I've been riding pretty regularly for a couple of years but I've never been comfortable climbing standing. It just seemed unnatural, clumsy and fatiguing, so I would always sit and spin the way I was intended to do. Lately I've been trying to learn to climb properly and stand whenever I can on a hill. I'm a little smoother and can go a little longer. I currently weight 260 lbs.
My question for the heavy riders: do you climb standing? Any problems with cranks, bottom brackets, wheels, spokes, etc?
Sheldon Brown warns that this way of riding stresses the bike more and can cause sudden and dangerous component failure. I believe that and and I try not to stress things too much, but it's kind of fun to thrash up a hill and throw the bike around a bit!