Do you have the diaper opened up to the largest size? I still have A on the medium size of the BGs at 17 months, and I think the FBs are similar in size. It should not fit like a Speedo!
I guess b/c my only experience is with sposies I'm not sure how a CD is supposed to fit. He is in a size 6 (sposie) and they come up over his belly-button. I had the FB on the biggest setting but it seemed kind of loose like it might sag and it was just under his belly button already. I cinched it up a bit because I didn't want it bagging in front during the night---you know w/boys you gotta have as much protection up front as you can! I am ordering some BG 3.0s on Friday with a few stay dry doublers, too. My goal is to get him in cloth all day at the sitters by the end of November and then I'm going to do prefolds and covers when he is at home with me on the weekends and at night. Q: is hemp more absorbent than microfiber??
On a side note, my secretary (who is also one of my close girlfriends) gave me SO much crap when I decided to convert to cloth a few weeks back. She just came into my office and told me she had been doing a bunch of research and she thinks she is going to try it, too. She is 16 wks prego. I was like !