As above, any first hand experiences?
My bike came with an XTR FH-M9111 rear hub which has always gone zzz zzz zzz. Reading the MTBR posts to return it to silent operation sounded easy enough, but it hasn’t worked for me.
I’ve tried removing various bits, then oiled the freehub, all that’s happened is the freehub now goes zzzzzzzzz.
Any ideas for further playing?

Grease, not oil, inside the pawl mechanism usually works.

I love a hub buzz though me.

Too much grease can also cause problems with pawl engagement.

I’ve always preferred quiet freewheel’s but a recent purchase had a Hope Pro4 on and it actually sounds lovely when it spins up and spins forever. Not quite the bottle of angry wasps some describe. But I like it.

Grease, not oil, inside the pawl mechanism usually works.

I think the latest Shimano hubs are different, the original idea was the ratchet ring would completely disengage from the drive. If you imagine the drive ring in a DT hub “floating” just disengaged from the hub so the two halves buzz past each other. In the sylence system, the ring is on angled splines so the ring is actively pulled back when coasting and pushed in when pedaling.

There was some issue with making it work in the real world though so Shimano bodged it with a spacer so now it’s not silent, more like an evolution of the DT system.

If you packed it with thick grease it just wouldn’t slide in/out at all.

Unless it was a patent issue with Shimano? The Onyx Vesper hub is a silent-clutch hub and I’m thinking of using one to rebuild my Reserve rear wheel.

Peripheral to the OP, but I’ve made the wrong-lube-in-a-freehub mistake before. I always use Shimano special freehub grease now.

I dread to think how expensive those tiny pots are at the moment post-Brexsh1t though, it was painful enough a few years ago.

My XT hubs are silent with no fettling required. A quiet bzz when going slowly (walking pace) but anything above that, nothing. It’s beautiful 😄

Sorry, not all that helpful…

Yeah, thanks ossify 😉
It is indeed the drive ring on angled splines affair, with the right friction combined with the right spring pressure I can see how it would disengage to a silent mode, and still re-engage.
But can I do it with only the parts provided in the hub?
What happened finbar?

Unless it was a patent issue with Shimano? The Onyx Vesper hub is a silent-clutch hub and I’m thinking of using one to rebuild my Reserve rear wheel.

Very different design.

Onyx use a sprag clutch, kinda like a lot of pawls with blunt ends so there’s no ratchet for them to clatter over but the friction is enough to engage between the freehub’s axle and the hub shell.

DT have two ratchet rings pressed together by a light spring so they clatter over each other. It’s part of the DT patent that’s expired and means a few brands are starting to offer similar hubs.

Scylence has 2 ratchet rings but the helical splines on the freehub push* the two together. When coasting the inherent drag in the bearings slides the drive ring the other way so there’s zero engagement (and a light spring that pre-engages it when stationary or very low speeds). The downside as it turned out was it works in prototypes and on XTR levels, but for the mass production XT level it was problematic so they added a spacer to hobble it and dropped the name. The mod the OP hints at is to take the spacer out but my understanding was (I ended up not needing new hubs so didn’t have to do it myself) it didn’t always work and was a bit of a lottery (hence Shimano added the spacer).

*it’s actually a pull as it’s inside out but that’s harder to visualize.

Nice one, thanks for the detailed explanation. Everyday is a school day 🙂

It’s a lottery as to how those hubs are going to sound. Some go quiet at speed when new, others make a constant sound, and my old one did the annoying zzz—zzz—zzz—…. Mine would also creak loudly under pressure which would get solved by taking the whole thing apart, including the ‘do not take apart or lubricate’ bits, and IIRC lubricating with Dumonde Tech freehub grease and oil. I think after I did that the hub was just constantly noisy, but that was much better than creaking and fluctuating buzzing. Shimano really dropped a ball on this hub.

I’ve just got a brand new XT hub and it’s not silent at all. I watched a video where the guy spun the wheel up fast and then stopped pedalling and there was no noise, only when the wheel slowed down did the clicking start.

I tested that on mine today and it did not go silent. What I did notice though was that the pitch changed like it was changing gear as it slowed down. So instead of the pitch going down continuously as it slowed it went down a bit and then jumped back up. It did this two or three times as it slowed down.

Well I put my bike together in the house then wheeled it to the garage. Almost silently.
Somehow the freehub knows the difference between you spinning it in your fingers or the bike freewheeling along.
I’ll go for a ride this weekend and see if if catches fire/ kills any baby robins/ me. At least if it does let go the bike has such a short stem that I reckon my gentleman parts will be safe.
I still don’t know what is meant to be so special about freehub grease and oil, seems to be the thinnest waterproof stuff that won’t thicken over time, which sounds like Castrol CL to me.
For the sake of disclosure I used GT85 on the freehub as it was nearest.

Well I survived unburnt, as did the baby robins.
Had a winch & mince session and it was grand, exactly the same engagement but silent downhill.
I’ll do the job properly with some thin suspension grease in the rachet, and waterproof grease on the seals soon, but for now I’m happy.

Update for anyone still reading.

Dismantled the ratchet tonight, cleaned it with contact cleaner, greased it with some Manitou suspension grease I had.
Result; totally silent but turned out to be unreliable engagement. So…

Dismantled, cleaned, lubed with Putoline HPX R 20W fork oil.
Result; a moment of zzz then silent; reliable engagement.

Next thing will be to try a thinner oil, I’ve got some 15W and some 5W fork oil, and I’m becoming a dab hand at splitting the freehub.

When you look at the ratchet mechanism there is a little retainer c-clip with “do not lube” and “do not dismantle” written on it. This can be compressed to pop it out of its groove with a small flat bladed screwdriver. Under that is a retainer clip with 2 tabs holding it in place, the same small screwdriver inserted into the recess by either of the tabs will lever the clip out with no damage. Then the ratchet comes apart to be cleaned and lubed.

👍

Update for oceanskipper and anyone else interested.

Re-did it with 5wt Putoline HPX fork oil tonight, got a result 🙂

It gives one z before going silent, when you spin the wheel up in the bike there is a very quiet zzz but riding it it’s silent.

I think I’ve worked out what does what inside, and what lube does for the job.

There are two springs. The outer one just holds the outer ratchet ring in light contact with the freehub body.

The inner one transmits drag from the hub to the inner ratchet ring.

When dry the inner spring and slider ring creates almost no drag, and the zzz noise occurs.

The drag induced by lube on the slider ring on the end of the inner spring is enough to cause the angled splines to do their thing, and separate the two ratchet rings during freewheeling.

I also oiled the angled splines, although thinking about it this may create drag opposing the separation of the ratchet rings, I’ll clean them off sometime to see what effect that has. If they don’t need oiling then you don’t need to split the freehub mechanism 🙂

Also oil or grease the outer drive dogs of the outer ratchet ring, as the hubs can creak otherwise.

I left the two ratchet faces dry, as any gumming up in the future would cause engagement issues.

From taking the wheel out, cassette off, freehub off, ratchet mechanism split, cleaned with contact cleaner, oiled, all rebuilt and wheel back on takes about 20 minutes, so easily worth a go and fully reversible if you want the noise back.

Interesting result, thanks. Do you think Shimano just decided not to make it silent for whatever reason…?

Mine is a bit noisier than my MT501 and definitely more of a “waspy” zzzz because of the number of engagement points. I don’t mind it particularly but I do wonder if it’s worth taking it to bits to add more lube – mine is literally 10 days old though so I don’t want to ruin it….!

Various theories out there, the factory fire, unreliable due to greater shock loading when stamping on the pedals*, who knows?

Right, here’s the final instalment…

Ratchet mech dry and clean as supplied from Shimano.

Just grease the drive dogs that key into the hub body to prevent a future creak, I ended up oiling the slider that sits between the inner spring and the inner ratchet ring with 20wt fork oil, then added a smear of grease too, to thicken it a little.

Reason is just oil = constant quiet buzz, just grease = silent but amazing levels of drag, enough to make the chain sag I would think.

*The angled splines work in three phases, the more separation drag = more backlash = slightly greater angle of engagement = more room for a bike masher to stamp on the pedals and shock load it. I don’t ever stomp so it doesn’t matter to me, but I imagine Shimano wouldn’t accept the risk.

I haven’t got this hub but a good read none the less.👍

Do you think that the hub being fairly picky over oil etc might result in erratic engagement in a fairly short time? I wonder if a significant rise/ lowering in temperature might effect things if viscosity changes?

Just thinking aloud really as I can’t sleep.lol

Quite possibly. I’ve got loads of good motoX fork oil from days gone by, it should find life on a bike pretty easy in comparison.

What I’ve ended up doing doesn’t affect engagement, pedalling force through the angled splines will overcome any stiffening of the lube (oo-er) and the ratchet internals are now dry so should always engage cleanly.

Hopefully any changes in the ‘draginess’ of the lube will only affect the noise or lack of it.

@Poopscoop, reading all that about a hub you don’t have must have sent you to sleep Shirley?

Lol, nope, I find these techy little posts really interesting for some reason.

Probably shouldn’t read them when I want to sleep!😀

Hi @oldnick,

Did u end up removing any parts, or simply oiling the internals?
I am looking to do the same as i have a shimano xt full wheel which is totally silent (2019), and my new hub (xt 2022) is not!!

I’ve got my xtr hub 95% silent. It only starts making noise when it is slowly rotating. Appears there is minimal, if any drag. I tried the fork oil, chain lube and grease. What worked was slickoleum (fork seal grease). I applied this to only the slider ring (no need to take apart the driver). We’ll see how long it lasts!

Is the slider ring the stepped plastic ring that sits on top of the inner spring?

I over greased the splines that fit the freehub into the hub body with too thick grease which then migrated into the freehub and actually caused the freehub to lock. I’ve since refitted it degreased and dry. Which has lots less drag. But I fear it may start creaking again.

Should the freehub stay dry as per the warning to not lube?
If I get some nice light suspension grease. Do I just want it on the slider ring? Or also on the splines between freehub and hub body?

This hub is a bit of a mystery to me! 😂 Love it when it’s working properly though.

Yes, that’s the slider ring. I have ZERO miles on this hub, just bench experience. With that, and per shimano, I believe you want shimano grease (probably any waterproof grease) on just the the spline interface. No other lube in the driver. Mine came from the factory w/ grease, and it was pretty minimal. To silence the driver, just small coating of light grease on the plastic slider ring, I also put a bit in the grove that the ring sits in.

From Shimano:
https://na.s-tec.shimano.com/s3_assets/filelibrary/Hub_and_Wheel/Microspline_Lubrication_Procedure.pdf