I frequently ride with the local bike club on 18-20 mph group rides. Sometimes I will ride 30 year old bikes, sometimes I ride my newer bike. For all the money those other guys spend on the latest and greatest equipment, they are not that much faster. It is NOT the bike holding me back. Their extra speed has more to do with the amount of riding they do than their bikes.

Spend some time polishing your bike and maybe buy some new tires and grips, it will look like new! Then just get out and ride and stay away from the bike shops!