Wow. There is a lot of complicated answers comming from this thread. I don't think it's that tough. If you know your BMR, just start counting calories in all the food you consume. If you hit your BMR on a day that you don't bike, stop eating. After a couple of weeks, you should have a good idea of appropriate portions and it gets a little easier. Deny yourself nothing, just keep the portions reasonable. I think a well balanced diet with a calorie cap is a lot healthier than trying to cut out entire food groups, unless you have a specific goal other than simple weight loss. I enjoy food too much to say I'm going to cut out bacon, cheese, bread, ice cream, whatever. I've been adhering to a strict calorie deficit diet since early February and have been consitently loosing ~2lbs per week without skipping dessert.

Get a heart rate monitor that counts calories or a power meter of some kind. My HRM would indicate that a strong pace on the bike is worth 18-21cpm (1080-1260cph). I'm not sure how accurate this really is, but it's consistant and it's what I have.