To replace the inner tube of the rear wheel of the bicycle, first screw down the nut fixing the axle and take down the wheel; The specific operation steps are as follows:
1. First screw down the nut fixing the axle.
2. Take the wheel off.
3. Press the valve firmly to bleed.
4. Use a crowbar to reach into the gap between the outer tire and the rim.
5. Then extend another crowbar into the gap between the outer tire and the rim and pry it down.
6. Take the inner tube out of the outer tube.
7. Install the new inner tube back, install the valve first, and the operation is completed.
