Headset Replacement

In rare instances you might need to replace the headset cups in your frame. The cups can become pitted, making the steering feel notchy. You can sometimes get around this by removing the ball bearings from their retainers and adding extra ones so they completely fill the cups. Otherwise you can buy a new headset and install it. First you need to remove the fork (see my previous post):

I used a 10mm wrench to remove the brake so I could get to that crown race. The headset pieces are not always interchangeable, so I like to replace everything as a complete set. The fork crown race comes off with a hammer and punch:

Give it a few taps while alternating on either side of it. It will eventually slide off. Next I use a section of 1" PVC pipe to seat the new race into position. It's a press fit, so make sure it's fully seated:

Now comes the really fun part. You need a special tool to remove the cups inside the head tube. You can spend some money for a special headset cup remover. I'm fairly handy, however, so I just made this out of a piece of 1" electrical wire conduit:

I used an angle grinder to make 3 cuts at one end, then spread them apart a little bit with pliers:

It seems to work pretty well. Next you slide the tool into the frame and hammer the cups out:

You'll probably have to hit pretty hard, so make sure the frame is well supported (I just hold it in one hand while striking the tool with the other). Repeat for the other cup. Now set the new cups into position, then press them in:

If you don't have a big vise, a bike shop can usually do this step for cheap. The important thing is to center the vise jaws on the cups, and press them in straight until they are fully seated. Finally, just pack the bearings with grease and reinstall the fork. Again, not all headsets are compatible with all forks (especially on really old bikes) so good luck finding the right replacement!

Headset Overhaul

I had nothing interesting to do today so I thought I'd do some winter bike maintenance. My old Dawes always had a clunky feel from the headset bearings, so I thought I'd try to fix that. I first loosened the handlebar stem bolt:

Next I loosened the top nut on the headset:

 

The front brake cable was just barely stopping me from removing the handlebars, so I unhooked the straddle wire for more clearance:

Bars, top nut, and cable bracket removed:

Carefully unscrew the top race. On most bikes the ball bearings are held in retainers, so they don't all fall out when you service your bike. Not this one. It helps to hold a rag or paper towel by the bearing cup to catch anything that falls out.

You can slide the fork straight out after removing the top race:

Now clean all the headset parts and repack the bearings with marine grease:

The lower cup gets exposed to rainwater, so that's why I recommend some kind of water resistant grease. If you have fenders or never ride in the rain then use whatever grease you like. Now you can reinstall the fork:

Screw on the top race, then reinstall any spacers, brackets, and the top nut in the same order that you removed them:

Now you can reinstall the bars and dial in the bearing adjustment:

Use the top race (in this case, the round piece with the knurled finish) to set the preload, then tighten down the top nut to lock in the adjustment. Tightening that top nut might increase the pressure on the bearings, so screw in the top race until the bearings have a very small amount of play first. Then tighten the top nut. The fork should turn easily without play when you're finished. It's difficult to get the adjustment right the first time, so keep trying until it's perfect.