Whats the perfect begginer learning bike??

im lookin at the ninja 250 but a lot of my friends are telling me imma get bored with it quickly..i know how to ride a dirt bike and quad but ive never ridden a street bike b4..im 5' 8 160 lbs. any suggestions?

Trust me on this; the 250 is too small. I used to own a Honda / Suzuki / Kawasaki store and now build bikes on my own. The ideal first bike is an older (don't buy new) Suzuki GS-500, Kawasaki Ninja 500 or 600 (the five is lacking in alot of key areas) or the Katana 600 (or even the Katana 750, since the power plant is under-powered by today's standards but still fast enough to really scare a newbie). These bikes can be purchesed cheaply second-hand, they will grow with you as you improve (you won't outgrow them in six months) and you won't care if you drop it a few times. Once you have been riding a year or two, look into getting th bike you really want (you'll know what it is by then). Until then, ride the cheapest 600 you can lay your hands on and learn all you can. Take the motorcycle safety course in your city; it will save your life.

Keep the rubber side down and enjoy the ride!

u should look into a 500 or 600, its only as fast as u wanna make it. just trying to help.

Start with the 250. You will get beaten of at first but you will become a better rider. When you can ride the 250 fully (meaning you can hurt it without it hurting you) then go bigger. By that time you will be a better rider than those who started on the big bikes.
You have got some experience so perhaps you could start on a bigger bike but in saying that what size was the dirt bike you rode. I'll bet it wasn't any bigger than a 250 if it even was that big.

I would go with either a JR50 or PW50. Both are available with training wheels.