As a rider for over half my life, I can not say what is perfect for you, only for me. What I can tell you to do is to take the motorcycle safety program. There should be classes in your area and passing their basic course qualifies you for the DMV endorsement. They will provide a 'learner' bike for you, usually a nighthawk 250 or something similar.
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Once you've taken the basic course, and you pick up your own bike, call them back up and take the advanced course. That one requires you to take your own motorcycle in and you'll get to roll through a bunch of exercises in a controlled environment with the hope that, should you ever need to use those moves, you'll know what to do.
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One thing: motorcycles are single track vehicles. They do NOT want to stay upright. Plain and simple, the laws of physics only work because you're on it making it stay up and adjusting it to stay balanced and trimmed. If you are drunk, you will fall. Do not ride while impaired, EVER. Wear proper safety equipment (leather coat, gloves, helmet, jeans and sturdy boots). As fun as riding a bike is, it's also a dangerous form of transportation because of all the a$$hat cagers who will not look out for you. Stay out of their blind spots and always keep your own visibility in mind as well as an escape; braking and stopping is a panic move. Don't panic.
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Lastly, on he choice of a bike, I will say that I started street riding at 16 the day after my pedal bike was stolen. I had a 500cc Virago and now, 16 years later, I'm on a 650cc VStar and contemplating a move to an 1100cc VStar. I like the star line due to their ease of maintenance and you can do a lot of the work on them yourself. Some bikes with water cooling and fuel injection can be difficult to work on unless you have the proper tools and training so keep that in mind as you shop around. Check out what other people are saying about the model you've chosen and give it a test ride before you buy it. If it doesn't put a grin on your face or it doesn't feel right, then it's not for you. Some old friend of my father's from the Angels told me that "the bike picks you, not the other way around," and that's true to an extent.
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Good luck and remember that the SHINY side stays up.