Threaded Fork Installation

The new fork arrived. The steerer tube (the tube that the handlebar stem fits into) was about 2 cm too long, so that needed to be cut down. Other than that everything could be transferred over. If your original fork was a perfect fit for your bike, you can simply compare the steerer tubes side by side to see if the new fork is the correct size (too big is ok, too small is bad). I decided to install the fork, and then measure it with the headset in place for better accuracy. Here is the link to my previous post about removing the old fork.

First I had to transfer the crown race over from the old fork. I used a 12" long socket wrench extension and a hammer to tap it off the old fork. You could also use a big flat bladed screwdriver or a punch. Gently tap it little by little on each side until it eventually falls off:

 

Now the race needs to be installed on the new fork. I used a 2x4" piece of wood to brace the new fork underneath the steerer tube. Next I slid the race on, then used a 1" diameter PVC pipe and a hammer to drive the race into its seat. If the race isn't seated properly the headset will loosen up later on, so give the pipe a few extra taps to be sure (the sound will change a little once it bottoms out):

 

Next I reinstalled the bearings into the frame cups. The grease should hold them in place:

Now I slid the fork through the frame and screwed on the top race to hold it in place. I added the rest of the headset pieces, and marked where I needed to cut it (about 2 mm below the top of the locknut). I then removed the fork, clamped it in a vice, and used a hacksaw to cut it to size. I also used a grinding wheel and a round file to clean up the threads. Here is the cut fork:

 Now it's time to install the top nut and adjust the headset. The top race should be screwed on finger tight, then the top nut should be tightened down. The top race should be supported while tightening the top nut, either with a headset wrench, or with my stupid vice grip method:

 

After tightening the top nut, make sure the fork spins freely with no play. Headset play is the most annoying thing ever, so I prefer to adjust the bearings with a tiny bit of drag rather than have them loosen up later. If the headset keeps getting loose I'd use a little blue locktite on the fork threads to keep the race in place. Here is the completed headset:

Now you can reinstall everything that was attached to the fork:

I ended up having to change the front brake, so I can show you a quick way to adjust the cable. This brake has a barrel adjuster, some bikes might have the adjuster on the levers or on a bracket in the headset. Unscrew the adjuster most of the way out, then press the pads to the rim. Bolt down the cable while holding the pads, then screw the adjuster back in until the pads are a desirable distance from the rim:

All you have left to do is align the handlebars and check the bolts to be sure they're tight. This really isn't a big job as long as you have the right tools (and the right replacement fork...). You will definitely need a wrench big enough to fit on the locknut, a hammer, a 2x4, a cheap piece of PVC pipe, as well as a saw or cutting disc to cut the new fork (if needed). A damaged fork doesn't need to be the end of a bike after all.

Threaded Fork Removal

I heard a creaking noise while riding my bike today. The bike has decent parts on it and I assembled it all myself, so I really couldn't figure it out until I saw this:

 

 One of the fork blades has a hairline crack in it. Time to get a cromoly one. In the meantime I thought I'd do a little tutorial on how to swap out a damaged fork. In the next post I'll also show you how to adjust the bearings that hold the fork in place. Anyway first you should remove the front wheel. Next remove anything else attached to the fork, like brakes, computers, racks, fenders, whatever. Road caliper brakes are held on by a nut on the back of the fork crown. Cantilever/V-brakes have a bolt on the front side of each brake arm. Disc brake calipers usually have 2 bolts on the side of the fork blade. You also need to remove the handlebar stem:

I didn't have to remove any of the cables, which is nice. Now with everything out it's time to remove the fork. For a threaded fork you do this by unscrewing the headset locknut and top race:

This is most easily done with a big adjustable wrench on the top nut while holding the top race with a headset wrench if it has wrench flats. This bike's top race doesn't have wrench flats, so I use a vice grip with a towel wrapped around the race to hold it in place. The towel protects the finish from the jaws of the vice grip. With both of these removed, the fork can slide out:

 

Keep track of any spacers, reflector brackets, or cantilever brake cable stops that might also be sandwiched between the two nuts on top. Once the fork is out you should pull the ball bearings out of the headset cups, and clean the bearing surfaces:

I'll show you how to install a new fork in my next post. I bought this one used. Never again.