Grease - When, Where (and What) to use?

[Falco]

I have been doing a bit of reading, prior to removing the front caliper on my CG. I found the pad pins to be very stiff to turn on my first attempt (though turn they did), so I went looking for information about how to grease them.

The result of this is a lot of conflicting information.
I have seen opinions that run the gamut from "never put any grease near the calipers, especially copper grease and especially on the back of the pads because the grease will make its way down the pistons and cause the rubber boots to swell up" all the way to "I grease every fastener on my bike and never had a problem ".

So my question is: What grease should be used and where?

There are plenty of bolts I don't want to seize but I also don't want to slap copper grease on everything and hope for the best. For example can I use it on my pad pins? Or the spark plug? Are there any general rules about what type of grease to use (copper/lithium/silicon/red rubber) for what applications?

[NJD]

I made a similar thread. Some answers on their to read through.

[Islander]

Anti seize grease (copper grease) on the pins and the back of the pads - just a smear, not too much.

Red rubber grease for seals and pistons, and if it's a sliding caliper then use this or a silicon grease (rubber friendly) on the sliding pins under the rubber boots.

[Falco]

I do wish the search function worked for me. All I get for every search attempt is:

https://i68.tinypic.com/2s1ah35.jpg

Many thanks NJD and Islander, I'll read the already extant thread.

[NJD]

[Hong Kong Phooey]

[Falco]

[NJD]

[Falco]

[Matt B]

The plug socket that comes in the Bandit toolkit has the rubber insert to grip the plug. I have no choice but to use it because my proper plug sockets are too fat to fit in there.

Going back to the grease thing - copper grease is fine to use on the back of pads. People who say differently are just plain wrong. Use a smear on the back of the pads where they contact the pistons. Next time you have your pads out take a look and you will see it actually thickens and hardens over time, doesn't melt. No danger of it getting onto the rotors.
____________________
stinkwheel: He had an animated .gif of a cat performing fellatio. It's not socially acceptable. It can have real life adverse effects on other people.

[NJD]

[stevo as b4]

I always use copper grease on spark plug threads and any bolt or nut that's not plastic anywhere on the bike. A smear of copper grease on a spark plug won't hurt at all.

You shouldn't be fitting spark plugs if you need a torque chart or wrench to do the job. Common sense and experience is all that's required. If a tiny bit of copper got into the combustion chamber (another scare story myth) it won't make your engine blow up or wear out in 5miles as some say.

I use the wrong grease technically for lots off applications, like for example copper grease on battery terminals etc. But people can get far too anal about what to use for every little Job and think they need dozens of different products because it says in the book etc.

[spottedtango]

See if you're skint and because red rubber grease is based on vegetable oil. Could you not just use veg oil for lubing up brake caliper pistons?

[Rogerborg]

I've always lightly copper-greased plug threads, and prefer to under- rather than over-tighten them.

The inconvenience of having to remove/replace or re-tighten slightly is far less than a 40+ page "plug snapped what do?" thread.
____________________
Biking is 1/20th as dangerous as horse riding.
GONE: HN125-8, LF-250B, GPz 305, GPZ 500S, Burgman 400 // RIDING: F650GS (800 twin), Royal Enfield Bullet Electra 500 AVL, Ninja 250R because racebike

[stevo as b4]

It's personal preference alot of the time too. Take brake caliper pistons as an example.

Some people smear the seals and piston in clean brake fluid, some use rubber grease, silicone grease and even silicone spray.

You can use vaseline, lithium grease, copper grease, dielectric grease or molybdenum grease on battery terminals, it's not a critical application or requirement.

In a CV joint, wheel bearing, or something like an underwater marine gearbox housing, you need to use a more appropriate product to deal with the requirements, and have the properties required for dealing with more extreme applications.

It's the same deal with gasket compounds and applications too. Some people join crankcases with blue holomar, others use threebond, RTV or even bathroom silicone sealant. There's a right and wrong product for some applications, but a whole load of situations where people use their own ideas and methods for sealing and lubing things.

[NJD]

So in my book of notes I have copper grease as one that you use on bolts that you may want to remove in the future. So, copper grease on the oil sump plug also?

[stevo as b4]

It probably won't be likely to seize due to its constant immersion in oil at the end of the thread. Stopping leaks is a bigger problem for many than worrying about trying to undo the drain plug come service time IMO.

[Matt B]

[Nobby the Bastard]

[P.addy]

Turn off adblocker for bcf. Search will work.

[Falco]

Out of interest does adding grease to a bolt change the torque setting at all? I know that most torque settings are given for lightly oiled bolts, would the change for grease (of whatever type) be negligible?

[Kickstart]

Hi

I use copper grease on plugs, and on most other bolts. Makes life a lot easier when you have to undo the item at some point in the future (and as I hate selling things, that could be a decade or more later).

I avoid using copper grease on anything that is going in to an oil bearing part of the bike. Don't really want the copper floating around in the oil.

I have heard of claims that copper grease should not be used on plugs for vehicles with catalytic converters. Not sure if this is true, or just one of those scare stories.

On a sump plug I wouldn't use it. They tend to be a pretty coarse thread, are not very long and have plenty of oil lubing the thread anyway.

[stevo as b4]

As Katy said torque settings can change alot if you lubricate a thread before tightening a fastener.

For some applications it's critical, but for many it's not. Experience and common sense tell far more than torque settings for assembly of many components. Even installing a cylinder head on a car engine with say 10bolts or studs, I'd put everything on finger tight first or using an extension bar with no breaker bar or wrench. Then I'd give everything probably 1/2 a turn in sequence, before only then looking at the full torque setting figures and setting my torque wrench to suit.

On loads of mechanical assemblies you don't need a torque setting at all, other than sense. The problem with people that don't know what they are doing but think they can follow a manual or set of figures, is that they have no experience or common sense regarding how tight things should be and they break things then. I'd never expect anyone to follow or use a torque setting on a wrench to fit a car wheel, but people that have never done it and thing a book can show them everything will try to measure everything and apply exact figures.

Some critical fasteners will specify that you torque them up dry, while others will tell you to lubricate a thread before tightening them to get the correct figures. Big end cap bolts or flywheel/clutch hubs are maybe one such example where there's an exact specific figure to achieve. A thermostat housing bolt or inlet manifold bolt less so.

Putting the manual down and using experience and feel for many things is often the right and best way to proceed IMO.

[Rogerborg]

Last time I had the cam cover off on Mrs Borg's mummy bus, I fitted a new gasket, carefully cleaned the faces and the threads, lubed the bolts with 5W30 and torqued them down exactly to the specified (wet) settings, checked with both a clicky- and a deflection-wrench.

It felt like it wasn't enough, and it leaked like a sieve.

My working hypothesis is that the specified settings are safe limits for not snapping the bolts rather than for actually securing the cover, and that they fully expect mechanics to torque to that and then give the bolts another quarter or half turn for luck.

Which is what I did and it's been fine since.
____________________
Biking is 1/20th as dangerous as horse riding.
GONE: HN125-8, LF-250B, GPz 305, GPZ 500S, Burgman 400 // RIDING: F650GS (800 twin), Royal Enfield Bullet Electra 500 AVL, Ninja 250R because racebike

[Hong Kong Phooey]