Removing Fork Caps
Easy-off the right way
Removing your typical fork cap isn't exactly rocket science, but it can be a pain in the butt, especially the first time you do it. Since it's an integral part of fork maintenance, here's the 1, 2, 3 on removing (and installing) them without pain.
1. Wrestling with the forks when they're off the bike is a headache 99 percent of the time. It's a lot easier to loosen or remove those caps when the forks are still attached to the bike.
2. Spring preload can make the caps difficult to remove, and damn difficult to install. Relieve the spring pressure by blocking up the bike so the fork hangs freely.
3. Give yourself plenty of room to work. Some jobs, such as replacing the fork springs or adjusting preload or fork oil level, can be done with the forks attached to the bike-but not if the handlebars are in the way.
4. A wrap of masking or electrical tape will protect the fork caps from marring when you put the wrench to them; an old towel should be used to protect the fuel tank and front fender.
5. Most forks have pinch bolts in the upper and lower clamps. Because the upper pinch bolt compresses the internal threads of the fork tube, it locks the cap in like it was welded, so always back the upper pinch bolt off before trying to remove the cap bolt. If you don't, the threads are liable to come out with the cap.
6. To remove the caps, use the appropriate socket and a ratchet or preferably a T-handle to spin the cap out. As you're turning, maintain a slight downward pressure. This will prevent spring tension from overpowering the cap and forcing it up and out when it reaches the ends of the threads. Not all caps are under tension, but those that are can sometimes pop out with enough force to dent your forehead, so pay attention. In most instances, you'll be able to feel the tension on the cap diminish as it reaches the end of the tube. (If the cap gets really loose, chances are good there's no tension on it and you can simply spin it out.)
7. To reinstall the cap, lubricate the threads with grease or antiseize. If there's no preload on it, simply install it and run it like any other bolt. If there is a preload on the cap, engaging the threads can be a little tricky. One way to overcome the spring tension is to place the cap in your socket with the ratchet or T-handle attached and rest it on top of the spring again, bear down and engage the threads; while maintaining down pressure, gently rotate the cap using the ratchet. If the cap resists, stop and make sure the cap is square to the threads. A cross-threaded fork cap is difficult and expensive to repair.
8. Fork caps need to be tight, but not crazy-tight. Tighten them (and the pinch bolts) using a torque wrench.
9. If you remove both fork caps at the same time and the jack drifts, your bike is going to fall over. Either do one leg at a time or make sure the bike is properly supported.