I'm a BBW 5'8 280 the dude I been messing around with is 5'10 maybe 180 our sex life is pretty good but I want to please him more. he wants me to ride him we do every other position but cow girl my ex was a big guy so I had no problem bouncing up and down on him you see I can really get into it and get a little rough and I'm scared I'm going to hurt him plus I have bad knees lol so there is no real support when he under me and I start feeling insecure ...IF ANY ONE HAS ANY ADVICE ANY HELP WILL BE HELPFUL