Not sure of bikes but as I guess you know a grease is basically oil held in a base compound, these are many and varied to cope with load, speed, temperature (high or low) corrosion etc and probably combination of several of these conditions. Common base would be a soap such as lithium, more extreme conditions probably a synthetic one.

Bill D.

Lithim soaps seems to be very good allround performers. It handles heavy loads and high temperatures, but it’s real strength lies in the adhesion and water resistance. It stays put even if exposed to water.

Hi, there isn’t a one type fits all bearing grease, just about everything associated with the bearing in use needs to be considered.

https://www.skf.com/uk/products/lubrication-management/lubricants

The above link will give you a lot of information, and this catalogue link below should help with a lot of your queries.

https://cdn.skfmediahub.skf.com/api/public/094fe398236d3d0a/pdf_preview_medium/094fe398236d3d0a_pdf_preview_medium.pdf#cid-595611

Regards Nick.

P.S. I have no association to the company in the above links.

When I worked for an industrial jacking company the grease department was the largest section of the stores.

The range of greases and compounds was truly mind blowing with even a very special section for jacking equipment to be used in nuclear plants.  We had one guy whose sole job was to ensure the grease store was properly controlled with regard to expiry dates and all the relevant certification was provided.

I now know a lot more about grease than I did this morning. My conclusions are look for Synthetic grease; don’t mix grease; additives like Moly are never a bad think to have for metal/moving parts. Lithium seems to be more to do with the grease staying in place than lubrication.

My expert in this field is away till next weekend but I will ask BUT it will be an in depth answer ! Leave it with me ! Noel.

Back to the OP’s original question… ‘Normal’ grease is, in fact, lithium grease: it’s by far the commonest type. Sodium-soap-based grease is very rare and has, as far as I know, no properties useful to us. Calcium-soap-based greases have better water-resistance than Li grease, which is poor.

As has been said, ‘grease’ now covers an alarming multitude of formulations – quite beyond a mortal’s ken. ‘Channelling’ greases are now popular, formulated to squeeze out of the way of balls and rollers in bearings, to reduce grease churning and heat production. I think they get this property from their fillers (of which there’s a bewildering choice). These behave differently from the softer greases of old, and I’m frustrated by not being able to find equivalents (at least in NZ). The NLGI classification relates to something like viscosity, but there’s far more to a grease’s characteristics than NLGI1, NLGI2, etc, despite what the retailer would have you believe…

Decades ago, Castrol LM grease (a good, multi-purpose Li grease) was a soft, translucent formulation. It tended to separate fairly readily, so there was a thin oil layer on top of the grease in the tin. Whatever happened to it? Now, a ‘multi-purpose’ grease seems to be a thick, sticky, opaque mess, with a higher filler content, presumably with marked ‘chanelling’ properties. It doesn’t separate out in the tin so readily, but, if left in a grease gun with a spring-pressurised resevoir, the oil dribbles out, eventually leaving a very stiff cake in the resevoir, which is the devil to clean (been there…).

My belief is that ‘chanelling’ greases are not good in slow-moving plain or sliding bearings, for which the ‘softer’ greases were OK. Can someone enlighten?

This sliding factor is important, bearings that are too lightly loaded can do this and it is most undesirable, in essence oversize bearings can be a problem just as much as undersize.

The thing to remember is this type of bearing, commonly called anti friction bearings or rolling bearings, work by rolling. This not to be confused with Roller bearings. Overgreasing can also cause problems by excessive churning creating high temperatures.

I reiterate that I am not a bearing expert, just many years experience of using bearings in highly loaded high speed conditions

Bill D.

Since we have come to the issue of bearings –  For electric motors Suffix C3 is a bearing with a clearance that allow hot running, if you are re bearing an electric motor C3 is the one to use !   Noel

I do now agree there is significant doubt over generic application of ‘black moly’

As it happens, I almost ran out of Castrol LM over weekend so had decided to get a replacement. I checked out Project Farm and concluded that I should get Red Line CV-2 red moly… which is good for bearings… and I made the wrong conclusion ‘moly’ is always good. I now realise I don’t know what red moly is and that it is probably different from black moly (MoS2). This is a synthetic, calcium grease so I also now know to remove old grease before applying.

Also, as it happens, I have a selection of HAGEN Automation micronised solid lubricants (tungsten WS2, moly, boron-nitride, PTFE) which I will now not be usingin combination with oil lubes for high speed bearings. So far I have been dusting it on things where I don’t want liquid or grease lubricants that might take up dust, dirt e.g. folding pocket knife. Red hot I tend to use graphite. I might add them to red line CV-2 for non-ball-bearing applications like angle grinder gears.