Hi Jess. I used to ride a carbon fiber, Trek 5500. I'm 6'2" and 330. I developed problems with some numbness issues despite tryinf 5-6 different saddles and then went to a tadpole trike (2 wheels out front and 1 in the back. I went with a catrike expedition, but also tried the catrike 700. If your knees bother you, you can also try shorter cranks. Have fun. Agree with the above knobby tire comment.

Tom