BMW motorcycle telescopic fork alignment procedure, Randy Glass, page 12

12 – Assembly

      Once the tubes are in alignment it is time to start putting things back together.  The first step is to reassemble the top plate.  This is critical.  It is important that this fits nearly perfectly.  With the fork springs removed it is important that, with the upper spring retainers removed, and with the steering bearings correctly adjusted and the top retaining nut tightened, that there be something close to zero clearance and zero interference between the upper fork bracket and the tops of the fork tubes, within reason, regardless of the 160mm (6.3″) amount of fork tube that the factory states should protrude above the yoke boss.  This to keep the upper fork bracket from being too badly deformed and from stressing the fork tubes when the two spring retaining nuts are torqued.  You should be able to replace the top plate, hand tighten the steering bearing lock nut, then hand tighten the two spring retainer bolts all the way leaving zero clearance between the tops of the fork tubes and the bottom of the upper fork bracket.  The exception to this is that the interference fit between the upper fork bracket and the upper spring retainers is close and may require a light force with a tool to fully seat them.  This is particularly true if you paint the upper fork bracket.  If this assembly does not fit properly, torquing the three nuts down will put pressure against the fork tubes and will ruin all your hard work.

      I had some apprehensions about how well the legs would go together and work, mainly due to the factory fork brace (which on the /7’s is a one-piece, stamped stainless steel part that also doubles as a fender mount).  From what I have seen, these were made to fairly low tolerances.  I started the assembly of the legs this way (blue numbers below refer to the image):

tightening procedure for fork legs

After I installed the new fork seals and after the three large nuts were tightened on the upper fork bracket, I

(1) slid the two fork legs onto the fork tubes and installed the two nuts on the bottom of the dampers to hold the legs in place.  I left off the sealing washers for this part.

(2) I then slid the axle through the fork legs and after pushing the assembly up the fork tubes as far as was possible…

(3) I slowly tightened the pinch bolts.  While I was tightening the pinch bolts I was also twisting the axle slightly so that I could get both pinch bolts tight at the same time, thus allowing the legs to self-align during this part of the process.  This also shows that the axle is not bent.  I pushed the axle just a little further then normal out of the “nut end” (4) so as to be sure that the pinch area was getting a good grip.

(5) When the pinch bolts were tight I held the axle with one hand and slid the fork leg assembly up and down the tubes to assure myself that they were moving freely.  They were sliding beautifully at this point. Better than they had in a very long time.

(6) I have a Telefix fork brace.  With the axle now tightened and the legs all the way up on the tubes (the fork springs were still on the work bench) I installed the Telefix.  I took pains to be sure that the brace would hold the tops of the tubes in their present position without any inward or outwards pressure. When the brace was tightened I slid the entire fork leg assembly up and down the tubes to assure myself that the installation of the Telefix had not changed the previous adjustments.  What I had created at this point with the fork legs was a relatively rigid assembly.  I was assured that the two legs were parallel because they were sliding on the fork tubes that I had adjusted to parallel.

Now I inserted the fender and its brace between the legs.  Even thought I had adjusted the brace years ago, I could see that, without the Telefix fork brace in place, the stock fender mount would indeed put a bit of outward pressure on the fork legs in the front and there was a slight gap at the rear.  If I used only the stock fork brace it would put stress on the upper end of the fork legs causing a mis-alignment.  So what I was doing here was using the Telefix brace as a jig to hold the legs in place, and I then used the legs as a “width gauge” to check the fit of the factory fender brace.  With my set-up, once the assembly was complete, most of the stress would be on the fender brace itself and not on the fork legs because the Telefix would hold things in place against the forces created by the fender brace.

If you do not have the Telefix I suggest that you remove the fender from the factory brace and test fit the brace between the fork legs on its own.  It should slide between the fork legs with no outward pressure against them once installed (with the same sort of feel you get with a feeler gauge when you adjust your valves- think of the brace as the feeler gauge and the fork legs as the valve stem and the rocker).  You are looking for a “loose .000″ fit.

If the stock brace is too wide you can try to use a really large vise to move the mounting ears together a bit. Try to clamp at the bend and not out at the ends of the mounting ears.  PLEASE BE CAREFUL!  The brace acts like a big spring and if it slips when it is compressed in the vise it can go flying!  A length of rope or cable through one of the mounting holes and tied to the vise as a safety device would be wise here.  Shim washers can be used to deal with a brace that is too narrow.  The closer the fit to .000” clearance and zero outwards force, the better.

When you think you have it adjusted properly, mount it back to the forklegs with the proper hardware.  Check your work by manually sliding the entire assembly up and down on the fork tubes again to assure yourself that you have indeed accomplished something here!  It should feel good.  Really good! About all I could feel here was the friction of the fork seals against the tubes.

      Once you have all of this assembled, slide the fork leg assembly off the tubes and place it off to the side where it won’t get knocked over and tweaked out of alignment.

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