timo888 

I needed to find a 7-speed hub for my folding bike and bought a NOS hub with WTB grease ports. What is recommended practice for re-greasing such a hub? I assume the grease needs to be flushed and replaced. What is the best way to flush the old grease? Soak the hub in mineral spirits for a few days and then inject mineral spirits into the port until what leaks out runs clear?

This article

https://www.bearingtips.com/shelf-li...gs-lubricants/

talks about the shelf-life of grease.

davidad

You pump grease into the wheel until clean grease comes out. I overhaul my shimano hubs every 2500 miles.

dsbrantjr

+1 Injecting mineral spirits may eventually get the old grease out but the remaining amount will break down the new grease.

Andrew R Stewart 

Ideal would be to pull off the bearing seals and flush out the old before refilling with fresh. Second is injecting solvent then air then fresh grease. What most will do is fine, just inject fresh periodically. These hubs and headsets are very nice parts. Andy

ThermionicScott 

What hub did you buy? Considering the age of the old grease (even if the hub is NOS as claimed), it would be worthwhile to completely take it apart and clean it, if possible.

Dave Mayer

I know we've got too much time on our hands, but some of us are way overthinking this. The grease inside the hub may be dried, but it isn't going to hurt anything. Mixing the old with new grease will not result in any harm. Worst case: that the insides of the hub is somehow contaminated and filled with plutonium dust, but inserting your grease injector and pumping away will remove at least 90% of it. Then take a spin around the block and wipe up the stuff that oozes out each side. That's not clean enough? Then repeat; now you're at 99% clean.

I decided to service my 80's Campagnolo hubs yesterday. I inserted my auto bearing grease injector into each port and spritzed away. After a few miles on the bike, the excess that oozed out was clean as new. There: I am done for another year.

My injector cost about $10. The auto wheel bearing grease tubes cost about $5 each and for last years. Or you can buy the exact same grease formulation at a bike shop and pay 3 times as much for a third of the volume.

RGMN

Grease Guard hubs are of a standard cone design with the outer dust shield replaced with a loose fitting grease seal, and a couple of additional grease seals on the inside to prevent grease from filling up the hub. They are just like any other cone style hub to disassemble and clean, just be careful when pulling the axle out to prevent damaging the internal seals. I would pull them apart and clean out the old grease rather than soaking the hub in solvent. With the solvent you risk damaging either the inner seal or outer seal, and I really don't think it will clean them out that well. If you don't want to take them apart just pump them full of grease until you get clean grease coming out. They will ooze a little grease out when you use them, just get used to wiping if off after a ride.


WTB had a special grease for them that contained Teflon. The Teflon prevented squeaking of the seals, particularly if you had a GG BB. As far as I know it is no longer available, the closest substitute is Finish Line Premium Grease with Teflon.