I used to ride on a few different MX tracks on my old Banshee ....not all the fancy tricks though, but used to jump upwards of 30 - 40 ft on a stock suspended quad....I was in a lot better shape / lighter back then ( early 20's / 180 lbs ) too though !!
My biggest problem was not enough traction or suspension to clear some of the jumps, and the landings were harsh, I bottomed the shit out of it all the time, ( actually thought I was gonna break the frame at times..LOL ).
However I did break the stock pipe mounts and the stock pipe mids fell off a couple different times.
I was never a Super great rider, but was alright, could pass some guys on 2500cc bikes...back in 2001 or 2 maybe.
Mike