Topic: BIG chunk of missing metal in fork

[Wbflyer]

Just took off my fork boots and found this large chunk of metal missing.  Should I replace the fork or just keep an eye on it.  Want to make sure it's safe but don't want to have to spend on a new fork either.  PO didn't tell me about this...

[CycleRanger]

Ouch! Do you have the missing piece?

Wonder if that happened when someone changed the seals....
I wouldn't want to keep that in the long term, personally I'd look for a replacement.

[RandomOrbit]

I'd replace that. Didn't I just see a couple of sets in the For Sale board?

[Wbflyer]

shoot that is what my gut says to do but thought I would ask. The PO said he changed the seals so I am sure that is how it happened but thanks for telling me....

[Gordon]

The PO said he changed the seals so I am sure that is how it happened but thanks for telling me....

Good ol' PO's!    It's a good thing you took the boot off.

[Wbflyer]

I know!  I just ordered a left (disk side) fork off of ebay for 50 bucks. Now I must learn how to change the fork seal.

[jgger]

When you do change the seal make sure you put it in right side up. It might be the damage I'm seeing, but it looks like the seal is in upside down.

[754]

Makes you wonder what else he "fixed"
 I usually drill 2 tiny holes in the metal part of the seal, then screw in sheet metal screws, and use a claw hammer and shim to pull the seals up.
I have never seen one damaged that bad.

[BomberMann650]

Someone failed to apply heat before removing the old seal. 

[Old Moe Toe]

Well if it makes you feel any better I managed to break a bit like that off my guzzi fork slider years ago. The seal sits just below the missing chunk and still holds oil so I live with it. Also like yours the dust boot covers the damage, which makes it a bit easier to live with. If I were to ever sell the bike I reckon I would fess up about the damage to the new purchaser,  but seeing I've had it for 34 years so far I may never need to worry about that. Being a bit particular about my bikes I would liked to have replaced the fork slider however the forks are vintage marzocchi's and you seldom ever see them for sale.

[strynboen]

alvays take a heat gun and burn the ols seal so it softens up..then it easy to pull up..or take the leg off the bike..its just the bottom umbrakko bolt..and you can pull it dovn .make all Work easyer.

.that underleg is toast. it vill leak oil

best to  find a old used one...and get the year modell right..there is thange in the internal parts abaut 76-77 i think it vas..

only chance is to use a thin seal..and hammer it dovn in the non broken part of the groove..looks like there is some left to hold a thin type seal..7mm breit one..they are not as good as the thik12mm thik ones..but can do the job..eventuell make a nylon spacer to take the free room/fill up up to the clip ring..i have done it  on my 550..

[Wbflyer]

thanks all and for the pics!  I've been searching for a video on removing the lower leg and replacing the seals but can't really find on on a 78 CB750 online.  I found a 78 decent left fork on ebay and ordered it.  I can get mine ready in the mean time by removing the lower leg and reuse the stanchion.

[RandomOrbit]

I always just used a tire iron to pop out old fork seals. I don't remember it being difficult, and the tire iron didn't mar the surface of the fork. I guess if they really don't want to come then heat would be the thing.

[Bankerdanny]

I usually just use a large flat bladed screwdriver to pry out the seal. I fold up a shop towel or rag to help prevent marring on the surface of the lower.

As far as right side up. The last few seals I have used have had springs and lips springs on both sides of the seal so as best as I could tell it didn't matter which side was up and which was down.

I believe that Randakk has a tutorial on building a seal removal tool over at the tech tips section of his site: http://www.randakksblog.com/removing-gl1000-front-fork-seals/#more-1164. It is intended for GL1000 GoldWing forks, but they are very similar and the tool should work on SOHC4 forks just fine.

[Wbflyer]

Ok, I will follow that tutorial and see if it will help on a 750

[BomberMann650]

If ya use heat the seals practically come out by hand.

Works the same putting the new ones in! 

All this reading stuff and making tools has me giggling.  Here with my $10 heat gun.

[CycleRanger]

Looks to me like the PO didn't know there was a retaining clip.....

[Wbflyer]

The thing is, you would have to really use a TON of force to make that happen.  Seems like the seal would break before the metal.

[BobR]

When you do change the seal make sure you put it in right side up. It might be the damage I'm seeing, but it looks like the seal is in upside down.

 Been a while but I believe they are double sided seals (lips and springs on both sides). That said they are still probably directional. Bob

[Stev-o]

Typically the text on the seal should be on the top