I have owned Rotax engines since 1985. I started with a 521 rotax in a 1985 Formula Plus Skidoo snowmobile, then proceeded to own about twenty Skidoos over the years all were oil injected. None ever failed due to the oil injection. However the stinky smoke would give me headaches. Plus the added expense for two stroke oil. They also have a shorter life cycle due to their power band from high rpms. They also are harder to start when cold.I'm looking at buying one of two different 2002 GTX's. One has the 951 DI with 50hrs and the other has the 4Tec 155HP with 80hrs. THey are both priced within a few hundred dollars and appear to be in about the same good condition. I would like to know from anyone who has owned similar models with both engines which they preferred. I'm leaning towards the 4-tec unless anyone can persuade me otherwise.
Now I have abandoned snowmobiling for jet skis and a 29 ' perfomance boat.
As far as the 4tec is concerned I own three with superchargers. Much nicer and more bottom end torque. Less to operate and maintain. The closed loop cooling is better.
You would be getting the non-supercharged GTX which is the best pick. It has a strong engine with no supercharger to worry about. You would be taking a step backward in technology if you bought the two stroke. It is very quiet, my GTX 215 is so quiet you can't hear it at an idle.
Even though the two stroke has less hours the 4 tec will last longer with very little maintainence.
See Ya :00000048: