How to Rebuild Your Singlespeed Freewheel

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Editor’s note: This article by Brad Quartuccio and Michael Browne first appeared in Dirt Rag Issue #96, published in October 2002.

Singlespeeders are obsessed with simplicity. No derailleurs to mess things up, no shifters to backfire and leave you stranded. But what happens when one of very few moving parts stops working? Most people think you just have to replace the freewheel when it starts to feel sticky or when there’s a bit of side-to-side play. Sometimes you’ll notice it when you’re walking with your bike—when the cranks pedal by themselves despite a properly fitted chain. It might even skip during a pedal stroke. Brad says it’s time to rebuild when “it just feels mucky.”

So, if you know it’s time to figure out how to make your life better by rebuilding your freewheel or you just want to hang around and learn something, you’re in the right place. After you find the following list of things, clear off a space on the workbench.

Supplies needed:

1 freewheel removal tool
1 small flat-bladed screwdriver (use a magnetic one if you have it)
1 red Park pin spanner
2 film canisters
1 grease gun (cause it’s handy)
1 bottle degreaser
1 rag

Disassembly

1. Remove wheel from bike. Leaving the freewheel threaded on the hub, grab your spanner tool and insert it into the two shallow holes. This is a left-hand thread, so loosen by turning clockwise. Loosen the freewheel cover about an eighth of a turn.

2. Using the freewheel removal tool, remove the freewheel from the hub. This has a right-hand thread, so stick with the righty-tighty lefty-loosey rule on this one.

3. Remove the cover that you already loosened. There are a bunch of bearings in there, so once the cover is removed, try not to move the freewheel much—96 bearings (48 per side) could go a flyin’.

Be careful when removing the cover. There are extremely thin washers that stick to the cover. Do not lose these; they are the key to a successful rebuild.

4. Now, start taking out the bearings with your screwdriver. See how a magnetic screwdriver could be pretty handy? Save the bearings in a film canister.

You can see why a magnetic screwdriver is helpful in removing the bearings.

5. Now, lift the chainwheel up off the carrier. You should see 48 more bearings. Notice how similar the freewheel is to a hub—bearings, cups and cones, oh my! Get out your other film canister to store the lower 48.

The goods (clockwise from top left): cover and spacers, bearings, carrier, chainwheel.

6. Now, take a look at how the thing works. Check out how the pawls (the little ratchets that make every hub go ‘tick’) spring back into place. Now, grab your rag and degreaser and thoroughly clean all the parts. Put some degreaser in the film canisters and shake ‘em up.

Spinning the freewheel without the cover installed lets you see how the pawls and springs function.

7. Inspection: Here’s where you find out if rebuilding the freewheel is hopeless or fruitful.

Reasons to buy a new freewheel:

pawls are cracked or scored
engagement teeth show excessive wear
chainwheel shows hooked teeth

Rebuilding

8. Now that all the parts are squeaky clean and you have them laid out on a clear and clean surface in front of you, find the carrier. Lay it flat and fit the toothed piece on it while turning counter-clockwise. When it fits together, you should be able to spin the ring and watch the pawls engage.

9. Now that you know how it fits together, remove the chainwheel, remembering which side goes up. On the back side of the chainwheel, line the bearing race with a thin layer of grease. Carefully place each of the 48 clean bearings onto the race, using the grease to hold the bearings in place.

10. Now, slide the carrier back onto the chainwheel. You may have to engage the pawls with a screwdriver to drop it in properly.

The grease actually helps hold the bearings in place during reassembly.

11. Now, repeat the grease and bearing procedure on the other side, leaving the already assembled pieces in place.

Too much grease can render your overhaul useless.

The key to the whole operation

If your bearings felt sloppy before, try removing just one of the really thin washers. These are included so you, the consumer, can compensate for wear on the bearing races. You’ll know you didn’t need to take a washer out if when completely reassembled, the freewheel doesn’t turn smoothly. If this happens, take it apart and add the washer, realizing you’re a better person for seeing the inside of a freewheel again.

12. Now, with all your washers in place, thread the cover back onto the freewheel. Remember, it’s left-hand thread, so thread it on counterclockwise. Using the spanner tool, tighten the cover. Brad says he tightens it as much as he can in his hand without tearing his skin. Now, hopefully your freewheel will spin smoothly and freely. If not, tear it apart and do it again.

13. Install on your bike and spend the ten bucks that you saved on something different. Or buy one anyway, cause there is a point where the freewheel is just dead.

Maintenance

To keep your freewheel happy without rebuilding, drip some lube on the seams and spin by hand. If that doesn’t work, try soaking in WD-40 overnight, then reapply lube liberally.

Karl likes Boeshield T-9 because it’s designed to penetrate, clean, displace water and leave behind a paraffin wax film that lubricates the innards for many a mile.

Keep reading

We’ve published a lot of stuff in 26 years of Dirt Rag. Find all our Blast From the Past stories here.