Bicycle Derailleurs are essential in bicycles with a chain. To move the mechanism from one sprocket to another, a Bicycle Derailleur is what you need. The change in chain tnesion is managed by the bicycle derailleur as it moves the chain onto different sprockets.
For the ones who are looking for the best bicycle derailleur, BikesXpress is where you can find one at economical prices. Contact our experts with any questions.