Help with 1996 Sea Doo SPX 720cc

[CHEAP THRILLS]

My wife and I acquired a 96 SPX 720 and 99 Yamaha GP800 last week. We took them out this past Saturday and had a blast minus a few hiccups. I ride the GP800 except when she wants to go faster. That brings up the HELP question... She hates being last, and my big ass on that little ski does't work very well!!! Any ideas on inexpensive mods to make to the ski to help her top end speed? The VTS isn't working and was in the full up position, I lowered it manually by taking the VTS motor off and turning the star wheel till I reached a neutral position. My guess is that will help slightly. The previous owner was premixing the gas @24-1 which I know is way too rich (it's like mosquito control behind her), I started mixing 40-1, but haven't gotten all the old gas run through yet. The ski has a R&D ride plate and what looks like a different exhaust pipe installed (manifold is white, pipe and stinger are purple)

Thanks for any and all help,
Pat

 

[mikidymac]

The purple pipe is stock for that ski. Honestly there really isn't much you can do to help that ski go faster as it is what it is. You could ad a Factory performance pipe to it but you will be sacrificing a lot of reliability.

The 40:1 premix is prefered but you have to be using API-TC oil, not the TCW-3 oil the yamaha takes. Seadoo has a much different oil spec. Also the Seadoo is a rotary valve engine so you have to make sure you still have the oil tank and are supplying the rotary gear inside the crankcase with oil. Some people will loop the lines and check it to make sure the flooded cavity always has a supply of oil.

 

[CHEAP THRILLS]

That's interesting about the rotary valve oil. I was told by the previous owner that no oil needed to be put in the tank and to premix only. Am I doing something wrong here?

 

[mikidymac]

Yes you absolutely are. You better check it ASAP or you will seize the rotary gear then strip it and the crankshaft.

There is a fitting on both sides of the lower engine block that supply oil to the rotary gear cavity. You can loop the hoses above the engine and always make sure there is oil in them or even easier to just leave the oil tank connected and keep oil in it.

Again, only API-TC oil.