How to adjust stock 89/90 (maybe 91-93) forks ? No owners manual

[capitanoinsano]

And I forgot to mention ....

DDDUUUUHHH!!!!

Thanks for the help guys, maybe someone who is equally confused will find this thread in the future.  Bottom line is fork tube must sit in bike so that middle hashmark is pointing forward when looking at it while sitting on the bike.
At least that is if others agree?

[Shaun]

Now your getting it, sounds like you've got it figured out.

[SlowOldGuy]

Bottom line is fork tube must sit in bike so that middle hashmark is pointing forward when looking at it while sitting on the bike.
At least that is if others agree?

I don't think that's quite right, but you're kind of on the correct path.

The marks of my fork caps are arranged with the thinnest mark at the 12 o'clock position.  The is strictly a function of the rotational position of the damper rod.  With the DR in the correct position, once you drop the fork cap in the tube, as you screw the cap in, the DR adjuster rod will "float" in the cap.  When the threads bottom out, the red dot on the DR adjuster will line up with the appropriate mark.  If the damping location was the first position when the DR was installed, the the dot will line up with the thinnest line when the cap is tight. 

If the rotational position of the damper rod is not correct, the red dot on the DR adjuster will end up at a random position.  Or, in your case, it sounds like the DR is 180 degrees out; therefore, the red dot will always be 180 degrees from a cap mark.  You should be able to loosen the triple clamps and rotate the fork tube 180 degrees to bring the adjuster into agreement with the cap marks. 

DavidR.

[RichBaker]

Thanks for the help.  I can use an M12 Allen tool to adjust preload, have done that.  But the damping adjustment still has me confused.  On the left fork I can line up the red dot on the flat blade screwdriver damping adjuster so that the dot reaches a detent on each of the 3 settings.  But on the right fork the detents for the damping adjustment do not line up with the detents.  So I checked a spare set of forks and found the right fork on that set was the same way.  Does the right fork wind up with the dot pointing opposite the desired detent?   My forks were apart once, but pretty sure they were put back together right.  Seems odd that my spare right fork would be the same way (red dot doesn't land on detent pointing at a hash mark on outer fork tube ring

So I can set preload and damping on left fork with confidence, and preload on right fork.  I have no confidence in what my damping setting is on the right fork.

The damper rod was not positioned correctly(the slot in the bottom was NOT lined up with the positioning screw in the fork slider (outer tube)), therefore the red dot doesn't line up with the damping marks.... I had the same problem the 1st time I had the forks rebuilt. With the other fork preload set to min, I was able to determine what was what on the wrongly assembled fork. It just took some time and experimentating.... set and push down with brake held on a few times, reset damping and repeat....

[Shaun]

Yup I can't picture the actual alignment of the locator marks right now but I do remember there was an instruction in the manual as to which way it should be. It does work out in the end though, and I do remeber a pretty good write up somewhere about rebuilding the forks and there reassembly, If I find it I'll put it up.

[capitanoinsano]

I just got an owners manual today that I got on ebay.  Yes, I was close but not quite right.  The thinnest hash mark on fork tube must face forward (lowest damping and compression setting indicator).  If not the damping setting does not correspond correctly with the hash mark it is pointing to (red dot).  My forks are assembled right (I believe) and the problem was the position the tube was at when triple clamp was tightened.   Thanks for help.

[SlowOldGuy]

I was close but not quite right.  The thinnest hash mark on fork tube must face forward (lowest damping and compression setting indicator).  If not the damping setting does not correspond correctly with the hash mark it is pointing to (red dot).  

That's not a function of the fork tube position, it's a function of the orientation of the damper rod within the fork lower.  You can rotate the tube to line the red dot up with a fork cap line, but unless you know the position of the damping setting, it may not be correct.  The thinnest line does not have to point forward, it needs to line up with the lowest damping setting on the damper rod.

My forks are assembled right (I believe) and the problem was the position the tube was at when triple clamp was tightened.   Thanks for help.

Yes, I believe your forks are assembled "correctly" (in so far as they are working correctly) but the damper rod position is not "correct."  Rotating the fork tube will fix the problem; however, adjusting the rotational position of the fork tube so the damping indicator (red dot) lines up with the "correct" damping setting line on the cap is your dilemma.

DavidR.

[Shaun]

You know for something that has far less moving parts than say and engine, I think I have read more questions and comments about forks than almost anything else. And each time I learn a little more, I think that it really is the concept that gets caught in the thought process.