I have an 03 WR450 that has all the mods including mostly YZ motor internals that I ride alot of single track and general off road with. I don't ride competitively, so weight is not a concern but long life is. I spend too much time working on my kids race bikes to spend much time and money on mine. It's time for a new set of sprokets and chaing for the WR and I'd like some input on which type of chain to buy - standard, O-ring, X-ring, etc... I'm really not sure in my case what would be the best choice. The conditions around here vary from rock to sand to clay and everything inbetween. Any help would be great.