'83 XJ900 Fork seals

Now that I have the bike running, time to address some of the other issues. When I pulled the front wheel to mount a new tire, I noticed the fork seals are leaking. Quite a bit in fact. The pads are soaked. Guess I need to deal with that.

I went looking for seal kits, but it seems you can only get oil seals and not dust seals. Even in Len's pages, I don't see dust seals listed for the 900. Does it not have separate dust seals? It looks like it does.

While we're on the subject, any words of wisdom on replacing seals on the 900? I've done lots of fork seals, including my Seca 750, so I know the general process. Just wondering if there is anything unusual about these I should know about or if they are pretty typical.

 

Just go to a major Yamaha dealers website selling parts.
Pull up the schematic of your forks
This will tell you if there is anything truly unique about the dust seal
Did you find All-Balls kit for it?
They usually come with dust seals

 

Sometimes you can click on the part and see what other bikes share it.
I personally don’t know much about the 900 forks, I think they are 37 mm same as the 700 Maxim so same oil seals anyway

 

Here they is:

LOWER (OUTER) FORK TUBE PARTS:

Dust Wiper Seals:

HCP1822 OEM lower fork tube DUST WIPER SEAL, fits either left or right tube on the following models: 1984 XJ750RL Seca (44X Canadian models) and all XJ900RK, RL, F, N, and FN models. One seal does one tube. Each:
$

HCP21561 Aftermarket lower fork tube DUST WIPER SEAL, fits either left or right tube on the following models: 1984 XJ750RL Seca (44X Canadian models) and all XJ900RK, RL, F, N, and FN models. One seal does one tube. Each:
$


The aftermarket seals are exact reproductions of the originals.

The dis-assembly of the fork tubes requires that the inner tube be pulled out of the lower tube with a significant amount of force, as the bottom of the inner (chrome) tube has an "expanding" (spring steel) slide bushing at the very bottom, and this "expanding" bushing has to be man-handled to get it past the lower tube bushing....which is located just below the oil seal in the lower tube.....in many case the upper bushing will actually pull the lower tube bushing out with it, which is actually a good thing if you plan to replace that lower bushing (otherwise, the lower bushing is kind of a bear to extract by itself).

The anti-dive units may need to be rebuilt, and certainly will need to be cleaned thoroughly as brake fluid sludge and fork oil sludge can render them ineffective:

https://www.xjbikes.com/forums/threads/xj900rk-anti-dive-stripdown-how-to-with-pics.44997

 

Couldn't find an All Balls kit that had both. Just some cheap Chinese kits with questionable fitment lists. I did finally find a set of "Leak Proof" brand on Partzilla though. Weird how few listings there are for full sets.

Len, thanks for the info. Not sure why I didn't see those on your page. I saw some dust seals but didn't see the 900 listed. Must have been looking at the wrong ones.

Can't wait to see what awaits in there...I remember when I did the 750...some of the nastiest foul-smelling goo I've ever seen came oozing out.

 

Yes, as part of the non-maintenance that most people (don't) perform, changing the fork oil (and final drive oil.....oh, and brake fluid too) is at the top of their lists.

Luckily, changing engine oil (and maybe even the filter!) is something that most previous-owners seemed to be aware of, and attended to on a bi-decade schedule.

 

Got the forks removed and drained. I'm going to venture a guess this will be its first fluid change ever. Didn't smell quite as nasty as the 750, but a pretty thick goo nonetheless. The side that was leaking the most looked like it had maybe half the fluid of the other. Obviously been leaking for quite a while.

Hardest part was getting those air fittings off. They were kinda stuck and it took quite a bit of effort to get them to move. Finally had to resort to some channel locks and an old inner tube along with some silicone spray to get them to break free. Once the silicone got down to the orings they slipped off fine.

Need to collect some parts before I go any further.