The Little Prince (1984 JS440)

Location
ATL
She's a runner!

Buttoned up ready for a test day!

Got the impeller shimmed properly.... It was way off. Cleaned up some of the electronics hopefully with the way cleaner looking flywheel & stator, also suspected the CDI/COIL so swapped them out. Praying my battery drain & weird plug nuking issues will be resolved.



1000002726.jpg

1000002723.jpg
1000002722.jpg
 
Location
ATL
So rode this
Maiden voyage with the 650 in it.
Did awesome, felt good with the 16.5 skat & 550 pump.

PXL_20250319_202242450.MP.jpg

Got it home, plugs a bit dark. I had an issue with this motor set in my other 440 murdering plugs despite running great... this honestly runs better I didn't notice any running issues tune wise.. only thing it did weird was kinda bog down when I let it idle on the trailer for 20-30 seconds. You couldn't dream of convincing me it's an electronic issue I replaced literally everything.

Currently on the SBN44
140
120
2.0 N/S
95g

So I'm just lean out the screws and see what I get next outing.
Shot in the dark but kinda speculating maybe the Seadoo box isn't the best at evacuating water it definitely kinda loaded up at idle so tossed in a JW valve.

PXL_20250319_213528016.jpg

Wax racing front fill came in! It sat far enough forward to hit my waterbox, so I trimmed the front tank fitting down a bit, heated it up and reshaped the hose bead with a 2x4.


PXL_20250320_030147216.jpg
 
Location
ATL
Rode this Saturday. Absolutely impeccable. It is just way to fun to do tailstands, got it up to 44 mph.. it's got more in it pussied out, maybe the ocean pro ride plate but it is just dying to death roll at speed lol. I can do a tailstand on this thing likely long enough to fry my lungs. Such a good ski.

Don't think I ever tried leaning it out, was super short on time. I'm hoping it's just too fat on the top end, it's not really excessive in any manor regarding load. Skat 16.5. Plugs were piiiitch black, but response is genuinely a 10/10 it is smooth 100% of the time. Idle, transition, midrange, it all feels absolutely fantastic.
 

Myself

manic mechanic
Location
Twin Lakes AR
I have also noticed mid 40's is where these things start to "roll". I've learned on mine to keep putting weight on the left as I increase speed. Just don't forget to balance out before letting off the throttle, otherwise the ski 'unwinds' and piches you off the left side!........still puts big smiles on my face though. Does the rear of yours also skate around like you're riding on marbles??
 
Location
ATL
I have also noticed mid 40's is where these things start to "roll". I've learned on mine to keep putting weight on the left as I increase speed. Just don't forget to balance out before letting off the throttle, otherwise the ski 'unwinds' and piches you off the left side!........still puts big smiles on my face though. Does the rear of yours also skate around like you're riding on marbles??

It's certainly one of those things once you lose the confidence in it and start thinking about the roll you're better off backing out. Have to put your blinders on for sure.

Marbles is a great way to describe it, basically any steering input is worthless in a handling kinda way I find on a 440/550. They only seem to properly turn when you dump them on their side. I definitely find myself primarily just kinda pointing and shooting wherever I go with them A>B

So much fun to just be rowdy on, slides, tail stands, spins, anything of the sort
 

Myself

manic mechanic
Location
Twin Lakes AR
When I have mine wide open (upper 40's) you constantly have to 'adjust' body positioning to stay on the throttle. You can literally watch the nose hunt back and forth while you're still going straight. I'd love for somebody to get some good footage and just see exactly HOW MUCH of the hull is actually still in the water LOL!!
 
16.5 seems pretty low on that. I am running a bone stock Yamaha 650 in my 1991 440 hull with a 550 pump and a straight pitch Skat 19 is perfect.
 
Location
ATL
16.5 seems pretty low on that. I am running a bone stock Yamaha 650 in my 1991 440 hull with a 550 pump and a straight pitch Skat 19 is perfect.
it definitely is I have my eyes out for something 17+ Not the easiest thing to come by at a appetizing price
 
Top Bottom