Your butt is gonna be sore for awhile if you just started riding. If the bike doesn't fit you well, it will also cause you some discomfort. Best thing to do is to ride for a while and let your butt toughen up a bit, while also ensuring that the bike is set up well for you. Your local bike shop, where I suppose you bought the bikes, should be able to help you get them adjusted properly. Of course you may have to make some small adjustments yourself as you ride more...to get it just right for you.
If, after adjustments and a few weeks of riding you are still uncomfortable, then you can start shopping for new saddles - some of the saddles that come on new bikes are just plain junk. In my opinion, you can't go wrong with a Brooks B17 leather saddle.
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"Let us hope our weapons are never needed --but do not forget what the common people knew when they demanded the Bill of Rights: An armed citizenry is the first defense, the best defense, and the final defense against tyranny. If guns are outlawed, only the government will have guns. Only the police, the secret police, the military, the hired servants of our rulers. Only the government -- and a few outlaws. I intend to be among the outlaws" - Edward Abbey
Last edited by chipcom; 12-19-06 at 09:21 PM.