# Shimano freewheel lubrication



## Pieter (Oct 17, 2005)

Please advise me about a Shimano 105 freehub with some 18kmiles.

Following many miles plus a long wet ride, I repacked the hub bearings, so removed the freewheel. I removed the seal and found wet grease emulsion. I flushed the entire unit with light petroleum spirit, and attempted to relube.

I used grease dissolved in petroleum, then heated the unit. While this should be OK for the pawls, the ball bearings still sounded dry and could be rattled around. I pushed in some grease from the seal end, but the cone bearing end was still rattling. Pushing in more grease from that end cured the rattles - it appears that there is some grease over all the balls.

The freewheel still has some roughness. Do I just accept this on an 18k miler and run it, or attempt to disassemble and grease properly? I have heard about a special lubricator - how does it work?


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## FBinNY (Jan 24, 2009)

Freehubs require 2 different lubricants. The ball bearings require grease, though on the designs where the bearings support the freehub only and not the wheel a thick adhesive oil is OK. 

The ratchet assembly needs oil thick or adhesive enough not to spin out, or *very light* grease. Grease in the ratchet area could cause two problems. It might be too thick and overpower the pawl springs causing freewheeling in both directions, and/or it builds up in the ratchet ring not allowing the pawls to pocket fully, causing dangerous slippage under high torque (often chipping the pawls or ring).

The problem with the freehub lubing gadgets is that they don't segregate the two areas, so unless you decide to use oil for both, I'd pass on the device and do a proper job, dis-assembling and lubing the old fashioned way.


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## MR_GRUMPY (Aug 21, 2002)

Unless you were riding in two feet of water, the freehub shouldn't need lube. In all my years of riding, I have never lubed a freehub. Shimano hub bearings are pretty well sealed. I've got wheels that are 10 years old that have never been touched.


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## Roadplay (Jan 2, 2007)

I recently changed bearings on a set on my wheels, the instructions said to use a light 20/30W motor oil on the ratchet assembly after cleaning.


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## Pieter (Oct 17, 2005)

Thanks. 

Maybe I should try making a tool for unscrewing the inner cover of the unit and see if disassembly works out.

The unit has been making the odd mis-engagement lately, so I suppose real inspection and lubrication is in order.


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## Pieter (Oct 17, 2005)

MR_GRUMPY said:


> Unless you were riding in two feet of water, the freehub shouldn't need lube. In all my years of riding, I have never lubed a freehub. Shimano hub bearings are pretty well sealed. I've got wheels that are 10 years old that have never been touched.



The funny thing is - one hour riding in heavy rain and half inch deep water, had a grease-water emulsion oozing out of the hub seals. Clearly, water gets into this specific hub pretty quickly. Maybe the front wheel throws water right onto the rear hub?

And the freewheel's left side bearing (next to the seal) was waterlogged too.


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## nepbug (Jun 6, 2006)

Good luck if you go with the disassembly, Shimanos aren't really that serviceable. You might want to consider a Freehub Buddy by Morningstar Tools:
www.morningstartools.com/freehub_buddy1.html


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## Cleaner (Jun 19, 2009)

*Here is a guide for teardown/rebuild*

I have done this myself on an XTR freehub and it did need it, it was skipping. I do have the tool to remove the bearing race but you can make your own or may be able to buy one not made by Shimano.

http://www.icebike.org/Equipment/freehub.htm


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## DieselDan (Sep 14, 2002)

There is usually no difference in cost from changing out the freehub then servicing it. The cost savings of servicing is offset by the lower labor cost of replacing.


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## Pieter (Oct 17, 2005)

Thanks for all the info. I will look into a teardown, once I get to find or make a freehub disassembly tool.

The freehub buddy is an interesting device but is surely not available easily in this part of the world.

Simply changing the freehub is not that cheap here - and not much fun or challenge either ;-)


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## MattSoutherden (Jun 24, 2009)

FBinNY said:


> It might be too thick and overpower the pawl springs causing freewheeling in both directions, and/or it builds up in the ratchet ring not allowing the pawls to pocket fully, causing dangerous slippage under high torque (often chipping the pawls or ring).


Don't worry too much about the pawls. It's your plums you should be worried about if the ratchet slips when you stamp on the pedals!


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## DieselDan (Sep 14, 2002)

Pieter said:


> Simply changing the freehub is not that cheap here - and not much fun or challenge either ;-)


Then you are doing it wrong.


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## Pieter (Oct 17, 2005)

DieselDan said:


> Then you are doing it wrong.



OK - here's my 2 cents worth based on actual hands-on experience FWIW.

Shimano discourages messing with freewheel units, and discontinued the special tool. 

I made a new one, essentially a big screwdriver : a 29mm wide blade of 3mm steel embedded in a slotted and machined heavy PVC cylinder.

If you can get the dust cap out undamaged, you are on. Like in my case, a year 2000 105 hub with very loose fitting dust cap. Disassembly and reassembly was not hard, and clearly a superior option to just flushing. 


However, a second (Ultegra) hub freewheel was clearly not going to give up its dust cap wihout force and resulting major distortion. 
The options in such a case are 
1) a Morningstar replacement cap, 
2) a cap from a scrapped freewheel (check among your MTB buddies and their LBS, cut / break the shell to get the cap out ),
3) machine a replacement from plastic or even aluminum.

So I partly concede - somewhat of a PITA. But it can be viable to DIY this one.


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## nepbug (Jun 6, 2006)

Pieter said:


> OK - here's my 2 cents worth based on actual hands-on experience FWIW.
> 
> Shimano discourages messing with freewheel units, and discontinued the special tool.
> 
> ...


Pictures of the tool you made and of the disassembled freehub?

Nice job.


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## Pieter (Oct 17, 2005)

*Photos*

Photos of disassembled, and partly assembled freewheel,
plus plastic / steel cup removal tool


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## mattotoole (Jan 3, 2008)

Shimano ratchet bodies do get wet and dirty but will run that way for years with no trouble. Flushing and relubing is worthwhile however as it ensures no problems and quiets them down.

You don't need to take them apart or use special tools. If the dust caps come out easily then great, it will be easier to flush the unit. But if they don't, just leave them in and flush as well as you can. Use a spray solvent like brake cleaner or soak the whole thing in parts cleaner. Let it dry throroughly, then relube with Phil Wood oil, which has plasticizers in it to keep it in place. Don't use grease or you're asking for trouble. Do use grease in the axle bearings though.

Doing this every year or so has kept my freehubs running smoothly and quietly forever. You'll notice the noise difference!

Traditional Shimano hubs (cup and cone, no cartridge bearings) really are the best. Nothing is as smooth, quiet or reliable over the long haul. If you have a problem just tear them apart with normal tools, clean and relube and be on your way. Currently I'm suffering with a noisy and clunky Rolf/Hugi rear hub. When those wheels wear out my next ones will have Ultegras or whatever for sure.


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