Fox Fork Bushing Installation Tool
I have a spare fork that I bought awhile back and am just now getting time to overhaul it (2002'ish RockShox SID SL). I noticed it's starting to wear the stanchions at the bushings so I'd like to replace the bushings. But, this is something I've never done.
While the bushings are cheap (about $15 for the set), the actual RockShox tools to remove and replace the bushings will cost me over $100 and that doesn't include the parts I can't find (bushing install sleeves). The MTBR forums usually have a solution to my problems. After searching last night and this morning, I found that Bad Mechanic had previously posted some excellent ideas on how to remove and install the bushings yourself. Here's his recommendation for removal. Take a washer which is the same diameter as the bushings. Grind flats into the side of the washer on opposite sides so it looks like this: Put a washer on a long threaded rod, and keep it from falling off the end with nylock nut. Take the fork's lower and angle the washer so it can slide past the bushing (the reason for the flat sides) and then get the washer flat and pull it up against the bushing's underside.
Once there you can either use a slide hammer to pop the bushing out, or put another washer and nut on the threaded rod and tighten it down on the top of the lower and pull the bushing out like that.And, his recommendation for installation. This is a little more involved.
There are a couple ways to do it. The route I went was taking the old stanchion and JB Welding several old bushing onto it, one bushing's height from the bottom. I used fine sandpaper to knock off the slick coating on the inside of the bushing and the outside of the stanchion, and then used hose clamps on the bushings for 24 hours while the JB Weld set.
I then drilled holes through right through all bushings, and glued metal rods in place, and ground their ends flat with the bushings. It's probably overkill, but it works. I then used sandpaper to slightly reduce the diameter of the bushings. Before extracting the top bushing, I'll place my installation tool in the lower and mark the top edge of the lower with a Sharpie on my installation tool. I then remove the top bushing.
FOX redefines ride dynamics for ATVs, mountain bikes, motocross. Insert the pusher portion of the DU removal tool through the DU bushing in the shock eyelet. Que es stop motion.
Then I repeat the above procedure with the lower bushing. Then to install, I put the new bushing on the installation tool and set it at the correct height using the Sharpie mark on the tool, and then the same for the top bushing.Well, I can follow those directions. Out to the garage.
I measured the inside of the lowers (not the inside of the bushings) and it was about 30.5mm. I found a washer that was larger than that, secured the washer to a bolt with a nut, and chucked the bolt into my drill. While spinning the washer I laid it on a coarse file and started shaving down the washer. I'd stop every now and then to see how much more I had to go. Once I had it down to 30mm, I used my bench grinder to flatten it on each side. Finished by sanding off any burrs.
Put it on a long piece of all-thread and put a smaller washer behind it just to add some stiffness. Fits nicely into the lowers.
Secure the other end of the all thread into a vice. Tap, tap, tap at the top of the lowers with a rubber mallet. Out comes the upper bushing. Out comes the lower bushing.
Overall, they came out much easier than I had anticipated. The top bushing was flush with the lip of the lower and I took the measurement of the lower bushing (from the lip) before removing it.
I ordered the new bushings today and I'll use the time (and the old bushings) to fabricate the installation tool. Special thanks to! To be continued.
Donor fork is a Spinner Aeris Sport. The SID stanchions are 28mm and these are 28.5mm.
I figured I would need to sand on the donor stanchions a bit in order to get the epoxy to hold, anyway. Should work out fine. I couldn't figure out how to get the lowers off. Want to know the beautiful thing about disassembling a fork that you don't care about? You can cut that s.o.b.
And take a peek inside! Peek in the drive side. Huh, not connected to anything. No wonder the nut was just spinning around (ha, spinning. I made a funny.) Peek in the non-drive side. A shaft of some sort. Oh, how can we solve this?
I'm enjoying this, can you tell? For anyone actually trying to disassemble an Aeris Sport without a hacksaw, I could tell later if you remove the cap on the non-drive side and reach wayyy down there with a (I think it was) 6mm hex head you could actually unscrew it and remove the lowers gracefully. I removed all of the other pieces and parts (had to break some other things. Muahahahahah!) and then cut a slot in the crown and tap out the steerer. The new bushings are in the mail. But, I have a few other projects I need to tend to before I can get back to this one. It may be awhile before I update the thread.
Finished painting the fork lowers (more info ). What I was going to do: Using the caps that came on the stanchion, I was going to rig up a way to spin the stanchion using a drill and then gently file it down to 28mm. What actually happened: A kind soul on here took pity on me and volunteered to turn it down using his metal lathe.
I won't mention his name (so he's not inundated with lathing requests ). But, I am very grateful as I'm sure the final product will be much better than what I would have cobbled together. He let me know it's finished and should be shipped back to me sometime soon. Once it arrives, I'll finish out the bushing installation and snap some photos.
If I have time, I might try to turn the other stanchion down just for grins and to see 'what would have happened'. I didn't have time to try and turn down the other scrap stanchion.
But, I did receive the finished tool in the mail. It's beautiful. If I would have been able to make a functional busing driver from the other stanchion, it would have looked nothing like this. Who was the kind benefactor of this wonderful tool? None other than, himself.
Sir, thank you very much for assisting with this. If anyone on here deserves some +rep, it's you. I sent a loose stanchion and one old bushing and this is what he returned to me. And, yes, it works as good as it looks (see next post). I do have a question. This is the first time I've replaced fork bushings and when I put the stanchion back in the lowers I have to use a very 'firm' push or pull to get them to move.
They're not sticking. There is just absolutely no play. Is this normal? Can anyone chime in with some sage advice?It is possible, depending on the design of the lowers, that the bushing surfaces in the lowers have a slight taper that allows you to adjust bushing fit. I have not done the 28mm SIDs but the you do seem to be able to tighten or loosen up the lower and upper bushings on the 32mm SIDs by slight (eg.
0.5-1.0mm) bushing insertion depth changes. Provided the bushings and stanchions are generously lubed in fork oil (or Mobil 1 if that takes your fancy), then I adjust the bushing tightness so that there is no discernible slop but almost no resistance. The lowers should almost slide off the stanchions under their own weight. If the bushings are any tighter then you may have an insufficient gap to get lube oil in there. They may eventually loosen up, but will wear prematurely. I did some more reading last night and your advice is spot on with what I've read. The lower bushings are fine.
It's the upper bushings that are a bit too tight. I'll tinker with it some more this weekend to see if I can get them setup a with a little less 'grip'.Before pulling them out, I'd slide the lowers down far enough that the lower bushing isn't engaged, and then push the lowers back and forth and side to side to make sure the top bushing is well seated. Or, remove the lowers entirely, and use the tool to do so. I think I have it fixed. I went ahead and tapped out the upper bushings and tried the stanchion lower bushing to see how it was fitting (it fit fine). I then put some 15wt fork oil on a clean rag and wiped the inside of the lowers and the outside of the bushing. This definitely helped me drive it in gently and in small increments.
After resetting the bushing, I used the tool to work the bushing from side to side to ensure it was seated. The stanchions then slid in the bushings as I expected. I must have driven the previous bushings in just a tad too far. Thank you all for your help! I'm making my own tools based on this thread. Thanks for the detail!
I have a couple questions about the installation tool though. The tool is essentially a scrap 28mm stanchion with an old bushing attached as a stop for the new (loose) bushing as its driven in. Isnt the outer diameter of the old bushing (now part of the 'tool') the same as that of the new bushing. And doesn't the whole assembly therefore get hung up when driving the new bushing down into the lowers?
Is the old bushing mounted to the stanchion/tool spun down to have a slightly reduced outer diameter to make the tool more maneuverable within the lowers? Also, how much force is required to drive the bushings into place? I'm trying to gauge how well i need to fix the old bushing to the stanchion to make the tool. I'm imagining JBW should do it, but if it's enough to require a significant whack with a hammer, i might drill out the stanchion and put a pin through to hold the bushing in place. The tool is essentially a scrap 28mm stanchion with an old bushing attached as a stop for the new (loose) bushing as its driven in. Isnt the outer diameter of the old bushing (now part of the 'tool') the same as that of the new bushing.
And doesn't the whole assembly therefore get hung up when driving the new bushing down into the lowers? Is the old bushing mounted to the stanchion/tool spun down to have a slightly reduced outer diameter to make the tool more maneuverable within the lowers?I didn't actually build my installation tool (Bad Mechanic was kind enough to build it for me). But, I was prepared to follow the directions he had posted in another thread. Here they are. There are a couple ways to do it. The route I went was taking the old stanchion and JB Welding several old bushing onto it, one bushing's height from the bottom. I used fine sandpaper to knock off the slick coating on the inside of the bushing and the outside of the stanchion, and then used hose clamps on the bushings for 24 hours while the JB Weld set.
Fox Fork Bushing Reamer
I then drilled holes through right through all bushings, and glued metal rods in place, and ground their ends flat with the bushings. It's probably overkill, but it works. I then used sandpaper to slightly reduce the diameter of the bushings.
As he instructed, JB Weld looks to be a viable solution to adhering the old bushing to the scrap stanchion. Regarding the width, he also says to use sandpaper to slightly reduce the diameter of the glued bushing.
This should keep the installation tool from becoming jammed in the lowers. Please post the outcome when done. I didn't actually build my installation tool (Bad Mechanic was kind enough to build it for me). But, I was prepared to follow the directions he had posted in another thread. Here they are: As he instructed, JB Weld looks to be a viable solution to adhering the old bushing to the scrap stanchion.
Tools, Supplies & Kits
Regarding the width, he also says to use sandpaper to slightly reduce the diameter of the glued bushing. This should keep the installation tool from becoming jammed in the lowers. It didn't take much force at all. Removing the old bushings took a few strong whacks with a rubber mallet. But, the installation was much gentler taps (as I recall).thanks a lot. I'd seen his previous thread, but somehow missed the comment about sanding down the old bushings. It may be some time before i get to actually put this all into action.
I really have my work cut out for me with this fork project! I have plenty of garbage RS spares laying around.
But it seems like there may be an inherent advantage to using the larger stanchion, turned down to 28mm, since that would create a lip for the old bushing on the tool. Do either of you guys think that's a material advantage compared to just using a 28mm stanchion with an old bushing just JBW'd in place?The stanchion I sent Bad Mechanic was actually 28.5mm.
He turned it down to the proper size. I have the other stanchion hanging on the wall in my garage. I'll never use it but I just can't bring myself to throw it away. If you want it, let me know and I'll ship it your direction. The method i used was successful, though it comes with a caveat.
The bushings did not bond as well with the stanchion tube i used for the installation tool as i'd hoped. They hung on long enough to drive the new bushings into place, but the tool did not survive the job to install another set of bushings in the future. I did manage to get the bushings pressed into place without too much trouble, but the process was a bit ugly for the final bushing, as the tool was coming apart. For anyone attempting this, i'd say it's totally doable with the DIY tool i made as a one-time job, but if you have more than one fork to work on, a machined tool would be the better solution. I think i could have done a slightly better job with JBW-ing the old bushings to the stanchion. Maybe it would have bonded better.
Getting the teflon out of the inside of the old bushing to make a good bonding surface was really the hardest part, and i think the biggest contributor to the ultimate failure of the tool. I think if i spent more time cleaning out the teflon so that the JBW had a better metal-to-metal bond, the tool may still be hanging on my workbench to install another set of bushings in the future. FWIW, when the teflon is removed from the bushing, the thickness of the bushing is reduced enough to slip in and out of the lower with ease, so no sanding of the exterior of the old bushing on the 'tool' was necessary for me. Yes, pinning the bushing in place would definitely do the trick for a permanent tool.
Overall, even with the tool failing, it wasn't much of a hassle. For people looking to hit the 'easy button' on this job, i'd say just do it the way i did, and expect the tool to suffer a bit through the process. You may struggle a little bit, but getting the bushings into place didnt require anywhere near as much precision as i originally anticipated, so the inferior tool wasnt really an issue.You're totally right on that, and the bushings could always easily be re-glued if necessary to finish the job. You're totally right on that, and the bushings could always easily be re-glued if necessary to finish the job.one bit of insight i really should add is that if you're using the DIY tool with just JBW (no pin), when pressing the bushings in, make sure to have the slot in the new bushing OPPOSITE the slot on the old bushing, which is on the tool. I didnt think about it, and on the first one i pressed in, i had the slots more or less aligned, which i think contributed to the (old) bushing coming off the stanchion. If the slots are opposite one another, the bushing on the tool should not be as vulnerable to movement of the new bushing being driven in. Found this thread the other day and it has saved me trying to find a new set of forks.
Thanks to all the previous posters. I have a bit to add too. I've a set of Marzocchi 55 eta 2008 forks. Got them serviced by a LBS a while back and since then they have been leaking oil. There was a fair bit of rock in the bushings too. I was going to change the bushings but could be waiting 2 months for them from the UK so I decided to try resizing the current ones.
Using a tool something like that described I just gave all the bushings a couple of taps further into the lowers and it worked a treat. It didn't get rid of all the play but it's probably about 90% there. Found that the LBS have fitted the oil seals upside down so hopefully now have a pretty sorted set of forks. Moral of the story.
It seems 'resizing' is possible on old bushes. Nice find on the rings. And, rebuilding a lot of Judy's and SID's lately? We need to chat.
Without digressing too far, i've been doing a lot of restoring old rs forks for various retro bikes, or just for my garage wall. Currently on my bench is a 1995 judy sl which i'm inconspicuously converting to 2004 sid team internals for a weight weenie retro bike i'm working on (which has some covert anachronisms). I also have a minty 1997 DHO in need of a rebuild, which will end up on a 90s-dual-slalom-themed hardtail which will serve as a townie.
Overkill i know, but as my old shop teacher used to say 'anything worth doing is worth overdoing'! Feel free to PM me if you wanna geek out about any of the above.
These days most full suspension bikes are fairly reliable, but there’s one bit that regularly gives up the ghost – the shock bushings. You’re probably familiar with the symptoms – an irritating knocking noise from the back end, a distinct vertical looseness to the suspension Nearly all rear shocks have pressed-in self-lubricating bushes running on aluminium spacers. It’s a sensible design assuming that all the loads are along the axis of the shock – any sideways slop in the rear suspension will put off-axis loads through there and lead to premature bushing failure.
Some shocks have spherical bearings at the ends so that can handle a bit of wibble, but most don’t – if you’re getting through bushings at a prodigious rate check for slop elsewhere. Assuming the thing’s just reached the end of its natural lifespan, we’ve always had the best results from replacing the bushing and the spacers all at once. Generally the low-friction coating has worn off the bushing and the spacers have become misshapen with wear. Do the lot and you’ll be back to a delightful factory-fresh tight rear Don’t forget that. 5.Place a suitably-sized socket or spacer over the opposite side of the shock eyelet (it needs to be big enough for the bushing to pass inside it) and one of the old alu spacers in the new bushing.
Get the whole lot in a vice and gently squeeze. The new bushing should drive its way into the shock eye, pushing the old one out as it does so. It’s a proper tight fit but once it’s started it should slide in relatively easy.
A proper big bench vice is a usefuly ally. In an ideal world the new bushing will be ever so slightly narrower than the shock eyelet so when it’s flush one side there’s a hint of a step on the other to give the next new bushing a start.
6.With a shiny new bushing in place, it’s time to push the new spacers in. We took the opportunity to replace the alu spacers with a mounting kit from ( do a similar kit) that uses a steel shaft through the bushings with an alu spacer each side so that the bushing’s running on hard steel rather than soft alu. This should extend the life of the whole assembly considerably.
Whichever you choose, it’ll be a snug fit at first and may need pressing or tapping in (or through). Don’t apply any grease or lube to the bushing surface – it’ll just cause the coating to break down and flake off.