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Discussion Starter #1
I recently made a total reassembly of the fork on my wife's VN750 -86.
The reason was leaking seals.
Soo i changed the seals and the oil and assembled everything again.
Problem is, the fork still leaks oil..:BLAM:
I checked the forks for scraches but couldnt find any bad.
What can be wrong???
Please help me..

/Tony
Sweden
 

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and the Adventure Cycle
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When ya say "Couldn't find any bad" does that mean ya did see some light scratches?
Even slight ones could still cause them to leak, as well as a possibly an out of roundness (from a dent, be it ever so slight).

First thing I'd suggest is to get something like a piece of 35mm film negative and slide it between the fork and the seal, then carefully work it around the fork.
This will help get any pieces of grit that may have got under the seal out.
 

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Discussion Starter #3
Thanks for the reply!
I will test the film trick and see if it helps.
There are some light scratches but no dents as far as I can see.
 

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Question about the camera film thing...

Do you have to remove anything first, or just try to slip it down into the fork? I'm new to bikes, so maybe its a dumb question. There is a black plastic thing on top of the fork where the oil is leaking out. Do I have to loosen that first, or is that part of the seal?

I wonder if I sprayed something in there, like brake cleaner - might it clean it out too or would that damage something?
 

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Search Goddess
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I would think if you spray brake cleaner around a leaking fork seal you've pretty much contaminated the fork oil.
 

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and the Adventure Cycle
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Yeah, like Dianna said, DON'T spray anything around it.

You shouldn't have to remove anything to do the film thing.
Just work it carefully in between the dust cover/seal and the fork tube.
 

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"Just work it carefully in between the dust cover/seal and the fork tube."

Correct me if I'm wrong here.......but this statement tends to indicate that the fork seal and dust cover are one in the same. They are not. I've seen this "film strip" suggestion in here previously, but now, having replaced my seals and thinking about this for a moment, it's not making sense. The "black plastic thing" that Spaceboy refers to is the dust cover and a piece of film would probably slip between it and the fork tube. But the seal is whats leaking the fork oil and that's below the dust cover and sort of held in place by a circlip type retainer and that sits in a channel. I'm not sure that the film strip would slip between the seal and the fork tube even if it could pass the circlip since my was tapped in using a hammer and a piece of PVC as demonstrated in Bulldogs pictorial.

Am I not understanding something with this filmstrip thing?
 

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and the Adventure Cycle
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Sorry, I didn't mean for it to sound like the 'dust cover/seal' were one in the same part :doh:
Guess I shoulda said 'dust cover and the seal'

I haven't really tried this on the Vulcan, but have on my dirtbikes.
So, are you saying it's not possible to get the filmstrip between the two? (I actually used a piece if .015" or .020" shim stock on the dirtbikes, but most people have easier access to film negatives)

Maybe I'll give this a try on my bike, seeing as since it's been sitting a little while, there are some signs of oil there.
 

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You can do the "film strip" trick, but yes, you first have to pry up the dust seal and push it up out of the way.
There is no guarenty that this will fix your leak however. Am assuming here you did not put too much oil in the fork, and that you did in fact install the proper seals. (parts departments have screwed up before you know...)

Get a fairly strong magnifiing glass and examine the fork tube carefully. A small scratch can leak oil, dents may be harder to see, but are worse. If it just one leg that is leaking , take it off the bike to examine if need be.
You can remove the spring and replace the fork plug so you can pump the the fork up and down by hand...clean off the tube and pump it a few times being carefull not to twist the tube. Use a thin sheet of rice paper or something as thin to see if you can locate where the oil is leaking from. It may be a dimple on the tube, or it is just a faulty seal.
Dinged tubes can not be "sanded" smooth, you will have to replace it.
If the tube just looks fine to you, try installing another seal ...


KM
 

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Discussion Starter #10
Thanks for your tips!
It almost seems to me as the seals are faulty in some way.
Both fork legs are leaking.
After replacing the seals, I added the oil amount stated in the clymer manual for a US bike(Although I'm in Sweden, the bike was originally built for the US market).
The bike also has the possibillity to add extra airpressure to the forks, I did add some with my handpump. Could that have damaged the seals?
If I added to much oil, could that damage the seals also or will the excess oil leak out and everything is fine?
I'm a little unsure if the seals were installed with the right side up, could this cause leakage?

/Tony
 

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Thanks for your tips!
....I'm a little unsure if the seals were installed with the right side up, could this cause leakage?
/Tony

Uh, yeah. If the seal was put in upside -down, it would leak like the Titanic after it hit the iceburg...Adding air would only compond this.
You might want to take the forks off and take them to a shop and have them do the work..if they still leak , the shop will be responsible.....

KM
 

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Discussion Starter #12
:BLAM:
The more I think of it, something tells me I have put them upside down..
Otherwise, I find it quite impossible for both seals to leak in the exact same way.
I have uploaded two photos of one of my old seals from both sides on
photos.yahoo.com/anfrewo album "vn750".
Could someone please tell me which of the pictures is "up" and which is "down" so I am able to assemble it correct this time:doh:

Is there any risk that my new seals have been destroyed by putting them upside down? Or would it be possible to "just" reassemble the forks and put the seals back but correctly this time?
 

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Discussion Starter #13
Just tried the film trick.. no chance of getting the film between the seal and the fork leg...
I checked the seals and they are both with the most open grove upwards.
Is this right or wrong?
If someone could post a picture of their assembled fork seal it would be of great help!

/Tony
 

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Growling at the World...
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Another thing to look at is were the seals aftermarket or Kaw? I've been told by more then one shop, both Kaw and general shops that the aftermarket fork seals for the Vulcans are pretty crappy and that they all use the OEM Kaw seals. I've been bitten once by aftermarket fork seals and have used Kaw seals every since...
 

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Discussion Starter #15
The seals are aftermarket yes..
Bought them at a kaw dealer:doh:
I will contact them and order a couple of new OEM seals..
 

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Did anyone take pictures of the seal in the correct orientation? I'm replacing the seals on my bike and I'm confused by the note on the Clymer's manual. It says the open groove facing upward but the seal has grooves on both sides and just by looking at the seals it seems to me like the "most open" side should be facinf down. I had a shop replace the seals a couple of years ago and they did no install them with the "most open" side facing up and they are leaking. I thought they were upside down but now I don't know. Please help!
 

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