Wearin' out the forks
1 - 12 of 12 Posts
Joined
·
107 Posts
Aren't the bushings supposed to protect against that kind of wear on the tubes? new Bushings don't seem so easy to find and buy as forkseals and I wonder why....yours really look clapped out and might even be wearing at the walls of the forks too.
Joined
·
7,825 Posts
Yeah, that's what I thought.
I didn't know the bushings were hard to find. They're still listed at Ron Ayers. I just changed out the worn ones for the ones I had taken out some years past when I last rebuilt the forks. They are in much better shape. Really I should be looking into some more forks 😆.
sorry but it just looks like normal wear on forks with a high mileage to me, the wear on the tube is only 0.1mm so well inside the point of no return, also the bushes are supposed to wear first being softer than the tubes.
the wear is on the part most rubbed by the bushes (first 4in or so) and where the ride height usually is, seen far worse than than yet still being serviceable. usually caused by dirty fork oil. new bushes and seals should fix it.
pyramid sell bushes for the EX used them myself they always fit.
try the bushes you have, fit them then place the lower fork in a vice pull out the top shiny part and see how much side play there is along the tube. from fully out to fully in. if there is very little play they will be fine and just require new seals.
if the play is noticeable new bushes are required.
the gen 1 has more wear than yours but work perfectly well with new seals and bushes.
FYI I got into the habit of changing the bushes every time i changed the seals no reason not to with an oil change in between swaps never had fork seal issues on any bike I owned.
E-bay item no 283870434395 is the full set I used on the gen 2.
the wear is on the part most rubbed by the bushes (first 4in or so) and where the ride height usually is, seen far worse than than yet still being serviceable. usually caused by dirty fork oil. new bushes and seals should fix it.
pyramid sell bushes for the EX used them myself they always fit.
try the bushes you have, fit them then place the lower fork in a vice pull out the top shiny part and see how much side play there is along the tube. from fully out to fully in. if there is very little play they will be fine and just require new seals.
if the play is noticeable new bushes are required.
the gen 1 has more wear than yours but work perfectly well with new seals and bushes.
FYI I got into the habit of changing the bushes every time i changed the seals no reason not to with an oil change in between swaps never had fork seal issues on any bike I owned.
E-bay item no 283870434395 is the full set I used on the gen 2.
Joined
·
7,825 Posts
@yorkie Thanks, I do appreciate your optimism in saying the forks are acceptable. I still would rather not be seeing this wear. I need to correct some math, as you're describing the wear as twice as bad as it actually is.
I believe you're correct in saying the wear is due to the oil. Not only was the oil dirty but was showing properties of a broken-down oil. I could take a picture of it, but I don't think the pic would do it any justice.
As it stands now the forks are rebuilt and back on the bike. It is my plan to just run with it and see what happens. Running into any riding issues would mean an immediate shut down. Hoping to get at least to next year's winter break down. In the meantime, come up with a plan for a better rebuild. Whether that be to find a different set of used forks to rebuild (I'm leery about the crapshoot on that) or bite the bullet and spend $600 on brand new inner fork tubes. I can go as far as to say this, I'm not getting any kind of side-to-side wiggle free play with the forks completely reassembled. I didn't think to check this while the main spring was out.
I didn't measure the length of the wear, but I can say it's in the area of ~2.5". I know that this can't be seen in the pic, as the pic is not to scale and doesn't even show the full length to use as a reference.
The diameter of the tubes went from 36.96mm to 36.87mm. Making the difference 0.09mm. I get it, you just rounded up. Perfectly acceptable, I'm going to do the same thing to keep the math simple. We have to take the diameter difference of 0.1mm and divide by 2 to get the actual wear. The wear being the actual reduction in the thickness of the metal. The wear on the tube is 0.05mm.
I believe you're correct in saying the wear is due to the oil. Not only was the oil dirty but was showing properties of a broken-down oil. I could take a picture of it, but I don't think the pic would do it any justice.
As it stands now the forks are rebuilt and back on the bike. It is my plan to just run with it and see what happens. Running into any riding issues would mean an immediate shut down. Hoping to get at least to next year's winter break down. In the meantime, come up with a plan for a better rebuild. Whether that be to find a different set of used forks to rebuild (I'm leery about the crapshoot on that) or bite the bullet and spend $600 on brand new inner fork tubes. I can go as far as to say this, I'm not getting any kind of side-to-side wiggle free play with the forks completely reassembled. I didn't think to check this while the main spring was out.
yes you're spot on the corrected maths would make it 0.045 but seeing as the heavy chrome coating is around 1.0mm to 1.5mm thick it's hardly worn out, some wear is inevitable what is it now around 145k miles.
all I'm trying to say is don't over think this. it's hard to tell from a not to scale photo I agree but I estimated the wear point on an approximation of the bottom bush being 1in deep. or 3 to 4in exactly where you would expect it to be (between the bushes) when the forks are assembled.
new bushes would have been preferable but not essential if the ones used showed no wear marks. it also may be prudent next time the forks are off to fit drain screws to the btms (like on the gen 1) so you can change the oil without stripping down the forks.
now serviced I don't see these forks giving you any issues for many more miles to come, if you had seen the state of the gen 1 forks when I first got the bike oh boy I almost scrapped them but decided just to try and bring them back into service. I removed the rust on the tops with tin foil and vinegar filled any pits with JB weld and smoothed them down with 4000 wet and dry used wet with some soap. cleaned out the btms and repainted them. reassembled the forks with new bushes and seals fresh 20w oil and just hoped for the best, 38k now on those junk legs without any leaks or issues so yours should be fine.
as an after thought if you really want to replace them at sometime in the future consider having the tops re-chromed instead of replacing them. it's trick used by classic restorers when new parts are unobtainable got to be far cheaper than new ones.
all I'm trying to say is don't over think this. it's hard to tell from a not to scale photo I agree but I estimated the wear point on an approximation of the bottom bush being 1in deep. or 3 to 4in exactly where you would expect it to be (between the bushes) when the forks are assembled.
new bushes would have been preferable but not essential if the ones used showed no wear marks. it also may be prudent next time the forks are off to fit drain screws to the btms (like on the gen 1) so you can change the oil without stripping down the forks.
now serviced I don't see these forks giving you any issues for many more miles to come, if you had seen the state of the gen 1 forks when I first got the bike oh boy I almost scrapped them but decided just to try and bring them back into service. I removed the rust on the tops with tin foil and vinegar filled any pits with JB weld and smoothed them down with 4000 wet and dry used wet with some soap. cleaned out the btms and repainted them. reassembled the forks with new bushes and seals fresh 20w oil and just hoped for the best, 38k now on those junk legs without any leaks or issues so yours should be fine.
as an after thought if you really want to replace them at sometime in the future consider having the tops re-chromed instead of replacing them. it's trick used by classic restorers when new parts are unobtainable got to be far cheaper than new ones.
Joined
·
499 Posts
Looks like you've got it covered for now, but I wonder if a local hydraulic cylinder repair shop would be willing to take on a pair of tired fork legs at a decent price. They see worn chrome plated shafts every day of the week; its what they do. It seems everything motorcycle has a stratospheric price attached ($600.00 !) but to a cylinder shop they'd be just a couple of shafts. No harm in asking.
Joined
·
107 Posts
yes, I have often meant to ask a HD mechanic about this and who locally they would goto...front end loaders and the like must be wearing them or getting pits often enough.
Joined
·
499 Posts
Just as another data point, Racetech lists new aftermarket EX500 fork stanchions (TNK, Italian) for $183 per tube. There's also a US outfit (Frank's Forks, formerly Forking by Frank, lol!, that have been around forever) but ask you to phone for a quote.
1 - 12 of 12 Posts
