How to Adjust the Back Derailleur on Your Mountain Bike for Optimal Performance
To adjust the back derailleur on a mountain bike, first shift the chain to the smallest rear cog and the middle front chainring. Next, loosen the derailleur cable anchor bolt and adjust the high limit screw until the chain is aligned with the small cog. Then, shift to the largest rear cog and adjust the low limit screw until the chain is aligned with the large cog. Lastly, pull the derailleur cable taut and tighten the anchor bolt. Test ride the bike and fine-tune the shifting as needed.