85 XR600R showa shock rebuild - Help needed

[xrflogger]

I took my shock off to rebuild it after it started leaking but also want to look into an excessive slow rebound issue. The clicker at the bottom of the shock didn't seem to have any effect either...

The shock generally seems to be in great shape.

Problem is I'm starting to wonder if I messed something when I spun off the metered nut on top of the shaft. You can see in the pic the nut has a half moon slot inside, this mates up with the half moon shaped rod end extending from the shaft. Soooo...how do you get those two mated back up when you put the nut back on? What exactly is the deal with this special orificed nut??

Also I've read some about the rebound needle seizing up in the shaft in this type of shock.

Is there anyone out there with some experience with this Showa shock? I'd really appreciate any info or data on this shock!!! (85-87 XR600R Showa)

[xrflogger]

Really need some advice on this one if anyone has input. Its riding season here in AZ and my only shock is tore apart on the bench! Did all the old Showa guys get put out to pasture?

[mog]

Never seen anything like it

[xrflogger]

Never seen anything like it

I also have an 88 XR600 shock and it has this same type orificed nut setup. What I know is that the rebound dial clicker at the bottom of the shock spins the rod that you can see sticking out of the top of the shaft - It mates into the half moon in the nut. When you turn the rebound dial it spins the disk in the nut (see pic) to a different position presumably changing the flow throught the nut. Wish I knew more. This was the XR shock for several yrs, till '91 I'm guessing. If I don't get any more info off the various forums before all my seals and bladder show up in the mail I'll slap it back together and declare myself the expert on pre 91 XR shocks ?

Edited January 7, 2015 by xrflogger

[miklaver]

i have an 82 zr500r and my shock has the same set up, i got it at the local honda shop and the kid there said i am missing the c clip that holds the rod inside the shaft but when i took it apart i swore ther was nothiung holdoing that little rod in. do you have anything holding your rebound rod in .the shaft?

[xrflogger]

i have an 82 zr500r and my shock has the same set up, i got it at the local honda shop and the kid there said i am missing the c clip that holds the rod inside the shaft but when i took it apart i swore ther was nothiung holdoing that little rod in. do you have anything holding your rebound rod in .the shaft?

No. nothing visible without taking the shaft apart at the base

[shockdoc]

Spin the washer inside the nut (from the threaded) to where you can see the largest hole from the window on the other side of the nut. Note where the "D" shape is on the rod then stick a small scribe in the window to hold the spinning washer from moving. If you are careful you can then spin the nut on the shaft slowly and wait for it to barely touch the rod and then move the adjuster along at thee same time as the nut & usually it will lie up....this is how I always do it because its quicker for me BUT

 

The way it's suppose to be done is to peel back the lip that holds the spinning washer in (on the closed side of the nut) and then take a large punch (just slightly smaller than the shaft hole (12mm) and then tap the guts out through the top of the nut. Once thats done you can then put the nut on & tighten it to spec. Then put the washer back in the right position and tap the peening lip back down to hold everything in.

 

Hope I explained it well enough to understand....lol

 

doc

[miklaver]

So that is a great Explanation on how to put it back together but my shock guy says there should be some kind of c lip holding the rod inside the shock shaft. With that said when i took it apart there was nothing holding that small rod inside the shock shaft.

[shockdoc]

Never seen one on that end but possibly once you take the clevis off since that would be the end the reb rod comes out...

 

doc

[youngmic]

Well I'll be buggered.

No doubt you have sorted this issue out by now, but ironically I have just posted an almost identical thread over on the XR forum with the same questions with the same pics about the same bike.

With a full restoration in progress on the XR600RF the shock was next on the list, my shock was overhauled by a shop 5 years ago due to a leak. Upon opening it up a few days ago I found the piston/valve assembly had been put back together upside down, but what stumped me was the rebound damper adjuster nut as it appeared to be non OEM, I am now not so sure as yours is the same, unless yours is not a true 85 shocker, that internal rebound spring has me wondering. These nuts were supposed to have the peening from the shaft removed to get the nut off, but looking at these two I can't see why. See attached diagram I dug up on the net, it was all I could find but it differs from what now appears the reality.

Whilst your piston/valve assembly looks the same as mine (mine a mid 85 Australian model) your shock incorporates an internal rebound spring, mine does not. The 85, 86 and 87's were pretty much the same unit as I understand but changed from 88 on. I have a service manual for a J or K model which looks very much like yours in that it incorporates the rebound spring. I wonder if your shock is the original 85 shock or one from a slightly later 88 onward.

Shockdoc or XRflogger or anyone else for that matter confirm the shim stack order as after discovering my entire assembly had been installed inverted I would like to be certain that the stack order is correct before reassembly. Even better still if some can offer an improved valve shim setup suited for 100kg rider racing over fast heavily whooped up desert surface (Finke Desert Race Australia) Any service pics description of the system would be also very gratefully received.

Shockdoc, re. that rebound nut do you know the torque value? I also note that as I hand tighten that nut with the piston valve assembly now installed the right way up that the internal adjuster shaft seems to bottom out in the top of the nut causing the adjuster rod to bind up before the nut is tight. My thinking is to file down the top of that adjuster rod such that it inserts into the D recess but without binding. This is a one way path though, the other way would be to shim between the nut and the round washer.

All and any wisdom and advice would be gratefully received, I have owned this XR600RF for 22 years and hopefully for another 22 years so learning and retaining knowledge of these early 600's is a good thing.

Edited February 13, 2015 by youngmic

[miklaver]

I do know they started adding in that spring in 83 shocks. I know this because i picked one up thinking i could install on my 82 xr500r and the shock is 1 inch taller and could not fit in chassis. For the rebound shaft I know when I took mine apart there was nothing holding the shaft inside the shock shaft. I dropped it off at a local dealer and he would not charge the shock because he said there should be a c clip holding the little rod inside the shock shaft. So i rebuilt the shock and charged it just fine with no problems. It was hard to get the half moon to line up with the piston nut but it is doable.

[Moneypitkx250]

need some help rebuilt the bike from a pile of junk just about. I rebuilt the rear shock "had no oil in it when opened it up" got it back together put on bike went to set the sag and when it gets pushed down it is leaking oil from from the bottom looks like above the aluminum pice that mounts to the swing arm and the nut above it. Can't find any thing about a oring or seal there please help.