How To Set Cable Tension On Rear Derailleur. Check that when the shifter is actuated accordingly the rear derailleur positions the chain on the largest sprocket. Mountain bikes that have more than one sprocket on the rear gear set the rear derailleur plays a critical role.
If the derailleur is rubbing on the outside of the chain you need a little more tension. Many people think their H-limit screw is set appropriately but it turns out the cable pull is stopping the derailleur not the limit screw. 4 Tools to Replace Your Chain.
You can start by putting your bike in a bike stand if available.
If it wont jump down to the smallest then release some tension on the cable using a 5 mm allen key. There are also some situations where the spring tension of the rear derailer. Adjustment of the rear derailleur is sometimes necessary to. I recommend buying only premium-grade cable and housing.
