Your bike's rear derailleur pulley wheels are probably the most neglected part of your pride and joy. A quick way to determine if your pulley wheels are worn out is by checking whether they do not spin as freely as before or by judging how sharp or flat the teeth are - the sharper or flatter they are as compared to brand new ones, the nearer they are to their end of life.
To know which set of Pulley Wheels are suitable for you, simply find out the model number of your Rear Derailleur and select the corresponding pulley wheel from the drop down list.
