CB450 K1 Front Shock Seal Change

[Tracks450]

I'm in the process of cleaning and refurbishing my front shocks. There didn't seem to be an oil leak but the bike sat for 30 years. The oil inside was clean but the O-Rings were missing from the top bolt. Someone was mucking around but I have no idea if they changed the seals.
Now my question, the manual says to use a special tool to remove the chrome seal housing. I can get the housing to turn but it just spins. How does it come off?
PXL-20230130-220611158.jpg

[ancientdad]

The earlier models had external springs, I'm assuming yours does as well. If that is the case (and I'm not sure which manual you're using), this is from the section of the '68 to '75 FSM about the K1 version of the forks. Once the internal circlip is removed, you use the upper tube as a slide hammer to pop the seal out of the lower leg.

[Tracks450]

I believe mine is like that.....under the chrome sleeve....that I'm not sure how to get off without damaging it.

[ballbearian]

I believe mine is like that.....under the chrome sleeve....that I'm not sure how to get off without damaging it.

Is there little (like 1/8") holes around the chrome for a pin spanner? If not it isn't threaded and probably is held by an Oring and just pops off. Wrap it in rubber inner tube or make some wood blocks with a hole saw.

What does this special tool look like? How does it work?

[Juneaudave]

Looks to me like the spring (#16) needs to come out before the cover gets removed. Can't tell from your pic where you are at on disasembly....https://images.cmsnl.com/img/partsli...75122_0fe3.gif

[ancientdad]

He doesn't post many progress pictures as I've mentioned to him previously, but in the picture he posted in the start of the thread the forks are out and the external springs are off the upper tubes. I suspect the chrome cover just comes off and is held in place, at least in part, by the spring when things are assembled. The pin spanner ballbearian mentioned is for the even older design where that chrome cover threads onto the lower leg, but I don't believe this model needs it.

[Tracks450]

There are no holes for a pin spanner. This afternoon I will try and slide the collar off and take a few photos of it apart.
As for more photos of it as it is now, there really isn't much point in it. I was hoping it was a common enough task someone would just say... Oh ya thats easy just do this.....

[pemdoc65]

Those covers are usually stuck to the lowers with gunk and corrosion. Penetrating oil and judicious use of heat will loosen them up, then you should be able to twist them off either by hand or with a strap wrench.

[ancientdad]

As for more photos of it as it is now, there really isn't much point in it.

I haven't replaced fork seals in anything with external springs in decades, my CL450K5 has the later damper rod version that comes apart with the allen bolt removed from the bottom of the lower leg (slider). I'm sure there are others here who have had the external spring version apart recently, but sadly not all members read (or at least glance at) every single post here so those who probably know off the top of their heads just haven't seen your question. The parts fiches often offer a little bit of insight as to the assembly of the pieces and it appears there's nothing but the springs retaining the covers, but sometimes multiple pictures from various angles can refresh someone's memory.

[Tracks450]

Those covers are usually stuck to the lowers with gunk and corrosion.

You are right. I put the shocks in my (wooden) vise and gave the covers a good twist while wearing latex gloves. Couple of tries and 40+ years of gunk let go and the covers came off.

PXL-20230201-161306679.jpg

Hopefully this post will help others in the future.

[Tracks450]

With the shocks completely dismantled I feel better about reassembling them after cleaning them out.
It appears that a PO didn't know what he was doing when working on these in the past.
The first thing I noticed was that there was no O-ring on the top bolts.
The second thing was small O-ring parts in the oil.

PXL-20230201-182118341.jpg

The third thing was that part of an O-ring was pinned under the bottom stop, as if the PO tried to undo the bottom screw, couldn't get it out as the stop was spinning, then re-tightened the stop and wedged the O-ring part underneath.
I used the 1" PVC pipe to wedge the bottom stop into the end, to hold it in place while I tighten the retaining screw underneath. With my Ryobi Impact.

PXL_20230201_185104812.jpg

These came out of the shock, probably wouldn't have done much harm being rubber and all, but to do something, I have to make every attempt to do it right.

PXL_20230201_195550089.jpg

I was able to order new O-rings and fork seals from my local Honda Dealer.

[Tracks450]

He doesn't post many progress pictures as I've mentioned to him previously,

Really?

[ancientdad]

When many earlier 450 owners don't have a manual they often think the JIS screw in the bottom of the lower leg is how they come apart, we've seen it more than a few times here and it's somewhat understandable. Glad you got things apart and cleaned up.

[ancientdad]

Really?

My reference was really to the engine rebuild thread and no, after reviewing your posts I did not make a direct statement to you about it after all. Videos are nice, but when someone is venturing into a new and unusual engine for the first time as you were with the 450, lots of pictures with good close-ups often help us see things we can point out to be helpful and sometimes avoid a disaster. By virtue of my job here, I look at every post regardless of content and was likely remembering mentioning it to someone else. Your video recap shows general aspects of it going together but videos aren't as helpful for the smaller details like pictures are, particularly for adding content for the purpose of helping others in the future as you mentioned above.

[ballbearian]

With the shocks completely dismantled I feel better about reassembling them after cleaning them out.
It appears that a PO didn't know what he was doing when working on these in the past.
The first thing I noticed was that there was no O-ring on the top bolts.
The second thing was small O-ring parts in the oil.



The third thing was that part of an O-ring was pinned under the bottom stop, as if the PO tried to undo the bottom screw, couldn't get it out as the stop was spinning, then re-tightened the stop and wedged the O-ring part underneath.
I used the 1" PVC pipe to wedge the bottom stop into the end, to hold it in place while I tighten the retaining screw underneath. With my Ryobi Impact.



These came out of the shock, probably wouldn't have done much harm being rubber and all, but to do something, I have to make every attempt to do it right.



I was able to order new O-rings and fork seals from my local Honda Dealer.

Well done with the PVC and impact. Good to know it's going to be right now.