I recently bought a 2003 WR 450 from a good friend, and the bike has 1400 miles on it. (He never reset the odometer) He is a fairly hard rider but did not race it, and he changed the oil often. So I am wondering how long this bike might last, considering I will be only trail riding with my son, not racing, and I will maintain the bike rigorously. The reason I ask is I just read in Motorcyclist, I believe, a service question, where someone wrote in that his new KTM 250 has recommended top end rebuilds after 20-30 hours. That kind of interval is unacceptable, in my opinion, especially considering how expensive KTM's are. My Yamaha has at least that many hours on it now, and runs like a raped ape. Comments are appreciated. Thanks.