Rebuilding some old ebay cheapo Rebas and there is a serious amount of stiction. Done a full lower service and one of the bushings feels a bit rough. Previous life of these forks was as commuters and left on lockout so there was some corrosion to the stanchion surface at bushing level. I’ve cleaned the stanchions and polished them shiny (below the seals so will never see damage), but replacing the lowers there is serious resistance. Seals lubed, foam rings cleans and soaked in oil. Could it be bushings have corroded/expanded slightly?

Before I go and sand them down please offer words of wisdom. Want to run these forks short anyway as they’re going on a mess around/pump track build.

Stanchions did look slightly bowed in (2mm-ish) from crown end to axle end, although that could be a trick of the eye.

Thanks

Chris

Stanchions did look slightly bowed in (2mm-ish) from crown end to axle end, although that could be a trick of the eye

Based on this I’d say that they are bent and you’re experiencing bushing bind on the stanchions.

Can I softly softly bend the shit out of them? Or will it be a large dental bill?

Run a straight edge along the stanchion and look for daylight. If there’s nothing obvious repeat this at the cardinal clock positions and use a feeler gauge to measure any distortion. From what you say it sounds like the stanchions are deformed.

As for bending them back without damaging them further? I don’t rate your chances without specialist equipment.

Thanks. I think I’ll try each stanchion at a time in the lower to see if there is a bushing bind unilaterally. If they go in fine one at a time then guessing they’re bent

Only cost me £18 so the internals will easily make my money back hahaha

Is the bushing in one piece? could it be metal on metal? If you’ve polished smooth, I’d do the checks suggested above then try and use them a bit to see if they bed in…

No dental cover is included in this advice 🙂

Make sure the foam ring hasn’t got caught when putting the lowers back on. I’ve had this happen.

Also, if the stanchions were slightly corroded, have a look at the bushings – has any of the corrosion transferred to the bushes.

Thanks Phil, the bushings are white in colour so I assume ceramic or plastic?

Will hopefully have a little time this afternoon for more investigation and can report back.

Thanks teethgrinder. Both bushings white, but one has green specks on it. It maybe a design thing I’m not sure. There was an area of roughness on one bushing (almost like bubbling through corrosion), so that may be an issue with such tight tolerances. I appreciate worn bushes lead to rattles, but has anyone had corroded bushes which have required a little light sanding or filing?

Ps tempted to remove the foam rings all together and pack the groove with grease. May remove variables!

Bushes are normally an aluminium alloy coated with a hard-ish polymer (I think). If you’ve cleaned and re-used the foam rings, depending on what you clean them with, they can go out of shape.

I had a similar of huge resistance to travel after lowers maintenance once. On taking them apart again I found one of those circular springs that holds the outer lip of the main seal inside one of the legs, trapped between the slider and stanchion. Must have been got in there during manufacture because both my seals had them installed.

Anyway, TL:DR is take them apart again and look for foreign bodies stuck inside.

depending on what you clean them with, they can go out of shape

they always seem to stretch when I’ve tried.. if you’re replacing the seals less of a pain but if you’re just giving a good clean I always find cleaning them is not worth the effort as they just end up way more fiddly to put back…

Thanks all.
Foam rings were pretty bent out of shape so i’ve ditched those for now. No foreign bodies that i could see so all back together.

As the stanchions have seen better days is it good practice to add more oil to the lowers than prescribed? RS says 5ml 15wt but i’m thinking a little extra won’t hurt? OR WILL IT? mohaha

Cheers all

I sometimes find it hard to get the stanchions into and through the seals. I normally pop the springs off the seals and up the stanchion leg which makes it easier to get them into the lowers – then pull the springs back down and seat them.

If your past the seals and then it starts to bind then that doesn’t sound great.

Hahaha….got them built up, oil in lowers, air back in, feeling pretty plush, only to realise i’d put the crown on backwards! Bollocks.