I have looked at some of the newer Kawasaki motorcycles to see about converting one of them to a bobber motorcycle. Below is a 2012 Kawasaki Vulcan 900 motorcycle, I think it would make for a great bobber motorcycle. I would only have to make a few changes to this motorcycle. I would toss the front fender or sell it on ebay. I would also get rid of the seat and rear fender. I would change out the seat fo a tractor motorcycle spring seat and chop and change the rear fender. I would get a few old lights to mount on each side of the seat for tail lights and move the license plate to the belt drive side of the frame.
I would keep the long pipes but I would cut the baffles out of the motorcycle pipes to make them louder. Keep in mind that states have rules on how loud pipes can be and though they are rarely enforced, the cops that do are jerks about it. I have a few friends that are cops that have louder pipes then I do and do not care about it. Just be careful and know the laws in your state and city.
I really like the flat black look of the bike with the orange paint job. I hate chrome as you have to keep it really clean and it takes a ton of effort to keep the chrome clean on a motorcycle.