Adding fork oil

I just fixed a fork seal leak (used a business card; thanks to all who gave me the advice). Now I need to add fork oil since I lost most of it before I could stop the leak. Can someone give me some help on how to do this? Do I just remove the fork cap on both and add the oil, or is it more complex than that? Thanks in advance for any advice.

The manual says to be so many inches from the top. I have done this several times on my WR426, but forgot what it was. Someone in here may remember. I think it was 5" or so from the top when the fork was totally compressed (spring out and bottomed out), I dont know what it would translate into with the fork on the bike. One option is to measure the side that didnt leak and match it? :cry:

You should completely drain both forks. You will want the same viscosity of oil in both forks and want the oil level to be the same in both forks. Viscosity and oil level will effect the the ride. Heavier oil = harsher ride, higher oil level = harsher ride.

The manual for my 98 WR400 has the standard oil level at 145mm (5.71 in)

Extent of adjustment:

80~150mm (3.15~5.91 in) from top of outer tube with inner tube and damper rod fully compressed without spring.


Be sure to install spring guide when checking oil level.

If you need more info I could scan the pages and send them to you, let me know.

[. One option is to measure the side that didnt leak and match it? :cry:

Definately. You may as well change the oil in both, and match them. Also, the more oil/less air will increase bottoming resistance. If you take big air on jumps, you'll notice this. If you are into trail riding, you'll be better off with a lower oil level. :cry:

If you want to just top up your fork yes, you just open up the cap and fill to the required level int the manual. More oil for more bottoming resistance.

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