1997 flhtcui

Have to replace a fork seal.
I drained the oil from the left leg via the bolt in the bottom that holds the damper tube in place.
When screw that back together the fork upper tube slides up and down like it should, but it's like there is no spring, there is no resistance at all, I can slide the inner tube up and down full travel.
This is dry without the fork being refilled, that doesn't seem quite right to me.
Can anyone tell me what is going on, is this normal, what/if have I screwed up?

Thanks

 

Stock, It should be air suspension. Is there air pressure?

 

Did you disassemble the fork?

Original springs?

 

It's an air system.
But there is no air in it, as the fork leg is on the bench.

 

I have not disassembled the upper leg, only separated the upper and lower legs from each other.
The spring is not stock, but is stock length, I know this because I rebuilt them about 8 years ago with new springs, later lower fork legs and ricor intiminators.

 

Not sure. I went to Progressive suspension and got rid of the air ride. I could not get the legs disassembled, and had to take to a shop to have them switch it over.

 

Walk in the part,
Star by removing 21 and up,
Now loosen tripple clamps to slighty drop the fork down to exspose the flats on 22,
tighen back up the lower clamp, to loosen 22, then you can drop the fork out of the triple clamps.

With fork loose, keep downward pressure on 22 as you thread it up and out, since you will have spring pressure on it from spring 33.
Once you have 22 out, turn fork over, to drop out spring 33 and flat washer on top of spring 24 into oil bucket, and allow as much oil to drain out as you can.

Now using impact gun and long allen bit, zip bottom bolt 12 and and make sure to pull the copper washer with it, then turn fork top side down to slide out 33-25 and 17

Now lift up rubber cap above 23 if forks have one on it, then remove clip spring 23,

Now grab lower tube18, and using inner sliding tube 32 like a slide hammer outward away from 22, you going to remove 32 with seal 31, and washer 29, bushings 35 and 30 that will come out with tube.

At this point, break out the cleaner to clean the tube and parts.

Now to reinstall using seal driver,
New 32 snapped on to end of 32, drop that down the tube 18 with a touch of fork on on both bushings, drop the bushing 35 on the tube and slide it down, install the washer 29 on the top with it dome edges upwards, then use seal drive to seat bushing 35 into 18. How lube up the tube, and drop seal 35 down the tube, then if you have an extra washer 29, can drop it top of the seal (number side up on seal) to drive the seal into place. Once seal is in place, then remove extra washer 29, and reinstall snap ring 23 and make its seated all the way into the tube.

Now on dampening rod 33,install spring 25, put 17 on end of dampening rod, slide the dampening assembly down the slider tube with it all the way down, then reinstall bolt 12 with new copper washer.
Note, use blue loctite on bolt threads if reusing the old bolts, and had tighten bolt down to start with to make sure 17 has not dropped off, and then can torque to spec. If dampening tube starts to turn as you are tighting bolt, send spring 34 down the tube to hold dampening tube in place with a little pressure on the spring.

At this point, install your fork oil to factory specs, pump the slider tube a few time up and down to get the air out, then drop spring 34 down tube 32, drop washer 24 on to of spring, and with 32 pulled upwards all the way, should have to compress the spring down about 1/4" in the tube, to start threading 22 on the top of the tube.

If you do not have to compress spring 32 to get 22 screwed back onto the top of tube, then stop, since you have an after market spring that is slightly shorter, and there should be a spacer that is used with the shorter spring on top of it between the the spring and washer, to get the required amount of spring preload to start with.


And again, like when you where removing the forks, install the fork in the tipple clamps just enough up so 22 flats are still exposed, tighten lower tripple clamp, and finish tightening 22 to top of tube, before you loosen the lower clamp again to install it all the way up.


As for air ride forks, the air pressure is used to set free sag ride height, and not so much dampening off the forks isntead. Again, spring should need to be compressed in tube, to get 22 cap threaded back on. As

As for fork oil, I use 15w in the forks to factory fluid amount, the drain the fluid out of the shocks, to replace that fluid to 10lbs at 10.5 oz per shock.

As for using drain bolt to change fork fluid, don't since forks need to be rebuild about every 30K, including pulling the forks apart to get all the old fluid out in the first place. Here is what 30K fork fluid looks like, and all is needs to be flushed out with fork rebuild, isntead of leaving any of mess behind to just be mixed with the new fluid.


Also, when cleaning up fork parts before reassembly, make sure to flush the void area between the inside and the outside of the tube as you can see on the left hand tube in the below photo.


The last one, if you do have a lathe handy, great to check to make sure tubes are not bent out of the spec, and give then a quick surface polishing as well.

 

Nice write up! Very detailed.

I appreciate when people take the time to give a nice thorough response!

 

Have you put the bolt back into the damper/bottom? The seal keeps it from sliding off the bottom unless the lock is out and you jerk on it.

The travel you have may be from bushing hitting the seal sliding to the the point its hit the damper. All this assuming you have the spring in and cap on.

And you're supposed to drain the forks from the side...

 

Did not think of that, and if you remove bolt 12, instead side bolt 26 oil drain bolt to remove the fluid from the forks, forks need to come apart.