I'm no expert, but I have owned many PWC and several SEA-DOOs including a 99 GTXRFI.
The Non RAVE equipped motors used the dino oil. Your motor and the 951 that I have use SYN. There is a great deal of controversy about these oils, specifically the SEA-DOO XPSII which is approved for thier injected motors also.
BTW be acreful with recomendatiuons for "injetor" oil just because your motor has injection in the title. Rotax has actually had two types of 'injection' the type you have "RFI or Rotax Fuel Injection" by Bosch is more like a throttle body, much like GM v8's and is no longer used.
The newer "DI" or Direct injection by Orbital has injectors mounted in the head and the fuel is injected directly into the combustion chamber.
the lubing requirements are actually quite diffrent and have to do with the oil atomizing in air vs air fuel mixture, etc. The DI motors also have a third piston that has to be lubed.
Bottom line.
I will give you my opinion. Based on the fact that you have the very strong very reliable 800 motor and it is stock I would say that you can use a less expensive oil. Not a less expensive type of oil. It is critical that the use an oil sepcifically designed and formulated for your application. TWC3 oils are designed for outboards, not PWC.
I will rank my choices by price.
#1 And most expensive is the XPSII $37 gal
#2 Mobil MX2T which is now called 2R or R2, I can't remember. It is slightly less than the XPS at around $30 gal.
#3 Amsoil, Interceptor. Not Dominator racing oil(dirty) and not the Injector oil. Around $20 a gal.
I have a Stock 951 Injected Rotax. I got a good deal on 15 gallons of XPS so I run that exclusively.
I also have a slightly modded 951 that run the Interceptor in.
That motor with good oil and clean fuel will run for a very long time.
There are several good threads on this forum about this topic. I started one about the API rating and good some very good info.
Do some more research and you will come to an educated decision that you can feel confident about.
[ July 01, 2005, 06:03 PM: Message edited by: Gypsy ]