Motorcycle Fork Seal Rebuild Part 2 (of 2) Cartridge Type

How to replace the fork seals on a motocross bike. This is Part 2 of our 2 Part video which covers the assembly of the fork. Part 1 covers the disassembly of the fork and parts inspection. This instructional video covers the rebuild of the Cartridge type fork which is commonly seen on late model dirt bikes. Replacing your leaking fork seals is easy and we’ll show you how to do it! Get all the parts and tools you need @!

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Title : Motorcycle Fork Seal Rebuild Part 2 (of 2) Cartridge Type
Video Length : “07:38
Channel | User | Playlist : Rocky Mountain ATV MC
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RockyMountain MC

RockyMountain MC

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  • Nope on the cartridge type forks you don’t need to do anything with the bottom of the inner fork leg. Only on the dual cartridge forks would you remove that assembly

  • That’s pretty standard as far as shop rates go but they can range. You could pay anywhere from $100 all they way up to a couple hundred for someone to rebuild your forks. In other words you are probably looking at an hour and a half to two hours for a rebuild

  • hi I have a 2001 yz80 2stroke and I bought new fork seals and duster’s because they were leaking, I was going to take the forks off they bike and bring them to Yamaha and see if they put them on and fill them up with oil.. About how much do you think it would cost?

    • The service manual says the standard oil level is 110mm but the adjustable range is 105-140mm of air space with it fully compressed and the spring removed. You’ll need a fork oil level tool to measure the fluid level correctly if you don’t already have one. Let me know if you have any other questions

    • When fork seals get torn or start to wear out they can leak which reduces the amount of oil in the fork. This can cause the suspension to blow through it’s stroke and doesn’t allow it to work how it was designed. If you leave it like this for long enough it can wear out other parts in the fork such as bushings and collars along with other parts making it more and more expensive to fix.

    • +Rocky Mountain ATV MC thank you for the quick respond. so meaning I just have to wait for the Fork Seals to get torn or starting to wear out. Coz I thought like the engine you need to change the oil for every X mileage

    • +Stephen Perez
       This is also true. Most manuals will recommend replacing the fork oil every 5 or so rides or around 15 hours for competition use. Over time oil will break down and loose its lubricity so it’s good to keep the oil fresh to help prolong the life of the inner fork components. Fork seals have no life expectancy or guarantee as to how long they will last so changing your fork oil on a regular basis is always a good idea to keep your forks feeling and functioning the way you want them to.

  • Hi from Costa Rica your videos are great!!!, i have a problem my bike has an oil leak near the retainers, i changed it but again i again i have the problem, the bar is perfect not scratches i check it a lot. So the bar is good, retainers are new and it continues leaking from the retainers, any suggestion?  my bike is normal suspension like this in the video. Regards,

    • Which bike are these forks on? So you’ve installed new oil seals and it continues to leak? I would first inspect your seals and look for any small tears for missing pieces. How long after you installed new seals did it start leaking again? The life of a fork seal really depends on the type of terrain you ride in and how clean they stay. If dirt or sand gets up in there the seal can leak almost instantly. I would also inspect both the inner and outer retainer and make sure the teflon coating is good on both of them. If not replace those and see if that fixes your leak.

    • Yes, that’s just fine. That is what you are doing when you lift the dampening rod up and then down through it’s stroke is you are filling that assembly with oil. You want to purge all the air from that cartridge for the fork to function properly. So yes, it would be just fine if you poured oil into there as you were adding oil to the fork.

  • If you use the seal bullet on dis-assembly,…and re-assembly,…you can reuse the seal. They almost never “wear out”. But,..they do get dirt built up inside and leak. Clean it well in the tank and sink with soap. Inspect carefully. OEM seals lasts forever.

  • Nice vid.. but one thing is kind of missing.

    That is, it isn’t same for all parts if you put them together upside down or in reverse, so it’s better to keep track of orientation while disassemble, like always have upside parts pointing to same side where you lay them etc.

    • +federico moroni That should not matter. As long as you put both springs the same way you’re fine. I haven’t heard of any fork spring going a certain direction before. In theory, where you have tighter coils in the spring that side should go up being that it is heavier.

    • +Rocky Mountain ATV MC tank you very much. last time with my suzuky showa i made many mistakes and i lost oilseals during a race :O
      now i retryed with my cr 124 kyb and everything was right with your help.
      tank u

  • спасибо! У Вас очень хороший канал! Интересный и полезный! Хоть и слов не понимаю 🙂

  • my owner manual suggest 15-10 fork oil. but which one though. whats the differences between these two. i ride 07 zx10r so i need more thicker oil like 10

    • +Kawaii Ninja I would check your service manual again.. it should recommend what specific weight of fork oil you should be running? If not, i would check with your local dealer to see what they are putting in them for that same model bike.

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