Nothing a good flush with GT85, blowdry with a compressor gun and regrease (with the right grease – or it will keep slipping) won’t sort. Very, very easy.
Undo tiny clamp screw on axle bearing tension adjuster
Loosen bearing tension adjuster (much easier to do in the bike – remember there is a “helper hole” in it as well as the adjuster bolt to put an Allen key in and use it for leverage.
Remove wheel from bike
Remove cassette
Remove disc rotor
Remove bearing tension adjuster (unscrew it off the axle)
Remove axle (pull it out from freehub side)
Grab freehub in your hand, yank outwards whilst turning slightly counter-clockwise (you won’t break it, don’t worry, just give it a good yank)
Using the little red straw on the end of the can, squirt GT85 liberally inside freehub body and wipe a rag through centre where the axle was (check the bearings are all ok)
Put freehub to one side to dry
Look inside the hub shell. If you put your fingers in you can see/move the drive rings apart by hand – they will spring back again. They are relatively delicate so don’t wrench them around. Squirt GT85 liberally down between the two drive rings all the way round the hub to flush out crap.
Either leave to dry or “encourage” with a compressor air gun if you have one.
Wipe inside everything with a dry, clean rag.
Check the hubshell bearings are smooth. If not, remove outer metal shield with a Stanley blade (there is a slit in it) and then carefully remove inner rubber seal (note if you are not careful it is possible to slice this whilst removing the outer shield. So be careful). Flush out bearings with GT85, regrease with good quality waterproof grease, then put the shields back on in the right order. The outer metal sheild can be a bit of a faff but it will snap back in eventually. Make sure it’s seated totally flat. It often takes a few goes.
Now to rebuild the hub – apply Chris King grease in between the drive rings inside the hubshell, to the bearings inside the freehub and to the freehub drive splines.
Shove the freehub back into the hub (a little clockwise rotation helps). It sort of clicks back in when it’s in far enough. It’s easy not to shove it in hard enough so check it’s all the way in. Make sure it drives the hub forwards and turns backwards ok.
Put the axle back in having greased the bearing conact surfaces and adjuster ring threads.
Screw adjuster ring back on
Put disc and cassette back on
Put wheel in bike
Adjust axle bearing adjuster until there is no play in bearings
Tighten axle bearing collar bolt (be very gentle – easy to strip).
