1990 JS440SX

[mrfist9]

Understood. The regular length extensions, I believe, do not do anything to change the ride of the ski. They merely replace the existing end caps which generally have water captured in them.

At some point I will drill a hole in my 550sx end caps to see if water comes out.

Then I will decide if I want to go with the regular length extensions or the XL. Choosing between the two is really like riding a regular vs an extended length ride plate -- lighter riders can use regular length while heavier riders can more easily keep the nose down with extended length.

Thank you for rescuing these vintage skis. The more there are around, the more people will be interested in two stroke stand ups. Which will be the revival of this sport.

ah see I didn't know they fill with junk but that makes sense
crap design for sure
Oddly I have zero porposing issues with the ski though at any speed any time
which odd cause the SN beats the hell out of me anything between 20 & 40+

This 440 just wants to murder me at speed

 

[E350]

Like @kevbo says, the SN SJ has a little bow to stern rocker to promote playful turny-ness which causes that wiggle at speed on straight runs but once you go faster it decreases. And you get used to it. My wife beats me on straight WOT runs on her SN SJ when I am on my FX-1.

The 440/550 hull is more flat bow to stern and is narrow, so on straight runs it can be easier to ride.

All sports have gone from long and narrow race oriented platforms to shorter, wider and some with rocker to provide more turny playfulness over the past 30 years including but not limited to whitewater kayaks, snow skis, water skis and stand up jet skis.

The 440/550 hull is/was a good design for what it was designed for.

Here is a photo to inspire you during your restoration on your 440. (My wife back in the day riding her 440 super stock which was actually her original single cylinder 1980's JS300 which Eric Burton, now in Lake Havasu City, upgraded. She is timid in saying that she went to the World's Finals, but is not ashamed to say that she got her butt kicked by the other women pro riders who were full-timers):

 

[mrfist9]

Some more work on this thing.

Got the pesky sticker under the pole



Also got out this forsaken driveshaft, center bearing, and impeller. I made a mess of myself right before leaving for a buddies for the evening. Whoops.



Gonna try and clean it inside and out in the morning

 

[mrfist9]

Finally cleaned this nasty thing out

Disgusting

 

[mrfist9]

Jettrim mat Finally showed up!

First one of these for me.
Got the bottom on and ran out of glue. Gonna grab some tonight.

 

[Myself]

Hilarious!!.........I've been putting jettrim on the 550/750 conversion ski this afternoon as well!

 

[mrfist9]

Wish the blue was a little darker but came out great!!

 

[Myself]

Heck ya!!!

 

[Sxirider44]

Came out so rad ! Love it

 

[WFO Speedracer]

I always loved the pink lightening graphics probably the best graphics they ever had.

 

[mrfist9]

I got the matching sunglasses to go with the lightning

I just NEED a pump kit now. And an x2 shaft. Have everything else

I keep stealing my friends 550SX when he falls off. Such fun hulls

 

[E350]

The Christ walked on water. So, I am pretty sure that he has been, is or will be a stand up jet skier.

In fact, I am pretty sure that He won't be mad if I add this to His Beatitudes:

"Blessed are those that restore vintage stand up jet skis,
For they promote the Joy of future riders."

 

[WFO Speedracer]

I got the matching sunglasses to go with the lightning

I just NEED a pump kit now. And an x2 shaft. Have everything else

I keep stealing my friends 550SX when he falls off. Such fun hulls

I have an excellent condition X2 driveshaft here when you get ready.

 

[mrfist9]

I have an excellent condition X2 driveshaft here when you get ready.

F*ck!!! I just panic ordered a new one from Retro

Oh well

Blackmarkit kit on the way!!!

 

[mrfist9]

Parts finally showing up.
Been playing with a new to me pitbike so this has been sitting while parts accumulate. But now I optimistically want to get it to SFF. We'll see if the last bits make it. I also acquired a 750 + electrics, I'll prolly get it going with the 650 first though to test the pump setup.

I need to find probably a better pump. And definitely a Nozzle set. Only have a X2 trim nozzle on hand.

If you got a nozzle SOS plz help

Sanded up the hull to fit the blackmarkit kit. Really nice. Some instructions would have been cool but the videos solid. I had to bend TF out of the big through hull boi to make it clear and sand the steering boi a bit to make it sit flush with the hull. Still at the test fitting stage. I'm not really stoked how the pump when snugged up against the shoe doesn't sit level with the mounting bracket. But seems to be what it is. Not sure if I'm doing something wrong or I just need to toss some shims in and move on. Also not sure if I'm supposed to run the rubber seal or not.

Another issue is I followed the template and drilled like an angel. And the right pump/bracket holes are like 1/8 off. So guess I just make the holes bigger and send it.

Research and work to do. Couldn't find my analog hole punch my springy one is too short to do the shoe. So parked for tonight.

 

[Myself]

The one I just did.......https://www.x-h2o.com/threads/550sx-to-750-all-or-nothing-build.208950/..........was about the same. I ended up with a thin shim at each rear pump mount. That, in turn, put the driveshaft almost center of the bearing holder opening.

 

[WFO Speedracer]

I probably have a 650SX or 750 ss nozzle laying around here somewhere , which particular nozzle are you looking for ?.

 

[Myself]

The 750 nozzle will only work in a 440/550 hull if you cut the arm down. That's what I did and it works great.

 

[mrfist9]

Gonna stop by a buddies this weekend and pick a pump and some nozzles. The impeller I got is a 13/18 Skat Swirl. So prolly super tall for the 650 so planning on grabbing the widest nozzles I can.

Anywho got the shoe all glued in
Also decided to glue down the last bit of the mat. Was trying to riddle how to clamp it down and this 2x4 wedged in perfect. Kinda neat

 

[WFO Speedracer]

Some info I had saved that may be of help : 92-94 standups are 80mm 95-09 are 76mm , Sts 750 had an 82mm