I started riding trials quite recently, like a few months ago and am finding 20 inch great for learning on although im not 6 ft, so dont know how it would be on a 20 incher for someone as big as that. i have seen a pretty big guy ridin 20 inch though around where i live and it didnt look to bad... Try looking on ebay and places like that for second hand bikes, i built up a t pro with maguras on it for around 250 by buying most of it from friends second hand. good luck!