Top 3 Reasons For Trading Up To A New Bike By: Tim Oswald | - There are several reasons to trade in your old bike for a sparkly new one. It may be that ones old bike is simply worn out and in need of replacement. Alternatively, it could be that a new bike has a better design and features. Finally, it could be that a new bicycle is more suited for certain purposes, like mountain bikes for off-road trail riding.