Fork seals

[geraldlanc]

After just 7k miles, my left fork is weeping oil. The right is not. Should I replace the seals in just one or do both? Does anyone have the seal driver tool for sale?

Gerald

[pwhoever]

When was the last time the right seal was replaced? If it's been a while, IMHO, I would consider doing both. If it's been 7k miles since both done, I would only do the left. One of the most common reasons that there is failure on left fork seals is that the anti dive valve has failed in the activated position and this causes too much pressure in that fork, and then it ends up leaking. What I did was add a shim so that even if I have a problem, it has no effect on the fork. In my case, I have Progressive Suspension fork springs so the ADV isn't even necessary. But I've been told that on trikes, the ADV valve isn't really necessary anyway, it's more important on the 2 wheeled GL1800's. Also check the upper tube really good to make sure that there are no nicks or excess dirt that can tear at the seal causing a leak.

[pwhoever]

One other thing, it might be worth tryil the sealmate tool which could get any dirt or debris cleaned out and might solve the leak. At least temporarily and cheaper and easier to do. There have been some that made a DIY version from a plastic soda bottle or some old 35mm negatives...

https://sealmate.net

[geraldlanc]

When was the last time the right seal was replaced? If it's been a while, IMHO, I would consider doing both. If it's been 7k miles since both done, I would only do the left. One of the most common reasons that there is failure on left fork seals is that the anti dive valve has failed in the activated position and this causes too much pressure in that fork, and then it ends up leaking. What I did was add a shim so that even if I have a problem, it has no effect on the fork. In my case, I have Progressive Suspension fork springs so the ADV isn't even necessary. But I've been told that on trikes, the ADV valve isn't really necessary anyway, it's more important on the 2 wheeled GL1800's. Also check the upper tube really good to make sure that there are no nicks or excess dirt that can tear at the seal causing a leak.

They were both rebuilt 7k miles ago. I previously deleted the ADV with a shim and I have a seal mate which I used, but it is too cold to ride now to see if that helped.

Gerald