Slash5

I've rebuilt lots of hubs, headsets and bottom brackets but lately have been wondering, how much grease do you use?
I always mostly fill the cup with a good layer of grease and insert the bearings. Then put a good layer of grease on top. Then a light layer of grease on the cone/spindle. When I assemble, grease oozes out and I clean it off.
I've noticed though that when I disassemble bearings, assuming they have any grease, it's usually just a thin skim in the cups and the bearings are more or less just oily.
I assume the bearing probably only needs a bit of grease to function correctly. Am I doing it wrong or is this just a case of grease costs money so shops don't use more than needed?

fietsbob

In Manufacturing a Million Hubs a Company lowers the cost of grease over the whole production Run.

by figuring out how Little is adequate ,

But as the Owner of the bike you may have a contradictory idea of what Adequate Is

and since you are only dealing with Your bike May choose to add More ..



Rarely does the Mechanic doing the set Up of a new Bike from the Import shipping carton to the sales Floor

Open Up the hubs and add grease , so you are seeing a Factory component Manufacturer's decision,
Not the retail Shop's Choice.

For your Overhaul You are free to make your own choice as to the meaning of 'Adequate'.

Crankycrank

This would be the correct method IMO. Always better to have too much and just wipe off what oozes out. The hub spits out what it doesn't need but won't tell you until it's too late if it's not enough.

Tim_Iowa

[QUOTE=Slash5;18509541
I always mostly fill the cup with a good layer of grease and insert the bearings. Then put a good layer of grease on top. Then a light layer of grease on the cone/spindle. When I assemble, grease oozes out and I clean it off.[/QUOTE]

That's how I do it. A generous amount of grease in the cups to hold the balls in, and some oozes out when closed.

bradtx

Slash5, When I overhauled my mega mile touring bike to use as my beater bike, I wondered the same thing. There was so little grease in both hubs, but no damage to the races, cones, or bearings. Anyway I overhauled them the same as you...same with the headset. In my own foggy logic, the extra grease, while it won't make anything water proof, may make them a little water resistant.

Brad

corrado33

Technically you only need as much grease is necessary to lubricate the races/bearings. However I just load it up to prevent water incursion. Less grease would also produce more free spinning bearings.

Phloom

I slop in as much grease as I can. It's messy and my wheels don't spin as freely as they could. But better too much than too little.

Bike tinker man

The standard engineering philosophy on packing bearings is to pack the bearing cavity / space to about a 1/3 full, but this applies on higher speeds to stop overheating, but on a bike wheel etc, I agree with corrado33 "to prevent water incursion" so there is no need to make a complete mess of it so its everywhere, so pack it but allow the grease to move around also.

rydabent

Pack the bearing clear full. Any that oozes out can be wiped off and serves to keep dirt and water out the the bearing. Why leave space for dirt and water to get in?

CliffordK

I'm also of the as much grease as will go in camp.

However, grease beyond the cup along the length of the axle will do absolutely nothing. So, fill the cups, don't fill the space to the inside of the cups.

Andrew R Stewart 

With enough grease so that some gets squeezed out on assembly the balls will determine their "correct" amount. As the balls rotate around the cone/cup they plow a path through the grease, pushing aside any more then the bearing will accept. This extra will surround the bearing and both limit contamination and feed fresh lube to the bearing over time and lube wear. Andy.

pdlamb

I was with you until you greased the cone and spindle. I figure the grease on the cone will be squeezed out by the grease on top of the bearings, and there's just too much volume inside the hub to fill.

A bit on the outside of the cone might be good as a rust preventative, though.

jsjcat

I've never seen bearings fail from too much grease!

corrado33

You would think so, but it's not true. All it does is attract dirt and grime. (Fair enough, it probably won't RUST, but it'll still get dirty and gritty.) Same wisdom for wiping the lube off of the outside of your chain.