kawasaki 250f or honda crf150r

The KX250F is twice the bike. The CRF150 is about the same as an 85cc 2-stroke. If you're talking durabillity, go green !!! I built a race bike out of an 07' KX250F. Nothing big, just some engine mods. It felt as strong in the top end as a 450. The bike never let us down. We won alot of races. It went about 80 hours of kicking the crap out of it before we had to do any valve work. The only reason that it's gone now, The rider sold it to get money for school.