What made the original Excite Bike so great was it's simplicity. There were only 4 rows you could drive in and only two speeds to choose. All you really had to worry about was avoiding mud and overheating.
Excite Bike was recently remade, for the Nintendo 64. You could still create your own tracks and all, but it really isn't anything above the gazillion other motocross videogames that exist.
However, you can unlock the original Excite Bike, which is actually more fun then the afore mentioned gazillion games. All you have to do is finish first in the Challenge Round of Pro Season.