumstances! If you run out of gas on a 310 and 89 octane is the only solution, you’re better off getting towed back to your Trailer.

Perhaps consider the STX 160. On mine I’ve gone 126 miles on a tank on 87 octane. If the water were you ride is not too rough, this is a pretty fun Ski. I hope this helps your decision. JB.

[kestrel452]

Since the majority of your questions here revolve around “octane and range”, I think you’re looking at the wrong Ski. But first, I would not put 89 Octane in a 310 Ultra under any circumstances! If you run out of gas on a 310 and 89 octane is the only solution, you’re better off getting towed back to your Trailer.

Perhaps consider the STX 160. On mine I’ve gone 126 miles on a tank on 87 octane. If the water were you ride is not too rough, this is a pretty fun Ski. I hope this helps your decision. JB.

I'm starting to think this is true. The 160LX is appealing as an idea...but I cannot help but think that hull is underpowered with only 160hp. I really wouldn't want anything slower feeling than my FX Cruiser HO.

[john belton]

I'm starting to think this is true. The 160LX is appealing as an idea...but I cannot help but think that hull is underpowered with only 160hp. I really wouldn't want anything slower feeling than my FX Cruiser HO.

I have a 2022 160STX and also a 2022 310X. I can tell you first hand the 160 is pretty quick and will reach 62ish mph on a good day / good conditions. In these conditions you can expect as good or better overall performance than the normally aspirated YAM FX HO.

I won’t lie to ya . . . I love that 310. It’s a great Ski but I don’t ride it all the time. As with most things, “choices” are comprised of “compromises”!!!

Well whichever way you go, you’re sure to have fun. JB.

[kestrel452]

I have a 2022 160STX and also a 2022 310X. I can tell you first hand the 160 is pretty quick and will reach 62ish mph on a good day / good conditions. In these conditions you can expect as good or better overall performance than the normally aspirated YAM FX HO.

I find this to be very surprising...the Ultra 160 will get out of its way as quickly as the FX HO despite being lower horsepower and heavier?? I think the STX 160 is a smaller/lighter craft than the Ultra if that's what you're basing the N/A 160 engine off of. If you could expand on that at all, I would appreciate it.

[Cranofwaterfell]

Since the majority of your questions here revolve around “octane and range”, I think you’re looking at the wrong Ski. But first, I would not put 89 Octane in a 310 Ultra under any circumstances! If you run out of gas on a 310 and 89 octane is the only solution, you’re better off getting towed back to your Trailer.

Perhaps consider the STX 160. On mine I’ve gone 126 miles on a tank on 87 octane. If the water were you ride is not too rough, this is a pretty fun Ski. I hope this helps your decision. JB.

I hope to never find myself in this situation, but if I did I'm pretty sure it will not damage the engine IF (BIG IF) you go really slow/keep rpms way down so the boost is not a factor. This would be emergency type situation just to get ski home or back on trailer. I would not let anyone else do this on my ski (to insure that the revs stay low along with the compression).

The way I see it you would in effect be running a normally aspirated (Ultra LX) which only requires 87 octane. On my ski the boost is non existent at low speeds, like zero on the gauge when your idling along going slow.

[Rescue1]

The previous 300/310 model had less floats on the fuel level sender unit, the new one has more making it more accurate. And it's mandatory that 90+ octane be put into a 310. It's a pain sometimes, but is what it is unless you want to melt a piston. Luckily the new Ultras have a more sensitive knock sensor, and if it see's any sort of knock it will put the engine into Limp mode. Engine damage is still likely even with this safeguard.