cb500 fork seals

We all have heard of the technique for doing fork seals where you remove the spring, fill the fork leg with water and hit it with a hammer to dislodge the seal by hydraulic pressure. I tried this and it wouldn't budge. The trick is to fill it with BOILING water (twice, once to preheat and once to go) then INVERT THE LEG so you don't get scalded when the water comes out, rest it on one block of wood, put another piece on top and clout it with a lump hammer. After trying for an hour or so with cold water, with boiling water it took just a minute to pop the seal! Obviously you should use gloves! Fitting the new seal, just use the old one as a drift, grinding a fraction of a mm off all round so it doesn't get stuck. Support the leg vertically (inverted again) between protected vice jaws or any suitable gap (stanchion downward, seals resting on top of vice) then hit the fork lower with a soft blow mallet. Drives the seal easily with no need for special tools. If the vice hasn't got clearance vertically, just do it sideways.. ;-)
Please note that the stanchion IS NOT CLAMPED by the vice, the vice is adjusted to be just short of touching the stanchion walls.

That's fair enough, saves stripping the leg down!

I became a past master at changing the seals over the years because the chips in the stanchions kept knackering the seals; thankfully with replacement stanchions & chip guards the last time I had to do them was 5 years ago touch wood!

The trick is to fill it with BOILING water...

Heat is amazing stuff.

Glad to hear you had success with this. Have you thought of fitting fork-gaiters to stop it happening again? I put mine on years ago and haven't had any problem since.

One thing's certain, it will be a hell of a lot faster next time I need to do it! I think they call it a learning curve. Got a few pits on my stanchions as well, but if it gets me through the MOT I'll be happy. Just as a matter of interest, did you use the "slide hammer" technique and if so does this damage/jam the bushes as some have said?

ET - Yes, fork gaiters are a brilliant idea (as are properly-shrouded forks - well I did use to ride Velocettes!) but as the stanchions are already borderline pitted, I shall save that treat until I renew them I think!

lonehelmet wrote:One thing's certain, it will be a hell of a lot faster next time I need to do it! I think they call it a learning curve. Got a few pits on my stanchions as well, but if it gets me through the MOT I'll be happy. Just as a matter of interest, did you use the "slide hammer" technique and if so does this damage/jam the bushes as some have said?

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I used the hammer technique and it seemed to work quickly and effectively without causing any damage. I wouldn't argue that it is the softest way to get out seals but it is quick and easy. Worst case you could put new bushes in anyway for little extra cost.

lonehelmet wrote:Just as a matter of interest, did you use the "slide hammer" technique and if so does this damage/jam the bushes as some have said?

Yes I did, and it didn't jam the bushes. Whether that's pure luck on my part or not who knows but i've done it that way on every bike I've worked on.

Thanks for the feedback James, an ounce of experience is worth a pound of theory any day! Only advantage with the water technique is that you don't have to remove/relocate the damper rod. The vid on Youtube for the hydraulic technique shows LOTS of force (and very messy oil!) being used, but using boiling water and pre-heating the impact required is fairly moderate, with no component damage being visible. But it does get your trousers a bit wet.... ;-)

Hi Teamster, thanks for the feedback. Perhaps it only jams if the bushes are heavily worn? Nice to hear other people's experience.

I appreciate the idea of using water as it requires less disassembly but you'd wanna be sure you got rid of all the water and any damp from the internals. I think i'll stick with the strip and hammer technique personally.

Personal choice James, I don't say one method is better than the other. Re moisture, the hot fork seemed to drain very dry, I then just gave the whole thing a flush through with some old outboard fuel and left it to drain again overnight. I don't say one method is better than the other, just trying to help anyone who, like me, found the "water trick" difficult with a well-stuck seal!

where can i get decent priced honda original fork seals....mine are on way out...all i seeing are cheap aftermarket brands and id rather go for the honda originals for peace of mind...UNLESS any1 knows a really decent set of after markets that'll do??
thanks...Starish

Little tip with sliding new seals over pits in the fork stanchions. Way I do it is to wrap a bit of greased stiff paper round the stanchion a couple of turns, slide the seal on to this then move the paper/seal assembly down to the slider. You can then easily slide the paper out before driving the seal down in to the slider.

Never fails