Also what are your goals? What type racing do you intend to do. On top of that mileage means nothing, it is all about the time on the bike and what you are doing during that time. Some days I will ride an hour and do 12 - 15 miles. Other days I will ride an hour and do 23 miles.

*Note the hour example is for comparisons only. Unless I'm on the trainer it is very rare to only ride an hour.