I'm looking at getting back on a 4 stroke. I've been riding two strokes ( ktm 08 300sx and 06 yz250) for the last few years. I've found a very clean 08 450 with under 15 hours on it. I was going to pick it up today. That was until I read about the timing change issues. Is this a real problem? If so should I look for another year? I don't a fuel injected bike. I'll be using it for offroad and light mx. I can split the case and rebuild the four strokes, but I rather not. My boys race new 250f's so I've spent plenty of time making their engines right. I just want a play bike that has enough motor for an occasional dune trip.