a lot of it has to do with rider skill level as well. Are there blasters out there than can beat a 250r, of course. However, if you take an average run of the mill 250r and pit it against an average blaster, with riders of equal weight and equal skill, the 250r is going to win every time.
In your case, there really is only one way to find out!! Luckily there are so many factors involved that you just may have a chance. Like, if you weigh 160 and your buddy weights 250.....you'll have a good chance!!