I was about 260 when I started riding. Flats were fun but hills hurt, 1/2 mile climb was murder. I was told that I'm not supposed to climb cause I was big.
If someone says I can't, I usually do it cause I don't understand "can't"!

...so now I do!
Started riding at 260 lbs. Believe me, riding and climbing are much better at 230 lbs.
6'1 260 lbs
230 lbs...I do miss my biceps though!