nahh

hey--

As half of a 'take it apart just cause' and half a 'take care of my bike' sort of thing i'm planning on taking off the freewheel on my bike.

so i got it taken apart till I hit a stag with taking off the actual freewheel. but whatever, went to my LBS and got the tool for the job...

as far as taking it apart, lubeing it up, and putting it back together is there anything i need to look out for?

so...thought i should ask before i make a mistake.
~thanks!

sch

Taking apart a freewheel is one thing, putting it back together another. Not quite
as complex as a shimano brifter, it is basically a LOT of very small ball bearings and
2 or 3 spring loaded pawls that engage a toothed ring. The problem is that grease
inside a freewheel is not a great idea so keeping the balls in place is not straight
forward but retracting the pawls so you can put the thing back together is also
not straight forward. It can be done but the art is largely lost. Freewheels are
cheap enough even now with inflated parts pricing that doing this once for interest
is useful but not with the intent of reuse of the freewheel. Some freewheels are
more approachable than others, but I did not pursue this after the first one I
took apart in the '70s 'exploded' losing enough of its innards I did not go further.

HillRider

The general consensus is freewheels are replaced, not serviced. You can lube them effectively by dribbling light oil into the seam between the stationary core and the rotating body around it and that should be sufficient.

For most freewheels, if you insist on disassembling them, the outer ring is removed with a pin spanner and is left-hand threaded. There are usually a couple of very thin shims and, as mentioned, LOTS of tiny beraing balls and springs. Have fun but have a replacement lined up first.

CrankyFranky

Hey - that's the way we learn!

See saint Sheldon's page https://www.sheldonbrown.com/freewheels.html as a start. This should answer most of your questions. Also, see the thread from yesterday titled "Wobbly Cassette.

Disassembly of the fw in not too hard.

BUT you're committed to getting the thing back together after a few dozen balls have run in all directions and two or three pawls may have jumped out... reassembly of the freewheel is only easy if you have the tools and the experience and plenty of time and a clean work area. And you have to know the tricks, otherwise you end up with a pile of tiny and now useless parts. If you forget one or put it back together wrong, it won't work.

Often, the only reason I would have for taking off a freewheel (not freehub) is that I need to get in to service and clean the axle bearings on that side, and then only if there's grit in the axle bearing.

If the axle is clean and doesn't demand your removing the fw from the wheel, hold that freewheel removal tool for another time.
I have disassembled the fw without removing it from the wheel too. I never had a pin spanner that I haven't immediately broken, so I use the "tap the outer race CCW with a punch" technique. You have to get the angle correct, otherwise you don't impart spinning force on the race. Lots of light taps, only increasing in force until you start to see movement. Once loose, you can easily spin off the outer race. Do not pull off the fw cog(outer body) just yet! First, remove the shims with tweezers and the outer balls with a small magnet. Get 'em all and keep them separate. Hold the fw body and then flip the assembly over so the small cog is down. If you've done it right, all those balls in the inner race have not tried to escape. Once upside down, you can lower the cog body and most of the balls will stay in the inner race. Some will be knocked out by the pawls springing out, though.

Collect all the balls and pawls, clean everything.

Flip the outer (cog) body upside down and apply a bead of grease in the body races and stick the balls back in a row on the inner race.

The rubber band trick Sheldon mentions with holding the pawls depressed is not what I use - I cut maybe 5 mm wide x 40mm strips of strong tape which I take a bit of the tack out by sticking it once or twice on my skin (this is the real trick). The tape will hold down the pawls which are stuck to the inner body (if there is no grease or oil just there) and allow you to mate the upside down outer body with balls with the inner body with pawls - and later will allow you to pull on the end of the tape and the tape will release. Flip the assembly over while holding it together, and hopefully you will have both (or three) strips of tape pointing out the front end. You then can pull out the tapes, and the pawls will be released (if the tape strips break, you have to start again). If you've gotten this far, the outer ball race then gets it's grease and balls, then put in the shims, then screw in the outer race cone and tighten well with taps in the opposite direction. It's gotta be tight, or it may loosen as you ride - you won't be happy if this happens!

Freewheel disassembly is only for the die-hard tinkerers or OCD sufferers. You can clean the fw with solvent and oil it without disassembly. But it is a challenge, and it beats learning how to win at chess!

I suppose you have also discovered that you can take the cogs off without disassembly of the freewheel body. You can make a pair of cog tools or you can buy one - this will allow you to clean the cogs and also alter the ratio if you can find other tooth cogs. Some cogs have orientation which you should keep track of as you take them off, though, otherwise shifting may not be smooth.

alecw35

as said theres some thin shims...or washers at the front of the freewheel innards

if the body of the freewheel rocks a lot, you can take one out.
I tend to put the thickest shim at the very front. So the thin ones arent bent.

You can get ball bearings to replace them. If they go a wandering.

I dissmantle the freewheel above a big plastic box. So all the bits fall into it.
Then clean the bits and put them in another box.

Some cheap freewheels dont have any way of removing them from wheels
mostly bmx ones.
so I take them to bits then rebuild them

BCRider

Definetly words to follow.

I've done them over a big box like this and also over an old towel. The towel does a great job of not letting the balls roll away as does the box. They do bounce a little as they clear the edge of the hub and hit spokes on the way out so be sure the box or towel is a larger one. And they are about .060 to .070 in diameter and there's a LOT of them so take care.

A medium weight oil is the lube of choice for these. Grease will produce too much viscous drag in the bearings and it can prevent the pawls from snapping sharply into place on the teeth with the risk that they'll catch only half way and tear the lips. I like to use chain saw bar oil. It's cheap, thin enough to let the freewheel parts work well but thick enough to resist a few seasons of our North"Wet" region rain commuting. I use it for my chain lube as well. And oddly enough it occasionally is used in my electric chainsaw...

nahh

thanks a lot. this is all great advice!

i have some chainsaw bar oil, and i was actually wondering if that would do the trick. so thanks a ton for confirming it for me.

will update to tell how it all went after it's completed.

Berre

I have disassembled and assembled many freewheels.
A trick: but a large piece of (thick) cloth on the table to catch the 75 balls. An old curtain will do. This way they won't jump in all directions.