I have an '06 450 with 109 Vet ridden hours on the meter. I am the original owner. I have ridden only on hardpack and only a few times in mud--of which I cleaned well. I only weigh 150 lbs and don't feel that I am putting high loads on the tranny and clutch at all--at least it doesn't feel like it. I had a shop install a Weisco top end kit on it and hone the cylinder at 75 hours. They said the top end was is great condition. I have had the forks and shock serviced 3 times. The whole bike is in prisitne condition. I am currently cash strapped for an '11 and have had a few freinds tell me that I don't need a new bike--that my Yami 5-valve has alot of time left on it. Any comments on the hour durability of this bike?