Fork bushings

Despite marketing claims that the 2023 RS forks are a new and improved design, I’ve had a few people tell me their bushings are mega tight and need burnishing to be usable.

Same mentioned over in the MTBR burnishing thread.



Marketing.

Engineering

Manufacturing.


All on different planets talking different languages.



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teK-- said:
Really they should just add the extra 10mins in production time per fork to burnish the bushings. It would result in so many more happy customers and brand retention.
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Like the young dudes that wash your car after a service.

Poke that metal bar in there carefully.

Happy customers, get a $600 service done on your car... visible value for money = 0

Car washed after the service... they did a good job :D
 
Speaking of bushings. Check out a set of replacement Onyx lowers they sent me a while ago....good luck burnishing that!
391716

To be clear(apparently it isn’t), this fork leg has had two lower bushings as well as the upper bush fitted. The stanchion wouldn’t even go into it! After that they sent me Diamond lowers…yeah they didn’t fit either. Got there in the end though.
 
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Do we have a measurement for correct clearance? I get that out of round is also an issue but are we talking .040 or .005? I've got nfi what it should be.
I'll stick the bore gauge down my lowers the next time a do a service
 
komdotkom said:
Do we have a measurement for correct clearance? I get that out of round is also an issue but are we talking .040 or .005? I've got nfi what it should be.
I'll stick the bore gauge down my lowers the next time a do a service
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fox states you want diametric tolerance, so the sum of both gaps to be between 0.0381mm and 0.2286mm. No apparent distinguishing between various stanchion diameters. I've seen claims tools 0.1 to 0.165mm bigger then stanchions are desired. I've so far had no issues with 0.1mm. So for 36 stanchion that measures 36.03, I'm using a tool that is 36.13

Measure the stanchions, lots are on the piss. Not parallel, out of round that varies along the length, one forward of the other. Also pay close attention to what the hub spacing does to the lowers/uppers fit.
 
The tool I made is 35.07mm. I've used it 3 times during successive 50hr services (probably 6 "passes" each leg). Each time the tool gets easier to push through the bushes.

0.1mm is the largest tool head I would be willing to burnish bushes with.
 
fjohn860 said:
The tool I made is 35.07mm. I've used it 3 times during successive 50hr services (probably 6 "passes" each leg). Each time the tool gets easier to push through the bushes.

0.1mm is the largest tool head I would be willing to burnish bushes with.
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I took confidence with Oliver saying he had sold over 200 tools with heads all at 0.1mm over the nominal dimensions, many to stores, not one complaint. With fox's upper limit being 0.2286mm, and so many stanchions being on the piss, 0.03mm is swamped by other issues I feel.
 
link1896 said:
I took confidence with Oliver saying he had sold over 200 tools with heads all at 0.1mm over the nominal dimensions, many to stores, not one complaint. With fox's upper limit being 0.2286mm, and so many stanchions being on the piss, 0.03mm is swamped by other issues I feel.
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Yeah, agreed. 0.1mm is fine (fuck all to be exact :p)
 
Reviving as have a related problem. Anyone here able to both replace & burnish bushings, or have a recommendation for a shop who can?

The new Fox 36 Rhythms I bought (secondhand unfortunately, no invoice) have been causing me grief - there's significant knock when you rock the fork back & forth, and feels rather loose when riding. Definitely not the headset too. After pulling them apart 3 times now, have come to the conclusion that the bushings are so loose in the left leg that a gap opens up in the seal & oil weeps past. Seems to be causing issues with lubrication too, after riding for a while they gradually start developing this lovely creaking sound/feeling, which goes away as soon as you flip the bike upside down to get some oil back up near the seals.

Any ideas on what to do?
 

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Not helping with the bushes or burnishing but a 'stickier' oil like Supergliss 100k might help.
 
ozzybmx said:
Not helping with the bushes or burnishing but a 'stickier' oil like Supergliss 100k might help.
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Thanks, tried Supergliss 68k (air side only, damper requires 5wt teflon) which didn't weep as much, but didn't alleviate issue with knocking/creaking either - possibly worse. 100k would probably be slightly better in this regard, but it has been only 10-15deg down this way too so 68k tends to work better.
 
I have a few forks here that have been cast aside due to the lack of small bump and general harshness. Was looking at the RMS burnishing tool but $155 postage from Canuk.

@fjohn860 @link1896 did any of you guys ever get around to making additional tools ? Looking at 36, 37 and 38 heads and the handle just needs to be functional, not a work of art.

Thinking the 0.1mm on each of the heads would do the job.

Let me know if anyone is up for making a handle and the above heads before I order one from somewhere.

Cheers
 
I believe Mark (Link1896) maybe close to getting his new workshop set up. I couldn't wait for my new build and ended up getting Cylinic to burnish my forks, but I would still be keen at grabbing some tools to keep on hand for in future and for mates' forks.
 
teK-- said:
I believe Mark (Link1896) maybe close to getting his new workshop set up. I couldn't wait for my new build and ended up getting Cylinic to burnish my forks, but I would still be keen at grabbing some tools to keep on hand for in future and for mates' forks.
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Mass production, there's 2 for back order ;)

Could maybe add a 35.1mm head to that list too.
 
ozzybmx said:
I have a few forks here that have been cast aside due to the lack of small bump and general harshness. Was looking at the RMS burnishing tool but $155 postage from Canuk.

@fjohn860 @link1896 did any of you guys ever get around to making additional tools ? Looking at 36, 37 and 38 heads and the handle just needs to be functional, not a work of art.

Thinking the 0.1mm on each of the heads would do the job.

Let me know if anyone is up for making a handle and the above heads before I order one from somewhere.

Cheers
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Mattyp said:
If @fjohn860 keeps churning out burnishing tools at his current rate, he could retire...very poor.
I see a market for Australian hand-made precision tools... $$$
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I've made 2 complete tools (one for me and one for a certain lurker on here), a fox 40 head (with a different interface for a suspension service centre) and a 37mm that fits my original tool.

@Mattyp is on the money there. Definitely no margin in making these (on a manual lathe). If anyone was serious about paying their full wage when making these they'd have to sell them for ~$600.
 
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