The 250 Ninja is a good starter bike. There a a few "upgrades" out there for it (pipes,jet kits). You'll get some more speed but not a whole lot. there aren't any "locks" or anything like that on the engine besides the rev limiter which if I remember right kicks in somewhere north of 14,000 rpm. Look for a good used one that way if you decide next year to get a bigger one you can probably sell it for what ya got in it. Here is a great site for the 250's. http://faq.ninja250.org/wiki/Main_Page