this frustration I'm having with my bike. The tires can only hold 185lbs, and I keep bursting the back tube[/QUOTE]

Congrats on everything, but the thing about your tubes bursting jumped out at me. Are you trying to pump your tires to 185lbs? Because your weight isn't enough to burst a tube unless it is way over inflated. Most tires need to be pumped only to 80 lbs. The pressure range should be printed on the side of the tire.