Build or Blowup? JS550

Hey all!! Just picked up this 87 JS550 (or at least I think) for a couple hundred bucks and wondering what I should do with it. Drained the old gas, fixed the weird fuel routing from previous owner, new battery, and it now runs well enough to ride. The main issue it has is the starter cranks very slow and the carb could use a tuning. Power seems ok mid range but bogs 3/4 to full throttle.

What I know:
-It’s a 550 head
-has 439cc stamped on the case so not sure what that means
-the carb is likely not the original. The small rpm limiter line that normally runs to the right side of the carb to richen the mixture went nowhere and the carb doesn’t even have the nipple…

What I think:
-start out with new carb that a lot of people recommend on these forums
-throw a new starter on
This will get it running like it should assuming it has the necessary compression and crank seals aren’t leaking air.

So anyways, I’m posting to see if anyone can give any insight on the carb and slow crank situation, but more importantly should I do the bare minimum to get it running well and have fun beating on a $200 ski for the summer or should I have fun doing a little fiberglass work, engine rebuild/complete bearing and seal overhaul, half decent paint job, and new hydro turf?

Appreciate the advice!!

clean the carb and tighten/replace the ground cable. Ride the ski then do any rebuilds/mods in the fall/winter.

Second that. Ride it all summer to see if you even want to put all that effort into it over winter

Appreciate it that’s where I’m leaning towards. I think this ski has a 440 bottom end (I’m pretty sure the same as a 550 but different sized jet) and a 550 top end. The only thing is I also believe it has a 440 carb bn38 from the looks of eBay comps. Should I at least buy a stock carb on eBay or upgrade?

Here is what I know for sure , the stock starters on those are junk , they never worked well and slow starting was normal, it will run better with a 44 carb but you will need an intake manifold anyway so go with one that will fit an SBN carb , the old BN 44 carbs are not worth the hassle .

You just pointed out the two things they had the most issues with on these skis , the 38BM carbs worked pretty well , the 44's did not.

Brutally honest opinion get rid of that thing and get something reeded at least a 550sx motor, preferably a superjet

spinyard said:

Brutally honest opinion get rid of that thing and get something reeded at least a 550sx motor, preferably a superjet

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I wouldn't go so fgar as to say get rid of it but I wouldn't put a lot nu money into it either , 550's can become serious money pits.