Author Topic: Replacing fork seals on CB750K1  (Read 1180 times)

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Offline pjandrew99

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Replacing fork seals on CB750K1
« on: May 21, 2017, 02:52:08 PM »
Before I totally destroy these forks, can someone provide me with instructions on how to replace the fork seals in the early cb750's?
I saw where it is not good to remove the damper on these. I did remove the allen screw at the bottom in a desperate attempt to separate the fork. No go. Looks like there is a bushing under the clip I removed. So, I can't pry out the old seal.
I'm lost.
Thanks!!!
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Offline ekpent

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Re: Replacing fork seals on CB750K1
« Reply #1 on: May 21, 2017, 03:16:34 PM »
 So you have the allen screws out of the bottoms and you have removed the big c-clips off the top of the fork seal correct ?  The next step if you have the top caps off and the large damper spring removed is to separate the fork legs from the fork sliders. This can be done buy pushing and pulling the sliders like a slide hammer till they separate. Heat/dunking in hot water etc. can help in getting the ols seals out of the legs but eventually you need to carefully pry them out with a specific tool or a screwdriver etc if they don't come out with the forks.  Do you have the forks removed from the triple clamps and bike ?  Have fun  :D
« Last Edit: May 21, 2017, 03:34:01 PM by ekpent »

Offline Nic

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Re: Replacing fork seals on CB750K1
« Reply #2 on: May 21, 2017, 03:26:14 PM »
If they are early forks you don't need to take out the Allen bolt, you simply remove the circlip and washer, push the slider down then yank it up while holding the lower, might take two or three goes if you haven't done it before, the seal will come out with the slider. That's of course after you take out the spring.

Offline pjandrew99

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Re: Replacing fork seals on CB750K1
« Reply #3 on: May 21, 2017, 03:36:09 PM »
Forks are off the bike. I have the springs out and the forks drained. So it sounds like I do a slide hammer action and that will force the washer and the seal out of the lower fork. Does that sound correct?
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Offline ekpent

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Re: Replacing fork seals on CB750K1
« Reply #4 on: May 21, 2017, 03:41:50 PM »
 The washer should basically fall out AFTER you remove the c-clip that sits in a groove that holds it and the seal in. If you have removed the round clip then slide away.

Offline jamesw

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Re: Replacing fork seals on CB750K1
« Reply #5 on: May 21, 2017, 03:46:02 PM »
When you re install the new seals be sure you have the correct side up.

For my K4 (on OEM seals) the writing faces up.
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Offline pjandrew99

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Re: Replacing fork seals on CB750K1
« Reply #6 on: May 21, 2017, 03:52:23 PM »
Hmmmm....
I think the washer stayed in. Nothing came out after I removed the clip.
Going to give it another shot.
Thanks to all!!!!!! Appreciate the help!!!!
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Offline ekpent

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Re: Replacing fork seals on CB750K1
« Reply #7 on: May 21, 2017, 04:25:57 PM »
 Maybe its stuck to the top of the seal or if they have been replaced in the past some people just leave them out.

Offline pjandrew99

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Re: Replacing fork seals on CB750K1
« Reply #8 on: May 21, 2017, 04:33:17 PM »
Great advice!
Seal came out fine.
No washer. I'll make sure I put one in.
Many thanks!
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Offline BobbyR

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Re: Replacing fork seals on CB750K1
« Reply #9 on: May 21, 2017, 04:44:51 PM »
Congratulations!  Now you need to look at the fork tubes. Run your fingers over them. If you see what looks like a scratch or rust spot you need to polish it down using fine grit sandpaper soaked in ATF. If you cant buff them out you can clean the spot well and use a drop of crazy glue on it and buff that down. If you can feel something with your finger nail, it will cause a leak prematurely.
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Offline pjandrew99

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Re: Replacing fork seals on CB750K1
« Reply #10 on: May 21, 2017, 05:34:46 PM »
Thanks. I will check the tubes out. Appreciate the info!
Did a bit more digging. I have 14mm seals which probably explains the lack of washers, I think. The seals I bought were 11mm so I need to find washers or purchase the thicker seals. Looked though some previous threads and the washers are not available. Any idea where I can get the washers? Or, should I buy the thicker seals? Another $30 to buy new seals.
Also, are thicker seals more effective than smaller seals with washers? Mute point I guess if I can't get the washers.
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Offline Jimray23

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Re: Replacing fork seals on CB750K1
« Reply #11 on: May 21, 2017, 05:38:05 PM »
If u can find a machine shop, they can usually cut new washers for u for a couple of bucks. Just need to get the dimensions

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Offline pjandrew99

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Re: Replacing fork seals on CB750K1
« Reply #12 on: May 21, 2017, 07:03:36 PM »
Thanks to all!
Much appreciated.
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Yamaha SR250
Honda SL350 K0

Offline ekpent

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Re: Replacing fork seals on CB750K1
« Reply #13 on: May 21, 2017, 07:47:37 PM »
 To be honest the thinner seals will work without the washers. Washers would be better to support the retaining ring etc..

Offline Jimray23

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Re: Replacing fork seals on CB750K1
« Reply #14 on: May 21, 2017, 08:28:30 PM »
I would of figured the washer was to act like a spacer to keep the seal from moving up and down cause excessive wear on the outer part of the seal. But i don't know for sure.

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1979 kz1000b ltd
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    dyna-s ignition
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Offline ekpent

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Re: Replacing fork seals on CB750K1
« Reply #15 on: May 22, 2017, 04:22:56 AM »
 If those large spacer washers cannot be found I wonder if our guy that does the laser printing making switch parts etc (Smudgemo) would make some of those and if they would be strong enough. Think PeWe used some nylon spacers but maybe he went to the 13.2 mm seal.
« Last Edit: May 22, 2017, 04:25:10 AM by ekpent »

Offline Jimray23

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Re: Replacing fork seals on CB750K1
« Reply #16 on: May 22, 2017, 05:15:12 AM »
If those large spacer washers cannot be found I wonder if our guy that does the laser printing making switch parts etc (Smudgemo) would make some of those and if they would be strong enough. Think PeWe used some nylon spacers but maybe he went to the 13.2 mm seal.
I bet it would work just fine.

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Jim
1979 kz1000b ltd
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    pod air filters
    4-1 open exhaust(no muffler)
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    dyna-s ignition
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Offline lash

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« Last Edit: May 22, 2017, 05:56:13 AM by lash »
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Offline Phoenix

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Re: Replacing fork seals on CB750K1
« Reply #18 on: May 22, 2017, 11:13:40 AM »
Just sayin:  when I did mine, I took them down to my friendly Honda dealer.  He installed the seals at no charge.  Saved a lot of sweating.
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Offline Nic

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Re: Replacing fork seals on CB750K1
« Reply #19 on: May 22, 2017, 03:28:16 PM »
With the double seals you don't put the washer back in, no room.