How to Change the Bearings in a Rear Bike Hub

The wheels of your bicycle are, in a sense, what make the bike functional. The bearings allow the wheels to roll smoothly around the axle that connects them to the bike frame. But if the bearings in the wheels of your bike--especially the back wheel--are broken or otherwise not working correctly, the effort required to move the bike will be greatly increased, and the pleasure of riding your bike will be greatly decreased.

Things You'll Need

• Freewheel extractor
• Chain whip
• Cone wrench set
• Flathead screwdriver
• New ball bearings
• Bicycle bearing grease
• Adjustable wrench

Instructions

Removing Rear Wheel Bearings

1. Remove the rear wheel from your bicycle via quick-release or an adjustable wrench.

2. Use a freewheel extractor and chain whip, which can be found at your local bike shop, to remove the freewheel from the hub. Hold the chain whip on the freewheel to keep it from spinning. Place the freewheel extractor in place and use an adjustable wrench to twist the freewheel free.

3. Place an adjustable wrench on the end nut of the axle, and a cone wrench on the cone nearest the hub. Twist the end nut to the left while holding the cone in place. Remove both the cone and end nut.

4. Remove the axle from the hub by pulling it out the side that still has the cone and end nut attached.

5. Use a flat head screwdriver to remove the bearing protector from each side of the hub. Be careful not to dent or otherwise damage the bearing protector.

6. Remove the ball bearings on each side of the hub by hand. Do not discard them, as they will be useful in determining the correct size for the new wheel bearings.

Installing New Bearings

1. Inspect the inner bearing race on both sides of the hub for pitting and scratching. If the bearing races are worn out or damaged, the hub will need to be replaced.

2. Apply a liberal amount of grease to the bearing race on one side of the hub. Place the new bearings in the grease so that they do not fall out. Be sure to use the correct number of bearings for your hub. Most hubs require eight or nine bearings.

3. Reinstall the bearing protector and the axle with the cone facing the new bearings. Place the wheel sideways on a desk or work platform to prevent the bearing from falling out when working on the other side of the hub.

4. Apply a liberal amount of grease to the remaining bearing race and set the new ball bearings in place. Reinstall the bearing protector and axle cone.

5. Twist the end nut onto the axle loosely, pick up the wheel by the axle and spin it. Check for side-to-side play in the hub and unnecessary resistance to spin. If the hub is too loose, tighten the cone until the play disappears.

6. Place a cone wrench on the cone and hold it in place while tightening the end nut with an adjustable wrench.

7. Use a chain whip to reinstall the freewheel on the outside of the hub. This does not need to be too tight, as pedaling the bicycle will tighten the freewheel.

8. Reinstall the wheel on the bicycle and take it for a test ride.

References

• The Big Blue Book Of Bicycle Repair