Topic: Fork seal replacement

[fendersrule]

I replaced some fork seals last night in the girlfriend's CB450. I drove them in evenly and gently until they "stopped", which happened to leave some space from the seal to the c-clip. I've read online that this is completely normal and that the seal should fall back to the c-clip under normal operation.

But one thing I didn't do is grease the seal cavity. Is this worth pulling out the seal with potential to damage them to grease the cavity? One thing I thought I could do is apply some grease to the exposed cavity that is visible from the seal to the c-clip which may suffice.

Let me know!

Also, the "lock nut" which is basically a half-shaped nut that screws against the spring...does that just need to be screwed in all the way and it's good to go?

I assume I may have some other installation questions later. I haven't completely dissembled forks before, but so far it appears to be something hard to mess up. Just wanted to double check some of these things.

[BobbyR]

It may be the picture but it appears that those fork tubes have some pits and scratches. If that is true you must polsih them if you expect any longevity. Basically the rule is if you can feel something with your fingernail it will cause you a problem. The forks can be polished by using very fine sandpaper coated with ATF and used in a shoeshine motion. If you have a pit too deep, you can use a solvent to remove the oil. Fill the pit or scratch with crazy glue and polish that down. My Honda dealer who is not a warm person, but a legendary wrench told how to polish them and also if I did not they will not last very long. 5 years no leaks. The first set lasted about 2.   

[fendersrule]

Thanks BobbyR.

I'll take a closer look at them, but I think they are in pretty darn good shape. Some of it may just be dust specs w/ the flash, and some of the residue from the solvent I was using to clean the tubes. I know that there isn't any pitting going on.

If I do sand the fork tubes, what grit do you recommend?

Any advice about my fork seal not getting greased?

[MoMo]

I would have used grease on the inner lip of the seal.  Unless you want to take the forks apart to do that I would not add any grease as it will hold dirt in and possibly score the tubes.  Yes, there can be room between the seal and the circlip.  That nut you are referring to needs to be tight against the top fork bolt.  Use two wrenches to tighten the nut against the crown bolt and then tighten the fork bolt into the forks.  Make sure the washers are between the gaps of the top crown...Larry

[fendersrule]

Hi Larry,

I did use ATF oil to lubricate the tubes before sliding them in. I think that was what the manual called for. I however, did not grease the outer part of the seal...I'm guessing that it not a big deal. I think I put a very small amount of grease when redoing my CB750 seals, but I just plain forgot with this CB450.

Interesting...the nut needs to be tightened against the top bolt and not the other way around. I was wondering why I found 5 washers underneath the top bolt...I don't remember my CB750 having any.

Do you guys know of a good visual source or video for doing all of this to make sure I'm doing this correctly? Otherwise, I can post some step-by-step pictures for your guys' input.

Sounds like I need to put back on the washers (I think there were 5 on each side), tighten the nut against the top fork bolt (hand tight?). This will sandwhich the washers together. Then, fill up the forks with ATF (I'll need to look in the manual to see how much), and lastly tighten the the now-assembled fork into the bike using the top bolt, and then clamp it in place from the front.

[MoMo]

As long as you used atf on the tubes you are good to go.  Those washers were probably added by the PO to preload the springs and the nut should be tight against the top bolt...Larry

[BobbyR]

Thanks BobbyR.

I'll take a closer look at them, but I think they are in pretty darn good shape. Some of it may just be dust specs w/ the flash, and some of the residue from the solvent I was using to clean the tubes. I know that there isn't any pitting going on.

If I do sand the fork tubes, what grit do you recommend?

Any advice about my fork seal not getting greased?

If there are no real pits or vertical scratches, 1200 cut into strips and soaked with ATF should work. Just use it like a shoeshine rag so you keep them round. A good chrome polish to finish them off. You really want them to look like a mirror.

I have a 78K so no grease was involved, I just coated the tubes with ATF and slid them in.

[fendersrule]

Thanks guys. The front end rebuild went really well.


I'll remove the boots and look at the tubes after a few hundred miles to see if there are any leaks. I didn't feel that any sanding was necessary on the fork tubes since they looked as good as my CB750 tubes (which I didn't sand and no leaks after several hundred miles), but I will check and use the advice here if needed.