Greasing fork dust seals

[Audi403]

Hey guys,

 

I have a seeping fork seal. The leak isn't too bad but you can see the top of the dust seal becomes wet with oil after a ride. I'm going to use a Seal Mate to try and clean the fork seal. While I have the dust seal popped off I also cleaned all the crud from the inside of it. I noticed it was greased so I checked the service manual and BMW states to lightly grease the sealing boot (aka dust seal) with Unirex N3. I looked up this grease and it is an NLGI #3 barium wheel bearing grease. I have an assortment of grease (Staburags NBU 30 PTM, Castrol Molub Alloy Paste TA, Lucas Red N Tacky, and Belray Waterproof) but none of these seem to be NLGI #3. I guess NLGI #3 will have a thicker consistency than a #2. 

 

I'll likely just run to the store and grab a tube of any NLGI #3 wheel bearing grease. I'm assuming it doesn't necessarily need to be barium based? I'm also assuming the grease it to be applied to the inside diameter of the dust seal where it sits on the fork tube to help prevent dust from getting through to the fork seal? Maybe also around the bottom where it pops into the fork? It would be a lot easier to grease this with it off the bike. My thought was to apply the grease on the fork itself, then spin the seal in it to apply it onto the seal, pop it down into place, then clean the remaining grease off the fork. Thoughts?

 

 

[wbw6cos]

What year/model bike are you having issues with?

 

You may want to post it under Oilhead, Hexhead, or Camhead, depending on year model.   That way it will get noticed more for specific bike tech help.

 

End of P.S.A.

[Audi403]

This is a generic question about greasing sealing boots (dust caps) for forks. It should apply to most models. I have a Shiftcam but it's sort of irrelevant. 

End of PSA

[Audi403]

It looks like NLGI 3 wheel bearing grease is not readily available. I went to three stores and all their grease was NLGI 2. Maybe I'll just use an NLGI 2 lithium wheel bearing grease.

[TEWKS]

Another PSA here. 

I think when you ask a question seeking help and somebody responds with sound advice on where to get the info requested, a snappy answer isn’t going to promote more help. 
 

End of PSA. 

[Audi403]

It is not a snappy answer, just simply stating the facts. It is a generic, non model specific question. Answering in a condescending fasion doesn't promote healthy conversations. This isn't how people talk to each other face to face so why are we acting like this on our keyboards.

End of PSA

[TEWKS]

I’m pretty sure if you were hanging out with a group of Harley riders and you had a problem with your BMW, somebody might suggest going to a BMW shop. “To get you closer to a solution”  I think that same sort of thing happened, somebody was trying to direct you to the quickest help. And if it wasn’t a snappy answer, sorry, maybe I’m just feeling a little over sensitive these days. 

[Audi403]

For anyone actually interested in the topic I've posted about, here's what I did. I popped the dust caps off and thoroughly cleaned both the dust cap and above the fork seal. I covered above the fork seal to prevent debris from falling in. I then ran the Seal Mate around the inside of the dust caps which cleaned a lot of grease and dirt out. I then cleaned around the fork seal again before using the Seal Mate. I ran the seal mate around once, removed it, and wiped all the gunk off (it did pull stuff out). Then I did the procedure one more time. You're going to want to wrap a cloth around your fork as oil will seep out while you do this. I then pumped the front suspension and wiped the oil off the forks to reseat the seal. I did this 5 or 6 times and each time it appeared the stanchion tube was less oily.

 

As for my question about greasing the dust seals, this is what I did. Applied a lithium based high temp wheel bearing grease to the upper fork and spun the dust seal around in it to grease the inner diameter. I then lightly applied the grease around the perimeter of the dust cap and popped it back on the fork. I cleaned the extra grease off the stanchion tube after.  Did a 100km test ride and it appears to have fixed the leak. Hope this helps someone. 

[Audi403]

27 minutes ago, TEWKS said:

I’m pretty sure if you were hanging out with a group of Harley riders and you had a problem with your BMW, somebody might suggest going to a BMW shop. “To get you closer to a solution”  I think that same sort of thing happened, somebody was trying to direct you to the quickest help. And if it wasn’t a snappy answer, sorry, maybe I’m just feeling a little over sensitive these days. 

Is this a Harley Davidson forum, or a BMW forum? Again, this isn't a model specific question so I didnt post it in a model specific section which would limit the audience. This applies to almost all motorcycles. I should have posted it in the Harley forum, I probably would have received more help.

[Hosstage]

Us Harley guys are a friendly bunch, you can even ask which oil is the best!

 

And thank you for the write up on your solution.

[Audi403]

6 minutes ago, Hosstage said:

Us Harley guys are a friendly bunch, you can even ask which oil is the best!

 

And thank you for the write up on your solution.

Haha. I have more than a few friends with Harleys. I used to ride a Victory Highball. The Harley community is great 👍 

[dirtrider]

1 hour ago, Audi403 said:

Is this a Harley Davidson forum, or a BMW forum? Again, this isn't a model specific question so I didnt post it in a model specific section which would limit the audience. This applies to almost all motorcycles. I should have posted it in the Harley forum, I probably would have received more help.

Afternoon  Audi403

 

But it is actually model specific as until the recent BMW motorcycles the BMW service manual made no reference to using grease on or under the dust excluder seal. 

 

 

 

 

[Audi403]

28 minutes ago, dirtrider said:

Afternoon  Audi403

 

But it is actually model specific as until the recent BMW motorcycles the BMW service manual made no reference to using grease on or under the dust excluder seal. 

 

 

 

 

Interesting. I found this information in the K52 service manual so they've been doing it on the RT's since at least 2014. I also found a video of Dave Moss doing it. It's a pretty common practice.