GPZ 550 fork caps

Yay, great weather. Not quite that bad here in Chicago.

I took some photos in case they might help.

Here's the cap with no o-ring. (The air valve is not screwed all the way in in this photo.)

Here's the open tube.
Inside:
The 1st ring you see is the clip ring.
The 2nd ring you see is the step where the I.D. reduces to press in the o-ring.
The 3rd ring you see is another step to reduce the I.D. to the normal I.D. of the fork.

The o-ring normally resides between the 2nd and 3rd ring.

Here's how the cap looks when it drops in. Without the o-ring, it just falls in to where you see it in the photo. There is very little play, but it is definitely not tight at all.

The shoulder (near the top) on the fork cap rests on the firs I.D. reduction step. The shoulder is the only part of the cap that comes near to the wall of the fork tube.

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Here's with the o-ring.
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Here's how far it drops in without pressure with the o-ring installed. The o-ring stops it from going any further unless you press it. It only takes a few pounds to press it in past this point. (That is without the springs installed.)

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I have about a dozen of these forks and they all look the same (from 1981 KZ550D gpz, 36mm O.D. forks). If yours are different then maybe you have forks from a different bike?

loudhvx wrote:

I have about a dozen of these forks and they all look the same (from 1981 KZ550D gpz, 36mm O.D. forks). If yours are different then maybe you have forks from a different bike?

Nope, same forks, that's them exactly. I know they're original,plus I've got a back up set.



Spring in, washer in, O ring on, pressing down. That's as far as she goes. It appears the cap won't make the transitions from the middle ring to the lower ring. It doesn't matter if the spring is out or the O ring is off. I'll go fiddle with it tonite

Well, my mind is boggled.

please let us know what you find when you get the time.

What ever happened with this? What was the issue? I was thinking o ring was too big, but you said it wouldn't go in without the ring.

I was a victim of beer

My FIL was helping me take it apart as it was gummed up after 20 years and he snapped off an air valve.

So I took off both air valves to clean everything up and put the valves in the bottom of the caps

After much cursing, and posting, I finally went to my spare front end, popped out a cap,saw what I did, went D'oh and had it up and running in about an hour.

40 years of wrenching and I stll have to watch myself

glad to hear you didn't completly fork up!