Shimano freehub body internals

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alexnharvey
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Re: Shimano freehub body internals

Post by alexnharvey »

ClappedOut wrote: 20 Apr 2021, 11:22pm Marine grease
What is this in reference too?
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531colin
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Re: Shimano freehub body internals

Post by 531colin »

zenitb wrote: 20 Apr 2021, 10:50pm
531colin wrote: 19 Apr 2021, 10:29am I can't avoid that nagging thought that there must be an easier way to get a faster pick-up....or at least a way that doesn't involve making the stressed components smaller.........
Well Colin - in the mountain bike word there is .. in recent times getting a faster pick-up became an obsession with the manufacturers .. and we have seen "click wars" with vendors jousting with one another for maximum "clickage" !!! .........
If those Novatec and Shimano hubs are "easier" then I must be a Dutchman!
A lot of it is "old news"
Drive side bearing under the spoke flange; worse than screw-on blocks.
Double-decker pawls with a tiny bit hanging on by their fingernails? see the very first post on this thread.
3 pawls engaged? seen it on tandem blocks, years ago.
The Novatec ratchet ring is probably bigger than in a screw-on block
It'll all work fine when its new, clean, and not under stress.
Full of muck with a bit of wear and a bit of flex, I'm less certain.
The Shimano one seems to have a quickthread from the freehub body pulling the freewheel into engagement, so the spring is (like a pawl spring) "just for starters".
Theres a thread here viewtopic.php?f=5&t=145173&p=1597631#p1597631 where somebody got excellent service from some cassette bearing hubs ....but it turns out they are Hope hubs, and somebody said Hope design their own cassette bearings, and get them made. ....which is a bit different to using cassette bearings designed for high speed, low load, clean, dry, indoor use.

My £5 says you can't get 10 years use out of them. :wink:
markjohnobrien
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Re: Shimano freehub body internals

Post by markjohnobrien »

531colin wrote: 22 Apr 2021, 9:01am
zenitb wrote: 20 Apr 2021, 10:50pm
531colin wrote: 19 Apr 2021, 10:29am I can't avoid that nagging thought that there must be an easier way to get a faster pick-up....or at least a way that doesn't involve making the stressed components smaller.........
Well Colin - in the mountain bike word there is .. in recent times getting a faster pick-up became an obsession with the manufacturers .. and we have seen "click wars" with vendors jousting with one another for maximum "clickage" !!! .........
If those Novatec and Shimano hubs are "easier" then I must be a Dutchman!
A lot of it is "old news"
Drive side bearing under the spoke flange; worse than screw-on blocks.
Double-decker pawls with a tiny bit hanging on by their fingernails? see the very first post on this thread.
3 pawls engaged? seen it on tandem blocks, years ago.
The Novatec ratchet ring is probably bigger than in a screw-on block
It'll all work fine when its new, clean, and not under stress.
Full of muck with a bit of wear and a bit of flex, I'm less certain.
The Shimano one seems to have a quickthread from the freehub body pulling the freewheel into engagement, so the spring is (like a pawl spring) "just for starters".
Theres a thread here viewtopic.php?f=5&t=145173&p=1597631#p1597631 where somebody got excellent service from some cassette bearing hubs ....but it turns out they are Hope hubs, and somebody said Hope design their own cassette bearings, and get them made. ....which is a bit different to using cassette bearings designed for high speed, low load, clean, dry, indoor use.

My £5 says you can't get 10 years use out of them. :wink:
Yes, Hope bearings are not the average, run of the mill, but are custom made by a specialist manufacturer.
Raleigh Randonneur 708 (Magura hydraulic brakes); Blue Raleigh Randonneur 708 dynamo; Pearson Compass 631 tourer; Dawes One Down 631 dynamo winter bike;Raleigh Travelogue 708 tourer dynamo; Kona Sutra; Trek 920 disc Sram Force.
zenitb
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Re: Shimano freehub body internals

Post by zenitb »

531colin wrote: 22 Apr 2021, 9:01am
zenitb wrote: 20 Apr 2021, 10:50pm
531colin wrote: 19 Apr 2021, 10:29am I can't avoid that nagging thought that there must be an easier way to get a faster pick-up....or at least a way that doesn't involve making the stressed components smaller.........
Well Colin - in the mountain bike word there is .. in recent times getting a faster pick-up became an obsession with the manufacturers .. and we have seen "click wars" with vendors jousting with one another for maximum "clickage" !!! .........
If those Novatec and Shimano hubs are "easier" then I must be a Dutchman!
.......
.......

My £5 says you can't get 10 years use out of them. :wink:
LOL !!! Just in case your bank manager is fretting about the potential liablility of your £5 bet coming due in 10 years time Colin here are some photos of those pawls in action ... (not my photos BTW)
Novatec D642 cracked pawls !!!
Novatec D642 cracked pawls !!!
From https://www.mtbr.com/threads/hightower- ... g.1064376/

In the Chain Reaction reviews of this hub it looked like many users of the Nukeproof Horizon (same hub badged) had this problem.
Example user feedback ...
Example user feedback ...
https://www.chainreactioncycles.com/nuk ... lsrc=aw.ds

I am assuming either the casting or the hardening of these pawls is suspect. I guess this is the reason we try to stick to tried and tested hub designs !!!

Looks like your cash is safe in any event :-)
hoogerbooger
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Re: Shimano freehub body internals

Post by hoogerbooger »

RE lubricating a Shimano freehub, I see Brucey said there is enough room between the dust seal and lockring/cup ......to add LandRover swivel SFG.

I know there are differing views and a camp that remove the LH seal to add.....but I presume there is some risk of damaging the seal doing this.. ..

So if I want to carry on using No 2 grease in the hub bearings ....should this routine adequately lubricate yhe freehub:

1) remove axle & clean out old grease.
2) syringe in some SFG to ball race
3) stand wheel vertically
4) turm freehub outer to hopefully draw in SFG to internals
5) spin wheel holding freehub every now and again
6) Perhaps leave standing vertical over night.
7) clean out surplus SFG and grease with No 2 and replace axle/hb bearings.
6.5) SFG/oil the LH side of the freehub before replacing axle to help ensure LH seal is wetted.

?? Views?

I saw one comment somewhere that there was some risk that the SFG and No2 might might mix ending up with something thicker getting into the free hub with risk to pawls sticking ? Any views ?.....sounds a bit theoretical to me and not likely?
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slowster
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Re: Shimano freehub body internals

Post by slowster »

I would check whether the freehub has a seal on the left hand side, which I expect it will have unless its an old model (either check the Shimano tech doc online for the hub model, or remove the freehub from the hubshell and examine it). If it has a seal, I would lubricate the freehub with gear oil. If you remove the freehub body, I found it quite straightforward to remove the seal with a pick and introduce the gear oil from the LH side, otherwise add the gear oil from the outboard side as per Brucey's instructions. Before doing that I would check whether there is any play in the freehub, and if necessary fix that before adding the gear oil (hence presumably Brucey's advice to run new hubs in and see if freehub play develops before properly setting up the hub/freehub and lubricating it).
hoogerbooger
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Re: Shimano freehub body internals

Post by hoogerbooger »

Noted.

I have EP 90. But if I use oil isn't it more likely to mix with the No 2 grease on the hub bearings......or is it about getting the amout you add right.

(It's the freehub on a deore lx fh-t670. Has LH seal. Has done circa 5000 miles on original grease in mostly dry weather. Shimano grease was remarkably clean..now removed. All race tracks fine. There is the a very small amount of play.....but as I don't have the tool I was not going to try removing shims. I think I would need to have a spare correct replacement freehub in the bunker before I attempt shim adjustment.)
old fangled
slowster
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Re: Shimano freehub body internals

Post by slowster »

hoogerbooger wrote: 14 Jun 2022, 1:08pm I have EP 90. But if I use oil isn't it more likely to mix with the No 2 grease on the hub bearings......or is it about getting the amout you add right.
I just followed Brucey's instructions in his various posts on the subject (viewtopic.php?p=1564606#p1564606). Because I already had the freehub body off, I removed the seal and with the LH/inboard side uppermost I added gear oil to the bearings until it started to appear on/leak from the other side of the freehub. The Landrover SFG that I then used to grease the bearings oozed out a bit after a while past the hub seal on the non-drive side, which I just wiped off when I noticed it, but has not done so noticeably on the drive side, despite my having flooded the freehub with gear oil.
hoogerbooger wrote: 14 Jun 2022, 1:08pm There is the a very small amount of play.....but as I don't have the tool I was not going to try removing shims. I think I would need to have a spare correct replacement freehub in the bunker before I attempt shim adjustment.)
When I set up my two hubs, I could feel ~1mm of play in the freehub of one when holding the largest sprocket, and I figured that might make a significant difference to the life of the freehub, so I decided it was worth attempting to adjust the shimming.

Based on Brucey's posts I think the biggest risk when doing so is of damaging the RH seal, i.e. deforming it so much when removing it that it will not seat satisfactorily inside the freehub when re-assembled*. The seals are available separately, and the freehubs are in stock at SJS, and I would not worry about buying either in advance as a precaution if you did decide to attempt it.

https://www.sjscycles.co.uk/hub-spares/ ... y3cr08000/

https://www.sjscycles.co.uk/hub-spares/ ... y3d698040/

* Brucey recommended tapping the seal inwards to dislodge it enough to allow it to be removed. That worked for me and the seal was not deformed, and I was able to reuse it. If the seal is levered out (one of the methods shown in the video below), I think there is a much higher risk of it being damaged and needing to be replaced.

https://www.youtube.com/watch?v=X9gIEG1db0s

It's still early days, but both of the hubs I have lubricated thus are running well, and the silence of the freehubs when freewheeling suggests that the oil is effective.
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531colin
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Re: Shimano freehub body internals

Post by 531colin »

Since 2018 my annual maintenance is....
remove cassette
back off L. cone enough to get sight of the hub bearings.
Squirt some fresh grease into the L bearing
Push the axle through to get sight of the right bearing
Squirt some fresh SFG into the R bearing
Re-adjust the bearing. (slight play which disappears when Q/R done up....or use hub vise)
It seems that enough lubricant gets into the freewheel mechanism.
hoogerbooger
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Re: Shimano freehub body internals

Post by hoogerbooger »

I am presuming that the SFG doesn't migrate along the axle to the LH bearing ? ....or it is not an a problem if it does?

I presume the only reason that you use No 2 grease on the LH side (IIUC) is that without a grease nipple it's practically difficult to top up SFG on both sides ....especially with the Sunday Best on.

(I've ordered the tool for the freehub lock ring/cup....and I will practice with the shims on an old parallax hub)

[Edit 0.5mm play at 32 tooth cassette sprocket]
old fangled
slowster
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Re: Shimano freehub body internals

Post by slowster »

hoogerbooger wrote: 14 Jun 2022, 6:26pm I presume the only reason that you use No 2 grease on the LH side (IIUC) is that without a grease nipple it's practically difficult to top up SFG on both sides ....especially with the Sunday Best on.
The reason for not using SFG on the NDS is that there is a risk that any grease that leaks past the hub seal will contaminate a disc and disc brake pads, i.e. use SFG on both sides of the hub if it is a rim braked wheel. As far as ease and cleanliness of application of SFG is concerned, I would use a cheap plastic syringe or a grease gun.

I suggest you read this post of Brucey's regarding shim removal - viewtopic.php?p=1062878#p1062878.

NB Don't lift or tilt the outer main part of the freehub body even slightly once the cone is loosened more than a turn or so, that will keep the lower/inboard freehub bearings in place. I learned that lesson the hard way - viewtopic.php?p=1644598#p1644598
Jamesh
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Re: Shimano freehub body internals

Post by Jamesh »

Must say I do miss Brucey's knowledge on such subjects
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