I was reading up in dirt rider about the new WR 450 and they said yamaha kept some of the goodies like the rear 18" rear wheel and bla bla. I'm relatively new to motoing so why is that a goodie as they say? What is the advantage to having a smaller tire in the rear rather than the bigger rear that the YZ sister has giving more clearance (or does it)? And on another question I have, in that same article they claimed that they kept the wide-ratio five speed. However on Yamahas website they advertise a constant mesh 5 speed for the 07 WR. Who had the facts straight yamaha or dirt rider? What does wide-ratio mean compared to the yz-f trans, and what in the world is a constant mesh transmission?