How To Overhaul a Threaded Headset

Applies to regular 1″ and oversized 1 1/8″ threaded headsets.

• How To Check If Your Bearings Are Worn
• Wheel Removal and Installation

If you ride your bike a lot, you should overhaul your headset at least once a year to check for wear and to make sure the bearings have enough grease.

Required Tools

For this tutorial, you’ll need some waterproof grease, an old toothbrush and some cleaning solvent. If you have an older 1″ headset, you’ll need a set of 32mm spanner wrenches. Larger 1 1/8″ headsets usually require a set of 36mm spanner wrenches.

Brake Cable, Wheel and Stem Removal

Before you begin, you’ll need to disconnect the front brake and remove the brake cable from the lever. You’ll also need to remove the front wheel. To remove the stem, simply loosen the stem’s tightening bolt far enough so you can give it a light tap with a hammer. This will knock the inner wedge loose and allow the stem to slide up out of the fork.

Headset Disassembly

Now loosen and remove the locknut. Holding the fork in place with one hand, remove any spacers and unthread the adjusting race. Make sure to note how many spacers there are, and what order they came off. Gently slide the fork down and out of the frame. Make sure to make a note of which way the bearing races are facing before you remove them.

Headset Cleaning

Wipe clean all of the bearing races located on both the frame and fork as well as the upper threaded race. Inspect all four of the bearing races to make sure they are not grooved or pitted. If so you will likely have to replace the entire headset unit.

Thouroughly clean the ball bearing cages with your toothbrush and solvent. Then wipe them dry with a clean rag, and set them aside to air-dry. Inspect the ball cages to make sure they aren’t bent or worn. You can replace the cages without replacing the entire headset, but you’ll have to bring the old set to your local bike shop for proper sizing.

Headset Greasing

If all of your parts are ok, apply a layer of grease to all of the bearing races. Then install the ball cages the same way they came out and add another layer of grease on top of them.

Headset Assembly

Once the bearings are in place and fully greased, carefully slide the fork back into the frame and finger-tighten the adjusting race. Wipe off any excess grease that may have squirted out the sides. Slide the spacers back on and thread the locknut on finger tight.

Headset Adjustment

To adjust the headset, hold the lower adjusting race with a spanner wrench and use a second spanner to tighten locknut against the adjusting race.

To test the adjustment, check that the headset turns freely and check for play by rocking the fork back and forth in the frame. Re-adjust as needed until the bars spin freely and have no play.

Brake Cable, Wheel and Stem Installation

Reinstall the front wheel. Before reinstalling the stem, coat the shaft and wedge with a thin layer of grease. Then reinstall and tighten the handlebar stem, and reconnect the front brake.

Final Adjustment

Then re-test the headset adjustment by making sure the bars spin freely, and using your front brake, rock the bike back and forth to double check there is no play in the headset.

Resources

• Headset Service (Park Tools)
• Servicing Bicycle Headsets (Sheldon Brown)
• More Headset Info (Bicycle Search)

Repair Guide » Bearings, Fork, Grease, Headset, Lubrication, Stem