Fork Seal Replacement

Started by Herman, March 15, 2008, 10:54:48 PM

Previous topic - Next topic

Herman

I just noticed some fork oil leaking.  I went to the tips and tricks section on the MOOT web page, but nothing pops up when I click on the links for fork seal replacement.  Any one know where I can get some detailed info before I take on the task.

Also, what parts should I replace while I'm digging in the forks?

dan twomey

It can be found on the MRA web site.  Here's the link:

http://www.magnariders.com/html/TipTrick/dust_seals.html

If you haven't already, this would be an great opportunity to install a set of progressive springs.  I used a heavier weight oil when I reinstalled everything too.

Greg Cothern

Put the bike on a lift and make sure its secure.
Remove the front wheel place a drain pan to catch fluid.  Check for golden flecks, if you see quite a bit think about replacing the brass bushing's as well.
Drain the fluid (94's and early 95s had a drain plug visible on the lower outside of the fork) later have a allen head bolt up through the bottom of the fork, accessible once the axle has been removed.  TAKE great care not to strip this as it is easily stripped.
Loosen top triple tube clamps a bit, a great time to replace stock soft springs for some good Progressive units, I believe this to be one of the top mods on the 3rd gen Magna.
Removed the dust seal with a small flat blade screwdriver, or pocket knife etc being careful not to damage the fork tube.
Remove the seal clip.
Gently slide lower fork legs up a bit, then quickly and a bit forceably slide all the way down to force the seal out. 
Remove components taking note of order they are in, they have to go back in proper sequence.
Take note of orientation of the factory seal so you can put the new seal in proper side up.
Clean all parts making sure there is no signs of burrs, rust, or imperfections on the fork tubes them selves.
Pick up some 2" PVC, cut it so you have two clam shell halves, you will use this to drive the seal back into it position in the lower for legs.  I have found it works well to clamp the 2 piece's of PVC with your hand and work it as a slide hammer.  It will take some force to push them back home.
Reinstall seal clip.
Reinstall dust seal.
If going with Progressive springs, simply slide the new springs in up top followed by the stock washer, NEW PVC spacer cut to 5.12" length.
Reinstall drain plug.
Fill with 532 ml's of your choice of fork oil per fork tube (stock oil weight is 10wt, 15wt is consider by some a better weight).
With a helper, take a long extension on your socket and thread the cap back into place by hand (I have found it works best to place the palm of one hand on top of the extension to hold the down force while turning with the other hand) once you are sure you have not cross-threaded the cap (it is very easy to strip) then you can tighten to specs.
Reinstall front wheel and axle.
MAKE sure you work the front brake lever several times to make sure you have the front brake pads back to the rotor.
Greg Cothern
00 Valkyrie Interstate
96 Magna 
Previously owned:
87 Super
96 Magna project bike
95 Magna "Pay it forward"