2004 sportster - how to increase speed??

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Hi everyone, I'm new here but have owned jetskis for a few years.

I just bought a 2004 Seadoo sportster boat and took it for a spin... brrrrr (40 degrees in NY today, haha)... just to see how it runs.

It only got up to about 35 mph and I'm wondering what I can do to make it faster. The guy that sold it to me claims that the motor was recently rebuilt...

The other thing I was wondering about is: even though I closed the drain holes, I still got water into the engine compartment, is that normal??

Any ideas would be greatly appreciated! Thanks!!!
how much water? Inspect the carbon ring assy..(under the grey shiel) for cracks/chips. As for top speed, what rpms were you getting? Possible, your compression is low, or your RAVES are carboned up, and/or your W.R.(water regulator, located on the waterbox/muffler) is defective.
2004... is it a 4tech boat? They did 2 styles that year. A 4tech, and a DI.

Either way... that boat should be running much faster. the 155hp should be getting close to 50.
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First check your rpms and then take a gps out with you to get a more accurate speed reading. That way you will know how far you are really off performance wise, if at all. As stated earlier either engine should be close to 50 mph.
LE model....

Your avatar states your boat is the LE model, which you also state is 130 hp. So, it would be the 951 DI model engine.

You've got some great replies to your speed issue so I'll address the water. This engine has a bit more to the cooling system than the other two strokes. You have a cooler under the engine at the front of the motor for the magneto. It's part #10. You need to look over all your connections to see if you have a hose loose, or split open. Depending on how much water you had in the hull, it could just be your through hull seal as Seadooya has pointed out. But, I would def look over your entire cooling circuit............:cheers:
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