Syringe Fork Oil from the bottom up...?


Information and questions on GL1200 Goldwings (1984-1987)
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Psycheonabike
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Syringe Fork Oil from the bottom up...?

Post by Psycheonabike »



Is this possible? Would avoid struggling getting spring back in etc...?


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Viking
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Re: Syringe Fork Oil from the bottom up...?

Post by Viking »

I guess you could, as long as you could plug the hole while you add the oil, and also have a way for the air to exit so the pressure does not push whatever you are plugging the bottom hole with out of the fork. I would think a better method might be to drill and tap the top caps and put plugs in them. Then you could drain the oil out the bottom, put the bottom plugs in, and then fill from the top with the syringe.
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Psycheonabike
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Re: Syringe Fork Oil from the bottom up...?

Post by Psycheonabike »

Now that sounds like a good idea!

Is getting the caps back in really that difficult a job?
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Re: Syringe Fork Oil from the bottom up...?

Post by Viking »

It never has been for me. Just need to be able to put the pressure and turn the cap taking care not to cross thread. I have replaced springs with Progressives and still had no problem putting the caps back on. Allowing the forks to fully extend by lifting the bike helps, but is not essential. I have done it on center stand only.
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Re: Syringe Fork Oil from the bottom up...?

Post by geraldm »

If your going to put plugs in the top . When you are finished adding the correct amount of fork , make a dipstick , mark on it the full line ,. Then you can check to make sure oil is full , works great . Then if you suspect a bit of a leak you can check to see if its full .
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Re: Syringe Fork Oil from the bottom up...?

Post by Psycheonabike »

Anyone know of a walkthrough for adding plugs?
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Re: Syringe Fork Oil from the bottom up...?

Post by Viking »

Obtain two fine thread small bolts
Remove caps from forks
Center punch the caps.
Drill right sized hole using a drill press
Tap the holes with the correct fine thread tap
Clean burrs from edges of holes
find O-rings and washers to ensure holes are sealed

Assemble washers and O-Rings onto bolts in that order and install in threaded holes.

Replace caps on forks

You are done.
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Re: Syringe Fork Oil from the bottom up...?

Post by geraldm »

If you drill the plugs maybe tap them to npt.( National pipe thread. ) of the size you want . Then it is not necessary for any O rings and seals. Its very easy to do , if you think your going to have problems . Make a couple trial holes in a piece of iron and do a few until you feel confident with everything.
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Re: Syringe Fork Oil from the bottom up...?

Post by WingAdmin »

Or just tap the caps to accept a schraeder valve. That way you could adjust air preload easily.

Just make sure you remove the caps before drilling, you don't want metal bits falling down inside your forks - that would do catastrophic damage to the forks and seals!

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