1/8 Inch Cogs Compared: Sturmey Archer vs Two Threaded Cogs

 Let's compare a couple recent offerings in threaded cogs compatible with old-style Sturmey Archer threaded drivers. To keep things simple, all cogs are 1/8 inch wide because that is the traditional size for a Sturmey Archer hub. All of the cogs are 22 teeth large, a common size that people use to make climbing hills easier. The cogs must be relatively affordable, newly made, and relatively easy to buy (e.g., find it on eBay, Amazon, online bike shop, etc.). Lastly, let's compare these cogs to a basic, new Sturmey Archer 22 tooth cog for the usual 3-spline driver. 

Fronts of the cogs: L- Vuelta, R- Action

 

Offering 1: Vuelta brand threaded cog. (on the left in the above photo)

• Price: $18.00, including shipping.
• Source: eBay
• Style: matte chrome type finish, slotted for weight reduction, rounded profile teeth.
• Other Notes: comes with a lock ring for fixed gear bikes. 

• The Vuelta cog threaded onto the old style Sturmey driver without any issue. There is a lip one side of the cog to add extra threads and allow spacing by flipping the cog over. Sturmey Archer users will probably just use a spacer ring. Teeth are uniform 1/8 with no signs of manufacturing lines or roughness. Sizes available seem to be 15 teeth up to 22 teeth. The cog is not dished at all, but does have that lip that allows you to flip over the cog to set your spacing, if need be. The back side of the cog has the manufacturing information printed on it. It's not obvious or to noticeable, but be warned that if you want a totally plain looking cog, one side does have manufacturing information on it. I couldn't readily find the country of origin. 

 

Back sides of the cogs: L: Vuelta Cog, R: Action Cog

Offering 2: Action brand threaded cog. (on the right in the above photo)

• Price: $21.00, including shipping
• Source: Amazon
• Style: matte nickel finish, multiple round holes for weight reduction, old style pointed profile teeth
• Other Notes: does not come with lock ring but has deeper lip on one side.

• The Action cog also threaded onto the Sturmey Archer driver without an issue. The lip on this cog is larger than that of the Vuelta. There are also more threads on this cog than the Vuelta, because of that deeper lip. This cog has old-style, pointed teeth versus the Vuelta's more modern round tooth. This cog also is not dished. Instead, you flip it over and use that lip to set the spacing. Manufacturing quality seems alright, though the cog I received did have some residual manufacturing lines running along the edges of the cog teeth. The Action logo is tiny and engraved on one side. You'll barely notice the logo. The matte nickel type finish has a retro kind of appeal. There's a kind of "steam punk" element to the multi-hole weight saving. This cog did not come with a lock ring, so you may want to consider that if you're using a fixed gear Sturmey Archer hub (not a common thing, but they're still out there...). Allegedly these are made in the USA, according to the ad. I don't see a country of origin on the cog itself. All teeth are 1/8 inch.

 Tooth Comparison:

Vuelta Cog

Above is the Vuelta cog. Photo shows the relatively modern style rounded tooth profile with pronounced ramps for the chain to slide onto the teeth.

Action Cog Teeth

Above are the teeth of the Action cog. These are more traditional teeth with points and a less pronounced ramp. Manufacturing lines are visible along the teeth.

L- Action Cog, R- Vuelta Cog

Above, you can see the Action cog on the left has a deeper mouth than the Vuelta on the right. The Action cog has a couple extra threads and a little more range for spacing if you flip it over on the driver. The Vuelta cog comes with a lock ring, which is something you want if you're running a fixed gear Sturmey hub. In either case, you'll get more precision spacing by going with your regular Sturmey disc spacers.

Control Comparison: Sturmey Archer Three-Spline Cog

• Price: $8 to $15 usually.
• Source: Amazon, ebay, lots of places
• Style: chrome finish, traditional three-spline Sturmey cog.
• Other Notes: readily available, traditional type cog

• This cog is what you normally get for the regular Sturmey Archer driver. They slide on, and you use the ring spacers to set the chain line. The cog is helpfully dished. Sturmey Archer information is engraved toward the inside edge of the cog, but it is not too noticeable. Tooth profile is pretty generic. It's mostly a traditional tooth style, though I note the teeth are a bit more rounded and modern in profile than the originals from the 1950s and 60s. This cog looks fine on most bikes, but it is a bit bright and "new looking" if you're putting it on a very old bike. You can't argue with the price usually - they're not all that expensive. I believe these are made in Taiwan with the other Sunrace/Sturmey offerings of today. All teeth are 1/8. There's a little play as it goes onto the splined driver, but the snap ring holds it down well enough. If you mess up your chain line, it's MUCH easier to fix it with this cog than with the thread-ons. These cogs pop right off, whereas pulling the threaded cog may mean pulling the driver and getting out the chain whip.

 

Sturmey Archer Modern Cog

The above Sturmey Archer modern cog shows a kind of hybrid tooth profile - less rounded than the Vuelta, but more rounded than the Action. It has fairly substantial ramps for the chain sliding onto the teeth.

 

Final Thoughts: I would have no objection to using any of these three cogs. Each went on the drivers OK, and each is reasonably well made. The Vuelta was a little cleaner in terms of manufacturing marks than the Action, but the Action is not all that bad. The nickel finish and round holes of the Action give it a kind of "steam punk" retro look. The Vuelta is "all business" with its slotted cuts and more modern tooth profile. Unfortunately, neither modern threaded cog was dished like the old thread-one Sturmeys. Unfortunately neither modern thread-on cog had a dark blue finish like the old Sturmey threaded cogs. The Sturmey Archer three-spline cog also was reasonably well-made. It's a little bright if you're putting it on a really old or worn bike, but it will work.  

If you want to run a threaded driver and cog and you are running an old school roller chain (Perry, Union, Raleigh, Diamond, etc.), then I'd lean toward the Action cog. If you're running a modern chain (e.g., SRAM, KMC, etc.), then either threaded cog will work. With a modern chain the Vuelta would run a little smoother, but either would be alright. With either of the threaded cogs discussed here, you need to get your chain line right the first time, or else have to pull the driver, remove the cog, and start over with the set up (a real pain!).

The main issue is these threaded cogs are much more expensive than the Sturmey. I was easily able to find three-spline Sturmey cogs for around $10 new. Even the more expensive sellers were in the $15 to $18 range. The threaded cogs both were in the $20 range or so (Vuelta a little less, Action a little more). The lock ring in the Vuelta set is nice if you have a fixed gear hub, but a basic AW type hub won't really benefit from that. 

But at least you have a couple decent, affordable options for cogs if you really want to use that old school Sturmey Archer AW with a threaded driver. It's easier to swap to the three-splined driver, but why not also put those threaded drivers to good use?

 

 

Tool Tip: Removing Cogs from Threaded Sturmey Archer Drivers

 Older Sturmey Archer hubs, such as AW hubs from 1951 and earlier, have threaded drivers rather than three-spline drivers. This makes removal of the cog more difficult because it is screwed onto the driver rather than snapped-in using the circlip spring.

As the rider rides the bike, it tightens down the driver to a point that it is very firmly in place on the driver. 

 

 

Here is how I remove these threaded cogs:

1. Remove the driver from the hub. Remove the dust cap and bearings. Clean the driver and check that the bearing surfaces are clean and not pitted.
2. Put a stout adjustable wrench into a strong bench vise. Don't use a clamp-on vise for this; use a bolt-down vise on a heavy work bench. 
   
3. Slide the driver onto the thick end of the wrench handle close to the jaws of the wrench. Make sure that the wrench is slid well into the vise. There should be just enough room between the head of the wrench and the side of the vise that the driver can fit. See the above photo and below photo for the positioning of the wrench in the vise (note how close the head is to the vise - it's not sticking way out).   
4. Mount your chain whip (again see the photo above and the one below). Connect to as many teeth on the cog as you can.
5. Trickle some Kroil or similar creeping oil into the threaded joint between the cog and the driver.
6. Heat the cog around the threads using a propane torch. Heat it evenly going around and around. Keep heating gradually until the Kroil in the threads begins to bubble. CAUTION: if you heat it too much, you will start a fire or smoke out the oil.
7. Apply a little more Kroil to the heated joint. Let it cool for a couple of minutes.
8. Begin ramping up torque on the chain whip. Gradually build up you pull.
9. Apply additional heat and Kroil if the cog won't move.
10. Repeat until the cog unscrews.  
11. Carefully remove the cog, spacer(s) and dust cap. CAUTION: they are hot.
    

Once you get the hang of this, you should be able to save many of these old, threaded drivers. Your threaded driver is now able to take a larger rear cog (track style cogs will thread-on), or even a thread-on multi cog, such as a Cyclo bloc for hybrid gearing.

 

New Arrival: Another 1947 Schwinn Continental

 

Here's another find and yet another project: a 1947 Schwinn Continental. I owned a similar bike some years ago, but ended up selling it back to the previous owner when I had to move.

This bike is very similar: standard frame size (about 22 inches), same color (aluminum-blue), and good condition. The rear hub is an undated Sturmey Archer AW hub, and the front hub is a duraluminum Schwinn type.

The frame is Chrome-Molybdenum steel with thin tube walls. It has the usual three-armed spider, 46 tooth chain ring, and cottered cranks. 

 

The brakes are Schwinn-built steel calipers. It is missing the Schwinn brake levers and the desirable (expensive) double-adjustable stem. I'll source some replacement parts that will work for this bike.

These bikes are good riders, and fairly light in weight for their time. The lightened Schwinn stainless S6 rims are a big plus on these bikes.

 

The fenders are made of fairly thin stainless steel. They have the wire braces that connect to the Continental type frame braze-ons.

This bike even has its original bike shop sticker on it, from a shop that sold bikes and baby carriages in New York City.

This project is already taken apart for cleaning and rebuilding.

1951 New Hudson Silver Arrow

 

The New Hudson Silver arrow project is finished for the time being. I won't have a chance to test it out until the riding season starts in the spring. It also will need some light cosmetic work, but for the most part, this one is done. 

 

The Silver Arrow was a mid-level offering from New Hudson / BSA. The bike has Reynolds 531 main tubes on the frame. It has club bike style equipment, but a laid back frame similar to a roadster bike. 

The wheels are 26 x 1-1/4 (ISO 597mm) club types. The rims are Dunlop "lightweight" steel endricks. The front hub is a basic steel hourglass with oiler port, and the rear hub is a Sturmey Archer AW 40 hole from the 1950s. This is a 23 inch frame riding on 26 in wheels, a size I particularly like.

 

This bike is built with North Road type bars rather than the stock drop bars because the North Road is more comfortable for me. 

The bike has peculiar, proprietary BSA/New Hudson brakes with pad holders that sleeve onto the caliper arms perpendicular to the rim surface. The pad holders take John Bull style brake pads. I was able to buy reproduction pads that fit the pad holders. The cables are double-ended proprietary types, similar to Raleigh cables, but with somewhat different cable ends on them.

 

The original Bluemels New Hudson celluloid fenders were destroyed when the bike was shipped to me. I used the claim money to buy a very nice set of replacement Bluemels and added a New Hudson decal from H. Lloyd's in England. 

 

This bike is the third in a series of "sporty roadsters" I did over the course of about a year. The first was a 1953 Raleigh Lenton, the second was a 1949 Raleigh Clubman, and the third is this New Hudson Silver Arrow. The concept was to put blend light roadster ergonomics with sporting or club bike style frames and equipment. This is a style of bike that had somewhat of a following in the 1940s and 50s, but which eventually fell out of favor.

And now comes the wait until spring to see how this one will ride...