The member photo gallery is now integrated and live!!  All user albums and pictures have been ported from old gallery.

To register send an e-mail to and provide your location and desired user name.

Author Topic: Fork Seal Lessons  (Read 188 times)

Offline montmil

  • Posts: 8371
Fork Seal Lessons
« on: April 30, 2008, 08:24:40 PM »
My 1981 R65 now has fresh fork seals and a full cleaning inside the legs and sliders. There was nothing overly difficult about the job but I did add a few new skills to my bag.

Prior to beginning the work, I took advantage of the "Disorganized R65 Forum" and asked for tips from thems that been there. Thanks to all who offered their experience and knowledge. [smiley=thumbup.gif]

Here's a few thoughts regarding the fork seal job... in no particular order as this is the official and "disorganized" forum:

1. I now believe it's best to remove the circlips, top caps and fork springs prior to attacking the Allen screws in the bottom of the sliders. As mentioned, I was probably lucky that the lower screws came out without a hassle. Still had to strip the tops in order to torque the lower Allen screws at final assembly.

2. The circlips confounded me at first until I discovered that they are not positioned in an actual machined groove but have the lower groove shoulder tapered downward into the fork stanchion. After this light bulb came on, it was simple to push them down with a small flat-blade screwdriver, turn them to a sorta vertical position and lift them out with needle-nosed pliers.

3. Expect to find some "mud" on the damper rod seat and inside the bottom area of the fork slider. I was concerned until a member said this was kinda normal if you don't disassemble the legs every 15 years or so; even if you do change fork oil annually.

4. I used a small smear of grease to retain the mushroom-shaped damper rod seat to the damper rod as the lower slider was reinstalled onto the stanchion. After cleaning off the biohazard crud, the seats wanted to slip right off.

5. Check the condition of the rubber O-rings in the aluminum stanchion caps. Easy replacement at this stage of the job. Try your local Ace hardware store for O-rings. I've found several "BMW" O-rings and grommets that are just the right size. Good prices, too.

6. Manual states that the relaxed length of the fork springs should be between 19.25" and 19.75". OK, the manual sez it with three decimal points after nineteen but, jeez... Both of mine taped at 19.50" so I'm happy. Middle of the road and good to go. Just sorry I didn't find some nice progressive wound goodies. Mine look to be stockers. They have a red-ish paint swatch on each spring. ?

7. Now, if I can just get the outside of those lower sliders cleaned up...

Monte Miller
Denton, TEXAS
1978 BMW R100S
1981 BMW R65
1983 BMW R65
1995 Triumph Trophy
1986 VW Cabriolet