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Onyx rear hub service

29K views 58 replies 18 participants last post by  happyriding 
#1 ·
1) How often?

2) What needs to be done?

I've looked at the Onyx service videos, but they don't show the steps necessary to get at the sprague clutch. It looks like you have to take the bearings out.

Has anyone done a rear hub service? How did you get the bearings out?

I've got some persistent creaking in my drivetrain, and the only thing I haven't taken apart and cleaned is my rear hub.

Thanks.
 
#37 ·
It sounds like water. You have some options to help prevent or minimize water, dust etc. from ever reaching the bearings. After installing or serving your bearings, place a liberal smear of bearing grease over the bearing seals and on bottom of your end cap before installing. This creates a barrier between the elements and your bearings.

Perhaps being more conscious of where wash water goes.

Obviously, not the same hubs as yours, but you should have some type of endcaps. Press endcap in and clean any grease that squeezes out. That grease is your barrier against the elements. I dunno about the hole in the hub?

1913844


1913846
 
#44 ·
When I emailed Onyx to find out:

Hi Tim,

That hub has the following bearings

6902

6805

6804 – center bearing, replaceable here at Onyx only.



On the non-drive side there are two different variations. The 6804 version has be serviced here – that’s the red hub in the attached picture. The 6902 version is field replaceable – that’s the Antifreeze Green hub in the attached picture.

Thank you,



Dan Peterson

Sent from my moto g(7) power using Tapatalk
 
#51 ·
Just come across this post.
I don't know why Onyx say only they or a machine shop can replace the centre bearings, i've done several myself no problem. I have a park tool bearing spacer / bushing set and some other bits and pieces to use as spacers etc. It is not as simple as a conventional hub with 1 bearing either side that I agree, the only issue is that the NDS bearing and the centre bearing are the same size, so once the outer bearing and its locating circlip are removed, you remove the inner bearings circlip and use the puller to pull the bearing out and with a rejig of spacers etc to then pull it out through the outer bearings bore and a reverse to pull the new inner bearing through the outer bearing bore then pull into its central location. Its a bit of messing about to set it up right but perfectly doable.
 
#2 ·
I just got an Onyx hub so I haven’t needed to service it yet but I watched the vid on Onyx’s site and the process seemed quite straightforward to me. I even bought a tube of their recommended Sprague clutch grease to have on hand, man that stuff is expensive!

Anyway I’ll follow this thread to see if I can gain some insights, tips , etc. too.
=sParty
 
#3 ·
Watch their disassembly video. You need a bearing puller and a bearing press to r&r bearings and the fancy grease for the sprague. And if you have the CL boost rear hub there is 1 bearing that cannot be user removed (unless you have a machine shop). I really don’t think the noise is coming from the sprague or bearings though.
For what it’s worth, I did have powder coated Onyx hubs that had a nasty spoke noise from the spoke digging into the powder coat and maybe even the aluminum on the drive side hub flange.
 
#4 ·
Sparticus,

Did you buy the grease on amazon for $49? I can't believe it's that expensive. Shouldn't it be cheaper than normal grease because it doesn't contain additives??

farfromovin,

I looked at all the Onyx mtb hub videos but they don't show how they remove the bearings--they just show the necessary tools. I have one of those blind hole bearing pullers with a slide hammer and a bearing press, but I would like to see how Onyx actually does the procedure. I like to keep my hubs well serviced by servicing them at least every 6 months, and I'm about due, so even if the creaking isn't coming from the hub, I would still like to service my hub.
 
#6 ·
Sparticus,

Did you buy the grease on amazon for $49? I can't believe it's that expensive. Shouldn't it be cheaper than normal grease because it doesn't contain additives??
I don't know anything about grease pricing. I bought my tube of ISOFLEX LDS 18 SPECIAL A for $30.29 from CNC Specialty Store, they charged $9.49 for shipping, total $$39.78.

As for Onyx's service videos, these are the ones I've been viewing.
=sParty
 
#7 ·
Does anyone know what size bearing is used in the Onyx Boost rear hub? I just received some of the magic grease, and I've got a blind hole bearing puller with a slide hammer, and a bearing press with various sized drifts, but I wanted to check if I have a the correct drift for the bearing in my hub before I get started.

And, if anyone else is considering servicing their hub, according to this

The Drive mechanism is greased for life. It is important if you take apart you hub not to contaminate the internals. The sprag comes greased with a Long-Term ISOFLEX LDS 18 Special A grease and typically will not need to be replaced.
Full text:

Onyx Maintanence

Keeping your Onyx Hub clean and free of dirt and debris is key in maintaining its high performance capabilities.

1. Use a brush (paint brush or similar) to clean off outer components of hubs.
2. If needed you can use compressed air to blow out tough to reach crevices, being careful not to send a direct blast into bearings.
3. Wipe down the shell with damp rag.

The Drive mechanism is greased for life. It is important if you take apart you hub not to contaminate the internals. The sprag comes greased with a Long-Term ISOFLEX LDS 18 Special A grease and typically will not need to be replaced. Lubricants with additives that decrease the coefficient of friction, i.e. MoS2 or graphite are NOT possible.

With grease lubrication please take care that the clutch is not filled completely with grease: "Less is more" in this case. The clutch should be "greasy" - that's enough.
And generally: It is not allowed to use any lubricant with additives (for example MoS2 or graphite), which decreases the friction coefficient.

If you find it absolutely necessary to re-grease your sprag, please make sure you have everything available before doing so. Once you have your materials, disassemble the hub and remove the sprag. Be careful not to remove the spring around the sprag cage as this will cause the individual sprags to fall out. Clean the sprag using WD-40 and blow out with LOW pressure compressed air. After it is dry, fill the empty space with in sprag with the LDS 18 Special A grease. You want to achieve a 60% fill ratio. Here are the steps!

1. Clean outside of hub and driver before proceeding, this is to keep any debris out of hub during the next steps.

2. Remove Driver side Bolt and widget.
3. Pull and rotate CCW the Driver and remove from shell.
4. Using an ID bearing puller, remove the outer support bearing. You may need to LIGHTLY apply LocTite or similar to the outer portion of the bearing during reassembly.
5. Using a small flat screwdriver, remove the snap-ring from the sprag sleeve.
6. Remove sprag from hub, noting direct of the tails (should be pointing to the left). If you put in backwards you will have a Left hand drive hub!
7. Do NOT remove the spring that is located around the sprag.
8. Place sprag in a container of Mineral Spirits and gently aggitate. Once clean, use WD-40 to rinse it off.
9. Use LOW pressure compressed air to finish off the cleaning, being careful not to blow the sprays out of the cage.
10. Clean inside the hub as best as you can with a lint free towel.
11. Regrease the Sprag using LDS 18 Special A grease only, filling the empty spaces with about 60% grease.
12. Put snap ring back into sleeve, making sure it's fully seated into groove.
13. Install outer bearing, if loose, use a small amount of bearing compound or Loctite.
14. Clean off driver and wipe down with lint free cloth.
15. Insert driver and rotate CCW while pushing in.
16. Install driver side widget and bolt.

Making sure to keep everything clean, reassemble the hub.
 
#8 ·
Does anyone know what size bearing is used in the Onyx Boost rear hub? I just received some of the magic grease, and I've got a blind hole bearing puller with a slide hammer, and a bearing press with various sized drifts, but I wanted to check if I have a the correct drift for the bearing in my hub before I get started.

And, if anyone else is considering servicing their hub, according to this

Full text:
Did you ever find out the size? I need to replace my hub bearings and would like to order before I pull the old ones out.

Thanks.
 
#11 ·
Just curious if anyone has done any maintenance to their hubs. I'm going on 2-years and they still are still silent with no play (I haven't touched the bearing pre-load).
Yes. I had to replace the drive side bearing. Pretty simple, but it was years before I had to do so (4, I think). Because of this, the axle shaft was slightly corroded, making it a bit tough to get the bearing off. You can only service the outer bearings. You'll need to send in your hub to replace the internal one or the sprag clutch.
 
#13 · (Edited)
Check your drive side cap for looseness, in their vids they show loctite used for that cap when threaded on. Took one of my wheels of today and outside axle had broken where it threads into the cap, broken piece was extracted with fingers. I would check this wheel for axle looseness somewhat regularly, tightened several times. Noticed this drive side bearing rough and does not appear to be ceramic hybrid from the P/N just generic no brand 6902 RS. Either the cap came loose enough to cause failure or bearing caused it, possibly shitty external axle.

I have a second Onyx(both SS) on another bike with much less miles on it maybe 200, that cap was finger tight but no wiggle when thru-axle tight, also did not appear to have had loctite applied was finger loose, need to tear down more as once tightened feels a little rough maybe, this one had Verinent 6902RH hybrid ceramic. On first hub rest of bearings were Enduro ceramic hybrid LLBs, not great but not bad like 3 out 5 IIRC on Enduro's grade scale.

Crap back top my insufferably loud Hope Trials SS which was broken once in same manner, now has steel outer axle so at least bombproof.

All are 142 hubs

Edit: It would appear break occurred within the width of the bearing, only ~1mm of Aluminum at break




Edit 2: Reassembled broken pieces, it looks like cap was threaded on as a far as it will go. The gap between the cap face and shoulder on the outer axle looks is 0.25" on my calipers or 6.3mm, bearing is 7mm wide so it must have been tight together at time of breakage, so looks more like a shitty-part/toasted bearing. Threads are clean in the exposed portion in previous pic so threads were almost totally engaged into axle cap.



Edit 3: It appears the first generic bearing may be Onyx in-house brand like below but the Onyx branding was worn off due to the axle break


 

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#14 ·
Tore down second hub and that one has all Verinent brand hybrid bearings, non-drive side bearing in the second one is the one causing the rough feeling not horrible but noticeable, now the choice of replacing or run it more. Outer axle etc are in good shape on 2nd hub.

The first hub probably has 1000 miles or so on it, second a couple of hundred maybe. I'm a clyde(north of 225# suited up) so maybe factory bearings not durable enough.
 
#15 ·
In my two sets of Classics, I've also had the non-drive side bearing out of my older set get that not-so-fresh feeling. Replaced it with a spare I had laying around, but I have since purchased a SKF MTRX that I plan to swap in there one of these days. That seems to be the most vulnerable bearing. I've also done the MFU retrofit to run MicroSpline on that hub, it eliminates the axle and cap threads on the drive side.
 
#20 ·
Why don't people put GOOD bearings in their hubs, instead of the trash from Enduro?

There is an easy fix to this problem, and it doesn't involve no-name or Enduro bearings.

Sent from my iPhone using Tapatalk
Pray tell, what's your fix? So far out of 2 hubs and 3 bearing brands the only bearings that didn't fail were the Enduros
 
#29 ·
From all the reading I've been doing in the last couple of days, even from Enduro's website the ceramics all seemed geared toward roadies. Enduro states that for thru-axle application a steel cage for the bearings is better as it keeps the bearings aligned more consistently and the only version of theirs that has that is their ABEC 3s. Their ceramics and ABEC 5 tend to have shitty seals and/or weak cages but are aimed at frictionless spin for those 120KM races, not for the dirt, grime and off road pounding. Most, if not all of the competitors mentioned above use the steel cages and as far as I can tell from specs most are about an ABEC-3 rating though not many use that scale for MTBs likely nothing above that really necessary. C3 tolerance/spacing seems to be the other common spec. So ironically within the Enduro brand, if you use their "best" bearings you'll likely smoke them faster all things being equal with that brand.

Going by the bearing wear in these hubs the Verinent and Onyx in-house Ceramic Hybrid bearings are even worse than the Enduros CH.
 
#31 ·
No attraction to ceramics, that's what the Onyx hub come with. I was just reading up on the pros and cons wondering why they were using them in the first place, seems like a miss spec. Actually will be replacing with all steel bearings.
 
#32 ·
I've had an onyx Classic front & rear. Single speed at rear, 135mm. Both front bearings gone in less than a month.

Rear freehub bearing also jammed solid (axle bearings ok) - onyx warranty their bearings for 1 month. That's confidence!

Replaced rear 6805 (just a cheap steel) and went out tonight. Already grinding and ticking.

I love the silent freewheel but not sure how to solve the issue of eating the freehub bearing.

Anyone have any pearls of wisdom?
 
#36 ·
I was amazed by the or condition of the inside of the hub, there's a drain hole so obviously this is a two-way street.

Orange, rusty deposits - maybe from the ball carrier in the bearing? Certainly felt like the ball carrier had failed, jammed. With 'gentle' persuasion once it was removed i did free it off, it spun ok but was notchy/gravelly.

I brush and hose it down after most rides but no pressure washer.

Didn't check inside the bearing. Will do next time - in about 3 weeks when it happens again. 🤔

When they're working, they're excellent! I bloody love these hubs so I'm keen to find a solution.

I've just bought another classic for my new gravel bike so hoping I haven't made an expensive mistake.
 
#40 ·
Honest answer.... I don't really know!!! Lol

Picked up some used onyx classic hubs and and to give them a full service Inc replacing the bearings. I kinda want to have the parts I need before i start pulling things apart so was trying to get a feel for what I might need!!
 
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