Suggestions for starting bike

Hey y'all, I am looking into getting into mini bikes. Currently, my budget is around $1000, but I can save up more if needed. My problem is I am a bigger guy, about 6'2, 290, (my girlfriend says I wear it well :)), but most of the bikes I'm looking at have a 220-240 lb weight limit. What are some bikes that I don't have to mod a lot, to get some good speed and enjoyment out of? I am also willing to learn how to mod them in the future. Currently, I have my eyes set on the Axis M200, which I can get from my local Lowe's, or the b200r from Coleman sports which I can get from a nearby tractor supply co. One thing I want to do in the future is mod the bike, and learn more about bikes in general, so I want to keep that in mind when purchasing one. Thankyou all!