you probably could, but the top tubes on most flatland bikes are between 18 and 19 inches, whereas the top tubes on most street-oriented bikes are between 19.75 and 21 inches. the top tube is where most of your leverage is going to come from for jumping and manuals and other tricks. so a longer top tube SHOULD equal more leverage, unless you're too small to get your weight in the right place, 5'11" isn't too small at all for a 20.5" frame. that's a good size for just about anybody as it's manuverable and long enough to give you good leverage.
i'm pretty sure that nowadays most serious "freestyle" bikes (flatland, vert, street) have 14.25-14.75 inch chainstays. mine has a 14.25" chainstay and a 20.65" top tube. i thought about getting a bike with a 20" top tube for a while because i figured i'd be able to toss it around a lot easier and suck it up under me for bunnyhops and icepicks and manuals and stuff, but i won't know until i try out a frame with my parts set up, and i'm not sure if i want to drop $250 on a new frame if it's not going to work out for me. i'd say the best plan is to go out and ask to try out your friends' bikes and ask what the measurements are on them, if they don't know, then bring a small tape measure with you, or look it up online later at the company's website.
right now i have a terrible one barcode and the frames i'm looking at are the standard lengthy, the mutiny punisher, or the dirt brothers patriot just because i like the star cutout on on the chainstay gusset. but i'll probably just end up keeping the barcode.
Last edited by OneTinSloth; 07-09-03 at 01:13 PM.