The biggest and most expensive one you can find!
you should get a 80-125
Depends on weight/height. At thirteen I rode a 125 4stroke trail bike and an 85 two stroke racebike
CRF Or YZF 450 is a good choose.... not the x models the not a high strung...
For a 13 year old it depends on your size and your experience with dirt bikes, but an 85 is usually the best size bike and fastest for a 13 year old. Unless you are really tall which you would need a 125.
Try a Yamaha TTR 125 or CRF 150 (not the motocross version).
you should get a 250 trust me i am 13 and 120 pounds and 5' 5" i ride a 250 and it is a perfect size for me. dont get an 85 because they are way to small
19753
Yamaha XT250
Yes
Yamaha
it depends on how tall you are if your somewhere between 5.3 and 5.5 you should get a 125cc but I can ride a 125cc and im only 5.1 it just depends on how good of a rider you are.if you between 5.6 and 5.10 you should get a 150cc dirtbike.If your 5.11 or taller you can ride any dirt bike you want.
Kawasaki Kx500, any year will do, but the best bike for a beginner is a Yamaha yz490