'80 750 LTD fork seal job....wow.

[apbling]

So this weekend I decided it was time to take care of the front forks since I have the bike now running decently. I pulled the forks off the bike and started to disassemble them. After "making" a special tool, I was able to take the inner tube out. To my amazment, there was maybe 3 shot glasses of fork oil left in each one...and no air at all. Besides that, a few washers were missing that go on top of the shorter spring on the inner tube. So someone has been in there before me and must have had a few "extra" parts leftover when the job was "done". Some people amaze me....


Anyway, my questions are:
1. How do I inspecect for damage from running like this? I am not sure how much the PO road around like this. Visually everything is straight and not gouged up or anything.

2. The manual talks about a gasket that is on the allen bolt on the bottom of the lower fork housing (it screws into the inner tube). I do not have a gasket on either of mine. Can I make one out of gasket material or is this thing something special?

Thanks for your input,
Andy

[elr658]

The gasket on the lower bolt is a copper washer.

[jap4lvr]

how can there be no air? if there is almost no oil what was taking up the space.

[herk]

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[apbling]

Yes, I meant that when I cracked the air valves there was no pressure. I knew when I bought the bike the seals were leaking, but was very surprised to see that they were that bad.

Now this copper washer... Can I pick something like this up at a hardware store or is this another trip the Kawie shop?

[elr658]

It may still be there.

[red and black]

tell me about your special tool. i am just now pulling the fork apart on my 81 1100, and i tried all the tricks....broom handle in the tube, spring compressed in the strut, impact wrench, etc. all i get is the allen bolt spinning away like mad.

[apbling]

The special tool really wasn't all that special. Lets first start by saying I got really lucky. For some reason, one of them came out with no issue. The other spun like mad. So, I was looking at the head of my inner tube (the part that spins) and I noticed it actually has some teeth in it. I just got a bolt from a hardware store that the head fit snugly inside the tube. I put two nuts on the end of the bolt, used 2 3/8" extensions with a socket on the end. I held the fork that was still together at an angle and put the bolt (complete with nuts, already sitting in the socket) up the tube and wiggled it around until I felt the bolt head seat in the tube. Then I just used the rachet and an allen wrench. I hope this helps. It was incredibly easy once we did this. The only lucky break I got was we knew what size bolt to use. I am not sure if it is the same as my fork. I don't know the exact size we used, but can find out by tomorrow. This also worked really sweet when assemling, because I could actually use my torque wrench. If this makes no sense PM me and I will draw a crude picture to show you what I am trying to say.

[apbling]

elr, you have intrigued me... are you saying that the gasket is still holding onto the lower fork tube? Or maybe on the bolt. I thought I had looked close, but now I am second guessing myself.

[red and black]

Apbling, if you can get that bolt size, that would be great. i tried this trick with a welded up 17mm bolt and nut, but it was not the correct size.

[apbling]

I will take a look tonight when I get home from work. Should have it posted by 7PM CT.

[apbling]

Sorry for the late reply. My damper has a head that looks like a 19mm socket. We actually used a what I think was a 1/2" bolt (has a 3/4") head on it. Not sure if your damper is the same as mine though...hope it works. I believe 3/4" is pretty close to a 19mm...

[apbling]

I'd also like to state I am once again a dumba$$. Those copper washers were in the lower fork... oh well, I don't mind letting ppl know I'm dense, especially when things work out well in the end...

Anyway, a local guy told me to put no air in the forks. I have seen both put air and don't put air on these forums. I run about 250 lbs... I took it for a spin last night and I think the front end looks little droopy yet. I am just concerned I may shorten the life of my fork seals... thoughts?

[StarGate]

If it was designed to have air pressure then put the correct air pressure in it, even if it's at the bottom end of the pressure range. I'm not sure why people think they are better engineers than the ones that designed these systems but I'd be willing to bet that 99.9% of them are not.

[apbling]

Hehe, I am an engineer (although a young and dumb one), and I still know my place...
1. Japanese Engineering
2. German Engineering
3. Everyone else.

I'll throw some air in there tonight. Problem is I don't know how acurate my pressure gauge is. I think I remember the book saying +/- 1 psi...

Thanks,
Andy

[ironyankee]

I used an 11/16 nut welded to a piece of rod to loosen the inner fork retaining bolt.That translates to 17 mm I thinks. This was on my 83' 650 some forks use a 19mm inner fork tube-3/4 inch I thinks.I've tried air and no air in my forkys.I currently use no air and 30wt motor oil.I know it's not what the Engineers had in mind but it works for me and it's better than dealing with my local Kawasaki dealer.He's about 5 minutes away but it's probably the worst dealership I've ever been to.The man is an assh@@e and has the personality of a stump.Lazy and not caring or willing to help.Anyway I'm about 200 lbs. myself and this combo works for me.Check your spring length if you've got a lot of sag.New springs from Jeff at Z1 are 71 bucks and shipping.good price,good springs and good people at Z1.(My copper washers were stck on the outer leg too.)I'm due for new springs myself.

[red and black]

OK, ladies & Gentlemen, the magic number for GPz1100 forks is 22mm!! This is the bolt size you need to hold the plunger thingee inside the fork still while undoing the allen bolt. Of course I don't have a 22mm bolt (or nut), so I found some slightly larger SAE bits and spent 20 minutes on the grinder to get it right. After struggling for 2 nights to get fork #1 apart, let's just say I did fork #2 in 15 minutes.
Thnx to those who offered suggestions...seems each size larger bike has it's own size bolt/nut.

PS: I am also an Engineer (Mechanical). I worked for a German Engineering company for 12 years..our slogan for the occasional fixes that we had to put together over here:
"German Engineering....American Ingenuity"

[apbling]

Haha, glad to hear you got it to work. I just got really lucky for some reason... the one fork came apart with no effort, so I was able to match up the bolt head. You have a leg up on me with the engineering side of things... I am chemical engineer.

[herk]

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[apbling]

So, I went out to the garage today and noticed a small puddle under my left fork... Upon inspection I find that the allen bolt on the bottom of the fork is seeping by. I guess I'll have to open the fork up again and try to seal it up. I put liquid gasket on the copper gasket after cleaning it up and I torqued the bolt down like the manual stated. Does anyone else have any tips?