Grease Guns, lube ports and grease nipples

For discussions about bikes and equipment.
Brucey
Posts: 35161
Joined: 4 Jan 2012, 6:25pm

Re: Grease Guns, lube ports and grease nipples

Postby Brucey » 24 May 2018, 6:08pm

there are one or two types of grease that are not compatible with one another. The most common reaction is that the mixed grease turns more fluid than normal, which is a disaster in some machines, not so much in a bicycle hub; the grease just comes out faster than normal and you need to regrease sooner than you might have otherwise. A much less common reaction is that the grease thickens.

You would be extremely unlucky to have a small residue from one grease type in a grease gun cause such bad contamination that it causes problems. If in doubt, clean the reservoir, eg by scooping out the remaining grease using a plastic spatula (which you can make eg from a food container) and purge the gun out (i.e. until the new grease runs clean) before using it on anything.

The purgings need not go to waste; they can be kept in a small container and used as an assembly lube for nuts and bolts, pedal threads etc.

cheers
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mig
Posts: 2030
Joined: 19 Oct 2011, 9:39pm

Re: Grease Guns, lube ports and grease nipples

Postby mig » 21 Jun 2018, 10:33am

i always give the winter bike a good service sometime around this time of year. hence i use up plenty of grease and will be looking for more for the hubs in the main. how best do i ascertain if greases contain corrosion inhibitors? do descriptions of them contain the same coding/lettering somehow?

Brucey
Posts: 35161
Joined: 4 Jan 2012, 6:25pm

Re: Grease Guns, lube ports and grease nipples

Postby Brucey » 21 Jun 2018, 11:42am

look for greases that are meant for extreme service conditions; in truth these conditions most closely resemble those found on a bike; conditions in bicycle bearings more closely resemble (say) those in a crane slewing ring than in (say) a car wheel bearing. Often greases that are any good are made to meet an manufacturer-specific specification rather than a generic one.

Of commonly available greases Shell Gadus S2 V220AD

https://www.shell.com/promos/lubes/btb-products/gadus-product-range/_jcr_content.stream/1426853626868/7bcbd3210794a5848df8a13c616bf253f2868e0f30ba44b9c22358e18070274e/shell-gadus-brochure.pdf

is probably about as good as you will find, even though its specification is skewed towards high temperature, high speed use, which has (of course) stuff-all to do with conditions on bicycles. There are better greases available but they are so specialist in their applications that they are not widely supplied, so basically you can't easily (or at all) buy them in the UK.

Shell Gadus greases were formerly known as 'alvania' series greases and as this page explains

https://www.reference.com/science/equivalent-shell-alvania-grease-fb9e872730171764#

other manufacturers make similar greases. But as with many things, the devil is in the detail.

Doubtless you will find those who advocate the use of cheap greases that 'look the same'; for example you can buy 1lb of 'moly grease' for as little as £3 from some sources. It might work OK 90% of the time too, but it is the other 10% of the time that causes things to break and wear out, and that is what you need to concern yourself with.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~