Do Sturmey Archer AW Parts All Interchange?

One question that comes up fairly often is:

"I have a problem with my Made in England Sturmey Archer AW and need a replacement part. Do all AW parts from 1936 through the early 1980s interchange?"

The answer often given online is "yes", but the truth is a little more complicated. The basic rule is this: most Sturmey Archer Made in England AW parts will interchange. However, the farther apart the years of your hub and the replacement part, the more likely you are to run into problems.

Let's start by removing "copies" - versions of the AW made in other countries or by other companies. These will be the subject of later writings. We'll focus solely on Sturmey Archer-made AWs from the main factory (see footnote on license-built or copy hubs).


Let's also remove the recent "no in-between gear" and Taiwan-made Sturmeys. Again, focusing only on main factory AWs.

 Here is a picture illustrating our rule - it shows an evolution of Sturmey Archer drivers, from left to right, taken from various AW hubs over the years.

The oldest is a threaded driver with simple, tapered tines. It dates to the late 1940s - early 1950s. It's relatively well-finished and is well-hardened. It takes a standard track cog or even can house a small freewheel for hybrid gearing (a derailleur with the AW in combination).

Next is a 1950s-60s era driver. This has plain, tapered tines but takes a three-spline cog and spacers. The thickness of the tines is actually slightly different than the earlier driver, but not by much. The second picture shows the tines are a little beefier than the threaded driver. They should interchange OK, but the shifting might not be quite as smooth.

Next is a 1960s era driver. At some point in the 1960s (I think), the factory began to re-profile the drivers, at least some of them. This driver has a very slight "hourglass" shape and some radiusing of the tines. The tines are also a little less beefy at the ends. I ran into trouble with this particular driver in a late 1940s hub. I found that the differences in tine shape and size made the "neutral" between Normal and High a bit bigger than should be. Do they interchange? Sort-of. The hub worked, but I didn't like the enlarged neutral, so swapped to a closer-in-size driver.

Finally, Sturmey transitioned to a totally different driver tine shape in the early 1970s (I think - this is what I can tell from the hubs I've seen). The later driver actually does away with the tapering and has "step-downs" profiled into the tines. The upper portion of the tines are broader, but the step-downs are narrower. This was probably done to smooth-out shifting on later hubs.  I once tried to put one of these in an early AW hub, and the shifting was a bit erratic. Does it interchange? Again, sort-of. The hub worked generally, but the shifting was not as crisp as the earlier, more correct driver. It can be used in a pinch, but if I was doing a lot of riding on the bike, I'd want a driver closer to the original.

So my verdict is: for the most part, Sturmey Archer AW parts interchange, at least the ones from the main factory. However, there are very slight differences in the parts over the years, that are not really accounted for in much of the literature online. My advice is to look for a part as close in era to your hub as possible. If you absolutely cannot find the part, go with the later era AW part.


Footnote: interchange falls apart to a degree in dealing with copies of the AW made in other factories. Parts from license-built hubs in Austria or from other brands are less likely to interchange with main factory AWs. I've had hubs not run properly using those parts.