Want to change the fork oil . . .

[red]

 . . . and don't really want to die trying.  A guy might expect this job to be simple, but not by any of the books that I have.  Sure would be nice to have some qualified bike techs around, so if anybody knows of a decent bike fixer (or bike shop) in Utah, I'd be game.  Most nearby bike shops have rotten reviews posted, and/or rotten reputations, period.  The shops don't care what people may say, because there are so few choices here.  Even a good shop in SLC would still be an hour+ away from me

Before work even starts, there is a black plastic "PROGRAM" cap on the fork tubes, and none of my manuals seem to include any references to them, or a final setting when finished.    Is this a stock item for an 1985 FJ1100, or is this a mod?  Are there any tech manuals for them, or the final settings when finished?  A Search of past posts gave me no good results.  Any help (and maybe a good mechanic here) would be appreciated.  Picture of the PROGRAM cap:



Cheers,
Red

[HARTLESS]

. . . and don't really want to die trying.  A guy might expect this job to be simple, but not by any of the books that I have.  Sure would be nice to have some qualified bike techs around, so if anybody knows of a decent bike fixer (or bike shop) in Utah, I'd be game.  Most nearby bike shops have rotten reviews posted, and/or rotten reputations, period.  The shops don't care what people may say, because there are so few choices here.  Even a good shop in SLC would still be an hour+ away from me

Before work even starts, there is a black plastic "PROGRAM" cap on the fork tubes, and none of my manuals seem to include any references to them, or a final setting when finished.    Is this a stock item for an 1985 FJ1100, or is this a mod?  Are there any tech manuals for them, or the final settings when finished?  A Search of past posts gave me no good results.  Any help (and maybe a good mechanic here) would be appreciated.  Picture of the PROGRAM cap:



Cheers,
Red

That cap is just that, it pops right off. Doesn't even really need to be on there....

[FJ111200]

Under that cap is an adjustable hex that is used to set the suspension to hard, medium or soft, and in the centre of that hex is the thing that adjusts the damping.
That "thing" is slotted to aid adjustment with a flat head screwdriver, and has a dot to help alignment with marks on the hex.
Both of these should be set same point to get the correct adjustment for the suspension.
Hope you can understand that.

[markmartin]

Red,

Check out this thread: http://www.fjowners.com/index.php?topic=4072.msg35737;topicseen#msg35737

The work doc. write up attached to the first message on this thread will give you an idea of what things look like in there:http://www.fjowners.com/index.php?topic=1911.0

Mark M

[red]

Under that cap is an adjustable hex that is used to set the suspension to hard, medium or soft, and in the centre of that hex is the thing that adjusts the damping.
That "thing" is slotted to aid adjustment with a flat head screwdriver, and has a dot to help alignment with marks on the hex.
Both of these should be set same point to get the correct adjustment for the suspension.
Hope you can understand that.

FJ111200,

Maybe not.  Would I be changing these settings, just to do the dis-assembly?  If so, how would I know if I got things (such as pre-load) set correctly, when reassembling the fork caps?

Mark M,  some of those pictures work, some do not, and some only show half-pictures.  Is the fork oil change procedure the same on a 1989 and a 1985?

I see that fork oil levels are measured with the fork compressed.  The manual gives a only a volume (424cc) to fill, not a distance.  Does anybody know what the oil level should be, with the forks fully assembled, and fully extended?

Thanks,
Red

[racerrad8]

The settings will not change if you are just removing the cap. The adjuster rod just spins unless you depress it and engage the internal lock to turn it. So you can remove the cap without changing the settings.

You just need to make sure you install the "D" shaped adjuster rod back into the center of the damper rod at the bottom.

The average setting of the fork level oil compressed is 6" from the top. That is adjustable to help you tune the forks.

Randy - RPM

[red]

The settings will not change if you are just removing the cap. The adjuster rod just spins unless you depress it and engage the internal lock to turn it. So you can remove the cap without changing the settings.
You just need to make sure you install the "D" shaped adjuster rod back into the center of the damper rod at the bottom.
The average setting of the fork level oil compressed is 6" from the top. That is adjustable to help you tune the forks.
Randy - RPM

Randy,

Once you open a can of worms, you always need a bigger can, to put them back . . .   

On one side, the center slotted rod can be turned with a common screwdriver, maybe ten degrees either way with little resistance, and if depressed a few mm, seems to engage into a slot below, which I did not try to turn.  From your description, I am guessing this is normal.
On the other side, the center slotted rod can be turned only a few degrees, with some force applied, and can not be depressed at all.  This part seems to be locked somehow.
I have not yet raised the front wheel off the ground, after discovering this difference.  The front suspension seems to work normally, though.

Thanks,
Red

[Flying Scotsman]

I think you got one side wrong and the rod is not in the d shaped hole.

[red]

I think you got one side wrong and the rod is not in the d shaped hole.

Flying Scotsman,

That situation may be the case, but I have not even started the job, yet.  The best way for me to proceed from here, would be most useful.
Would it make any difference to lift the front wheel, to get the rod re-set properly?  What should be done next?

Thanks,
Red

[Flying Scotsman]

I would take the forks apart and fix them.If you need seals do that too.If you dont need seals all you have to do is remove the top of the fork with a rear axle nut inside the big hex drain the oil so you can see and re instal the rod making sure its turned the same as the D shaped hole.You will know you got it right if the  top piece slides down to the threads and you can screw it in.Fill with oil then screw in top.I would remove forks to do it I think it would be more difficult in the bike.

[rktmanfj]

If the rod is in the wrong hole, you're going to have to pull the cap to fix it anyway.

http://www.fjowners.com/index.php?topic=1267.0

[markmartin]

Red,
Unless you want to do one fork tube at a time, which is possible, you're going to have to suspend the front wheel. If you remove both fork caps without  suspending the front, your bike will fall on its nose, as the caps hold the springs in and the springs hold the bike up/  I've never done it one at a time, but I suppose you could do it that way, just use the volume measure for fork oil listed in the manual for refill and go with that.  

The word doc. link that I sent you to works on my end, --I'm not sure why you are getting 1/2 pictures....

I can't answer your question 'are the forks on an '85 the same as an '89'.  Sorry. I think you've got anti-dive on your forks and the '89 forks don't // I'm not sure how that effects this procedure, but I"m assuming not a lot. ?  

I don't know why your preload adjuster is not turning, however, when you take this all apart, you'll have a better understanding to what's going on in there and what's up.  Also, you'll see how easy it will be to install some of Randy's springs and emulators if you ever get the want to.

[Flying Scotsman]

85 and 90 are not the same.Similar though.Oil capacity and viscosity not the same either.

[movenon]

Here is a nice little stand that "markmartin" came up with (at least that's who I stole the dimensions from)  

There some variations on the stand.



George

[red]

(continuing...)

I removed the plastic caps (thanks), and broke loose the 27mm fork cap, but did not remove it.  After some attempts to rotate things, I find that all parts inside the cap rotate, when the cap is rotated.  I would guess this is normal, but more knowledge will be welcome.  The center rod (with the common screwdriver slot) can now be depressed, against some spring pressure.  It is not as free as the other side, but at least it is not bound up, as before.  There is a hexagon ring (which I colored blue, for clarity, in the picture below) around the screwdriver slot.  This ring rotates, and can be unscrewed upward, independent of any other parts.  I have not removed it yet, and before I do, I need to know the function of this ring.  Any advice is welcome, here.

I am working alone, so if the top cap nut must be removed, I will need a shop to do it for me.  I only want to change the fork oil, really.  If I have to get the forks rebuilt with all new o-rings and seals, I may as well have Randy's fork valves installed then, too.  I can't spare the money for that work, now.

Thanks,
Red