I don't post to this forum but I had to since I swear by this cream for sores. PINXAV.com pronounced pink salve http://www.pinxav.com/
I used this on my daughter when she was a baby and I swear by this. Trust me I put alot of miles in doing 12/24 hr bike races and ultri tri's. I've gotten some pretty nasty chaffing/sores and the next day they are just about gone. Of course this is pink, but its worth the discoloring of your panties, just wear a dark color. I have also used this for chafing by the underarm from sports bra, and wear thighs rub togther.
I find for really longer rides I like less padding. I get less sores with a tri short then regular shorts for some reason. some day a 4 hour ride irritates me while a 7 hour ride I have no bottom problems.
Make sure you lube up often. You may have to reapply more depending on how long you ride. I use Chamious Buttr, I know some people use Bag Balm. Sometimes its just trial and error