A wider tire isn't going to hold more weight. The most you can do without modification is to fill tire to the maximum recommended pressure and set the two shocks that are underneath the bike to their firmest setting.
hey im a fatty, ol is close 2nd an i ride a stinkin, regular old standard shocks, rides like a hard tail, softail kinda scoot she bottoms out a lot (ya ol too) he he he we keep on going .
let a lil air out it,ll ride smoother.
There's a guy I used to work with that had a Honda VTX 1800 with a car tire on the back.....was the one and only time I've seen someone with a car tire mounted on a bike...he was a slim and trim 350 easy, the tire looked like it belonged on a CIVIC....wish I had a picture to share....haha
Im not hating on anybody who is fluffy, this just reminded me of this guy!