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Do you put copper grease (or something else) on a freehub directly before sliding the rear sprocket on? I put a light coating on by habit when fitting just because I don't like the idea of bare metal-on-metal, and copper grease seemed right by instinct. But that instinct is from bicycles whose engines prefer refined hydrocarbons to pie'n'mash. There was nothing or a very light oil when I took the old sprocket off, but it didn't come off that easily either.

Presumably you should also put something on the threads of the lockring; I actually forgot that, but I'm minded to put a little bit of copper grease in there too next time I take it off.

The sprocket (and the chain, and one spoke in the rear wheel...) are all new. (There's a chain stretch tool now hanging up next to the bike, so hopefully the next chain change won't involve replacing a spoke.)

This question recommends any old grease, but copper grease isn't a lubricant, so this strikes me as a separate question.

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Antiseize/copper grease is theoretically better, but plain old grease will work just fine. There’s no relative motion here, so lubricity is not a factor. All we are looking for is adding corrosion resistance to avoid sprockets being fused to the freehub body or the lockring getting stuck.

I personally use grease on the freehub body and antiseize on the lockring, but exclusively using either is equally good. I don’t want to have the mess that is an antiseize-covered freehub body.

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    I've read in some maintenace sections of cycling magazines not to use lubricant but I find it hard to seize (pun intended) as they never give an explanation. I use new grease after wiping away the old stuff at every removal of the cassette.
    – Carel
    Commented Nov 10, 2021 at 21:11
  • @Carel I imagine grossly excessive application may get flung onto the brakes or something. Might also attract dirt and stuff.
    – MaplePanda
    Commented Nov 10, 2021 at 21:36
  • I've also read that, with the same response. Ofc we're talking a thin coat here (like everywhere you use an antiseize).
    – 2e0byo
    Commented Nov 10, 2021 at 23:35
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    @MaplePanda: Exaggeration is bad wherever it happens, of course!
    – Carel
    Commented Nov 11, 2021 at 19:02
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Greasing the freehub body splines is good when it's prone to creaking for whatever reason, which is largely a problem specific to aluminum shallow-spline (as opposed to the deep splined FH-7800 and WH-7800) freehubs and their issues with getting notched up. The lubrication can mitigate the noise, but not the damage.

A coat of grease or antiseize is also reasonable in corrosion-prone environments, like salted roads or ocean air.

Antiseize is the messiest thing you could choose for either purpose, but will probably outperform grease were you to test. (It usually does in testing for basically everything but reducing friction and wear in bearings.)

Other than that, greasing freehub splines mostly is messy with little or no benefit. Steel freehubs can get some rust sometimes, but it's of no consequence outside of the above circumstances.

Lockring threads should always be lightly lubricated, but you also need to keep grit from sticking in that area. I usually do a small dot of grease. On bikes that I know get maintained with any regularity I do a few drops of oil flowed through the threads, rationale being that's well sufficient to prevent any actual problems and is also the neatest. If it's a titanium freehub body, use a small amount of antiseize applied very carefully, because you want to keep it out of the bearings.

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I think you are referring to copper antiseize, which is usually recommended to prevent galvanic corrosion with titanium bike parts. Generally, I would antiseize any interface where one of the parts is titanium.

Almost all freehub bodies are aluminum or steel. They're interfacing with aluminum cog spiders and steel cogs. (NB: Shimano and Campagnolo's top end cassettes have titanium largest cogs, but all these are mounted to aluminum spiders). Thus, you don't need copper antiseize here. I believe that antiseize is really grease with copper particles added, and if true then there's no harm in using it apart from it being unnecessary.

However, come to think of it, some titanium freehub bodies exist. White Industries and some older Shimano Dura Ace and XTR FH bodies are titanium. I have had a White Industries rear hub for a couple of years and I haven't noticed any problems with seizing. In theory, antiseize would not be a waste here, however.

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  • XTR M980 and M9000 use titanium freehub bodies. Not sure about the road side, but I think they do too.
    – MaplePanda
    Commented Nov 10, 2021 at 21:38
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    @MaplePanda I forgot about the MTB side. Dura Ace is the equivalent, and many DA freehubs were titanium. I am not sure if this applies to the 9200 series wheels, but I am thinking those should be aluminum. Ti is pretty expensive. It does enable you to run shallow splined cassettes (e.g. Shimano) without gouging, but you could just make the splines deeper and more numerous (e.g. Campagnolo, Shimano Microspline, whatever name Shimano is giving to their new 12s DA hub bodies)
    – Weiwen Ng
    Commented Nov 10, 2021 at 21:42
  • sadly I'm nowhere near titanium. This is an old steel road bike frame, with low-end shimano fittings and decent modern (alloy?) weels, but no advanced metullurgy...
    – 2e0byo
    Commented Nov 10, 2021 at 23:33
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You're right - copper grease/assembly compound is not a lubricant. But threads generally don't move once assembled+torqued, so don't need lubricant anyway. Having something to stop them seizing together is a different purpose than lube, though grease can do both tasks.

Personally I use copper clay on all threads, grease in bearings, and light oils on pivots.

The only people who would use less would be pro racers who would use oil, or nothing, for ultimate lightness in races.

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