Overhauling a Freewheel, Part I

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1941 French 3 Speed Freewheel

Vintage bicycles generally use freewheels, and not freehubs, as part of their drive trains, although it is interesting to note that the first freehub was actually invented by the British company Bayliss-Wiley back in 1938, and used thread-on cogs. Later, BSA created a splined freehub in 1948, which was set up for 4 cogs. And, Stronglight, Maxi-Car, and a few other manufacturers developed and marketed cassette freehubs in the late 1940’s through the 1950’s.  Shimano came out with its first freehub in 1978, and the rest is history.  Freehubs with splined cassettes are now the standard equipment on all modern bicycles.

Shimano, Sunrace, Ventura, DNP and IRD still manufacture freewheels, but the style, number of speeds, and spacing of the cogs, as well as the overall width of the freewheel often makes them inappropriate choices for a vintage bicycle restoration project.  Plus, weight and reliability can be an issue with any new non-Shimano freewheel (see below).

It is still possible to find NOS or good quality used vintage freewheels, such as Suntour, Regina, and Cyclo, on eBay or even Craigslist, but sometimes the cost is just too high to justify the expense in dollars.


1940’s Cyclo Freewheel

I can attest to the reliability of virtually all vintage freewheels, having had no failures even after riding and restoring hundreds of bicycles. With a bit of lubrication, by dripping automotive oil into the space where the freewheel turns on its body, most freewheels can be brought back to their original functionality.  Sometimes, with a very dirty freewheel, I will first lubricate the body with a light oil, to clean the debris out, then follow that up with heavier automotive oil (the same 30 weight that I use for lubricating internal hubs).  The 1940’s freewheel pictured above came back to life easily after this simple process.

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1929 Peugeot Freewheel and Fixed Cog

Some freewheels don’t even need that much attention.  This 1929 Peugeot single speed freewheel with its helpful hinged lubrication port (part of the 1929 Griffon that I am restoring) didn’t require much lubrication – it was still working perfectly after 87 years of service!

Freewheels require a precise bearing adjustment, accomplished by the use of spacers and the torque on the cover plate.  While pawls can wear out over time, the stress on the bearings themselves is quite low, compared to bearings found elsewhere on a bicycle, and that is one reason why so many older freewheels work perfectly with simple cleaning and lubrication.  Hence, some mechanics have never found the need to perform a freewheel overhaul, myself included.  There are a number of resources on the web which provide detailed freewheel overhaul instructions.  There is even a business called the “FreeWheelSpa” which has dedicated itself to this zen-like work. Not wanting to deprive myself of the joy of tearing apart a mechanical device on a grey, rainy Portland winter day, I decided to tackle the job myself.

My Suntour New Winner 7 speed freewheel, installed on my winter bike, had begun making clunking sounds while under load, and grinding sounds while freewheeling.  I replaced it with a different vintage freewheel from my dwindling stock so I could keep riding the bke, but before attempting to overhaul the Suntour freewheel, I decided to take apart a number of other vintage freewheels on hand, to make sure I understood the process.  Possibly, this was a bad idea.

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From left to right: French freewheels, including Cyclo, Atom, Maillard and Milremo, Suntour freewheels including Perfect, New Winner, and Pro-Comp, and various Shimano and Shimano copies, both vintage and new.

I have a small collection of vintage French and English threaded vintage freewheels, plus a number of newer freewheels from Shimano, IRD, and DNP.

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This is an IRD freewheel that had previously failed after only a few hundred miles.  I marked it with a zip tie so that I would never use it again.  This seemed like the first obvious choice for an overhaul in my quest to master the freewheel overhaul process.  Unfortunately, the cover plate on this freewheel could not be removed, even after much pounding on the cover plate with a punch and hammer.  After that failed experiment I tried removing the cover plates on all the newer Shimano and Shimano copy freewheels on hand.  In each case, the cover plate could not be removed, partly caused by the tinier holes present on the newer freewheels – which would not accept my Park pin spanner.  Clearly these freewheels were meant to be tossed when they failed, part of the now de rigueur built-in obsolence doctrine in the cycling industry.

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So I grabbed an early 80’s made-in-Singapore Shimano freewheel, and had no trouble at all getting the cover plate off.  You need to mount the freewheel to a wheel first, before attempting to loosen the cover plate, so that the freewheel body is held in place.  I used an old rear wheel with English threads that I didn’t mind abusing for this process.  Once the cover plate is loose, you want to remove the freewheel off the wheel, and the take the cover plate off.  The cover plate is REVERSE THREADED, so you turn it clockwise to loosen it.

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When the cover plate was off, I was able to see the first set of 1/8″ bearings resting quietly in the top cup of the freewheel body.  There is another set of bearings at the bottom of the freewheel body.  I used my magnet to remove the bearings, and placed each set of bearings in a separate container.  I did not intend to replace the bearings, so I cleaned them with a little alcohol and let them dry out, planning to re-use them.

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Then I applied a bead of grease to the lower cup first, and began the mindful process of placing each bearing back in its rightful spot.

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Shimano freewheel pawls

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Maillard pawls on the left.

But, before doing so I noticed that this Shimano freewheel’s pawls differ substantially from this earlier Maillard freewheel that I had previously disassembled.  The Maillard’s pawls are held in place only by gravity, and there is one pawl on each side of the freewheel body, but the Shimano has double pawls on each side, held in place with a clip.

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After the lower bearings are installed, you need to screw the freewheel body back onto the wheel, then very, very carefully put the freewheel cogs over the top, and seat the pawls.  That’s where I ran into trouble, and decided to take a break before proceeding further.  It can be quite tricky to get the pawls back into the ratcheting mechanism.  Sheldon Brown used a technique involving a rubber band and some thread.  Reading about it gave me a headache.

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Meanwhile, my failed IRD freewheel is taking up its rightful position as a doorstop.