No announcement yet.

Replacing Fork Caps

  • Filter
  • Time
  • Show
Clear All
new posts

  • Replacing Fork Caps

    Replacing Fork Caps
    by various riders

    June 6, 2000 - In a recent thread on the XS list there was a lot of discussion regarding techniques for replacing XS fork caps. This is a necessary step any time you have the forks open for changing springs or changing fork oil. Read through these and form your own opinion before proceding to dismantle your forks

    For changing fork oil WITHOUT removing the fork caps, see:
    Fast Fork Oil Change

    Jemison Richard

    Trick to reassembly

    The trick I use is go put the forks in the triple tree with the front end off the ground (I put a jack under the engine while the bike is on the center stand. On the SECA I put the jack right on the filter housing).

    Now I turn the front end to the left (I'm right handed so my best arm is over the tank). Put the spacer in, put the nut in the palm of your right hand (switch the above around for lefties) and push down. You have to "feel" for the threads. When you feel them, twist your hand to the left until you feel the threads drop, then turn right.


    Of course once you've got a thread on, screwing it the rest of the way is easy. Now, Once I've got one fork done, I swap forks in the triple tree so the other fork is again on the left side. I then repeat the above process. After both caps are on I put the forks in the tree correctly. A little forthought will have the forks in the right place when you put the second cap on.

    The real trick is getting enough movement to get that first thread. Once you have it you're home free. You'll have to try the above method and learn for yourself how to get the first thread. Once you've done it you'll know exactly what I'm trying to say when I say - ".... You have to "feel" for the threads. When you feel them, twist your hand to the left until you feel the threads drop, then turn right."

    Good luck!

    PS: I've had the forks open and shut over 10 times on my SECA and have used the method on numerous XS750/1100s (I'm pretty much a Yamaha guy!) Also, FWIW I have used the 17mm hex wrench also with success but I like the palm of the hand method better (more control).

    If you have a lot of pain in your you might wear a glove but it is going to affect your ability to feel when you have the threads lined up.

    For new caps - try a salvage yard. Or you can take a small machinists file and clean up the threads.

    Dan Lewis

    1. Get the front end off the ground. it helps.

    2. hold the cap firmly - left hand->right fork or right hand->left fork

    3. get the cap in position over the tube.

    4. start with your hand twisted as far left as possible.

    5. close your eyes

    6. grit your teeth

    7. think happy thoughts

    8. push down and twist right for all your worth.

    Repeat steps 3 - 8 as necessary.


    When I screw on my caps i jack up the front of the bike off the ground so the forks are fully extended - at that point there is very little spring resistance.

    Jeff Turner

    When I had my forks apart, I put progressive springs in. This made the caps more difficult to get on. I did the following:

    • Clamp fork slider in soft-jaw vice

    • Hold cap with crescent wrench then put my palm on the cap/wrench combo to hold it square to fork tube

    • Turn fork tube with other hand while putting pressure on cap

    • Get a good 2-3 turns after thread engagement before letting go with wrench hand

    • Finish tightening with wrench

    After doing this several times (more than I wanted to actually), I found this to be the easiest method. It's also a better way to prevent cross-threading.

    Curt Marsh

    I use a similar method to Rick's. I have air caps on both my XS11, and not being a "big, burly guy" like Rick, I use a wrench. I start it like he does, but before I release it I use the wrench to get a extra turn. That way it is securely caught in the threads.

    Michael Hart

    Different models have different top cap configurations, some are more or less easier to deal with than others. I have found that turning CCW a bit first to get the threads aligned reduces chances of cross-threading, and makes chances of biting in right on the first turn a lot better. I can actually use a socket on the XJ; the 79F has a HUGE nut size on top, I used a very large crescent wrench; the 79SF I used a regular size crescent. My biggest worry each time is the dreaded crossthread. Not sure if my turning it CCW a bit really helps or not, but I haven't yet crossthreaded a cap (knock on wood).

    Tim Sears

    I had this same problem when I changed my fork oil. I had to do all of the above AND instead of holding the cap in my hand, I clamped on it with some vise-grips (protect the metal w/ some cloth!). When it went on without stripping, I immediately faced east and kissed the ground!

    James Haralson

    • Put the bike on the center stand, someone on rear of seat, or jack under front of engine. This gets weight off forks.

    • Turn cap counter clock wise until it clicks. That will show you the start of threads.

    • Gently screw them in.

    Johnny Yukon

    There is certainly some pressure there! When you're ready for capping, be sure to start 1/4 turn or more wrist action before where you think the screw action begins.... with an even leverage.

    You will feel proper connectivity.... If you don't... do it again!!!!!!
    Last edited by tplank; 11-09-2020, 11:08 PM.