Don't listen to these guys about engine rebuilds, valves, 
I just sold my 2008 CRF250r. It had probably somewhere around 80 hours on it. It was raced once season by one guy, then I rode it for 2 years. Valve clearance always stayed in spec (0.011 exhaust and 0.005 intake) and it ran like brand new when I sold it. The CRF has titanium intake valves, or the other way around. 2008 also got the Honda Progressive Steering Damper. Honda did real good with the CRF250r in 2008. The only problem that I had with it, was that infamous '08 bog. But that's something you can fix with a leaner needle and a richer leak jet.
If you think you can handle the bike, then it's a give 'er! Remember at your age a 250f will take a lot of getting used to, so dont rush into it. Good luck!
I just sold my 2008 CRF250r. It had probably somewhere around 80 hours on it. It was raced once season by one guy, then I rode it for 2 years. Valve clearance always stayed in spec (0.011 exhaust and 0.005 intake) and it ran like brand new when I sold it. The CRF has titanium intake valves, or the other way around. 2008 also got the Honda Progressive Steering Damper. Honda did real good with the CRF250r in 2008. The only problem that I had with it, was that infamous '08 bog. But that's something you can fix with a leaner needle and a richer leak jet.
If you think you can handle the bike, then it's a give 'er! Remember at your age a 250f will take a lot of getting used to, so dont rush into it. Good luck!
I could agree, I never had valve troubles on any of my bikes except the honda.2006 CRF150F, I rode it like and MX bike for a year then it turns out it just needed an adjustment, but I rode the heck out of that thing. I never had to reset them on my yamaha either. It is good to check them at the beggining of every season but you won't have to worry about the valves just blowing up 
Sorry, I had to
Act like an adult and I'll look the other way, even though I'm supposed to ban/delete your underage account.
