300lbs

I've been wanting to get a dirt bike ever since I was a little kid, now I finally have the money just my problem now is my weight. I'm between 300-350 lbs. I don't know a lot about max loads on dirt bikes so I'm hoping someone here could help me out.. I'm 6 ft tall aswell. Is there any sort of...

Does anyone know the SUV weight in tonnes, please?

I've been working out for about 4 months now. i've been doing more weight less reps and am trying to build up to bench a lot more untill i can bench at least 300lbs. I am currently bench pressing 165lbs. How long will it take for me to get there from this point if i keep up my workouts ?

Would this bike be ok for someone who is a few lbs over 300? http://kansascity.craigslist.org/bik/1017538430.html Really for exercise/riding around neighborhood.