I read a year or so ago that nobody in the pro peloton weighs more than one kilo (2.2 lbs) per inch of height, and most are around 2 pounds even. I'm 76 inches tall, so i should weigh 152. I haven't weighed 152 since I was a sophomore in high school, and I'm not likely to start now.
For the record, I'm, uh, 80 pounds from the polka dot jersey, and proud to be there from where I used to be.