SInce no one else has answered your question, I will give it a shot.
"I have a question. Since riding the bike 30 minutes a day, at least six days, sometimes seven days a week my weight loss has plateuted. Anybody have any suggestions."
A couple of things might have happened.
1. You most likely (indeed almost for sure) have built up considerable muscle, and now your weight is composed of a much higher percentage of muscle, which you don't want to get rid of.
2. As a result, you likely burn calories more efficiently, and have more muscle with which to propel yourself. Therefore, you are not burning as many calories per mile or hour as you used to.
So, eat less calories and exercise more. And add some other types of riding - intervals, hills - anything different to challenge new muscle groups. Or, perhaps you are or could be happy with where you are now?
I am sure others will have aditional comments. 
Last edited by DnvrFox; 07-09-08 at 05:35 AM.