Sturmey Archer Hub Gear Ratio Notes

One of the nice things about Sturmey Archer AW hubs with the 3-spline cog is that you can change your gear ratio as needed.

For Sturmey Archer AW sizing in a 26 inch wheel I like:

[Front] - [Back]

(Note if you are running a conversion cog and inch pitch gearing, divide these numbers of teeth in half)

Very Hilly Terrain:

2-1 (46-23), (48-24)- this ratio is the max low that Sturmey Archer suggested back in the day for the AW hub. They suggested not going lower because they believed it exerted too much force on the hub internals. I've not tested this theory, but 2-1 is pretty low. N is mostly a climbing gear but not bad on a flat into the wind. I suppose you could go lower, but I don't press it with older hubs and I stick to the old Sturmey Archer advice. Perhaps the modern hubs will tolerate it, but I haven't messed around with new hubs much.

Moderately Hilly: 

46-22, 48-23- works reasonably well. Goes OK on a flat. Can climb in L, or smaller hills in N. Has slightly more top end than 2-1 but not much.

Somewhat hilly, or if you like a lower gear a little below stock: 

46-20, 46-21, 48-22, 48-21- Climb mostly in L, N is peppy enough to run well on a flat or into a breeze. I like this ratio for all-around riding. It's a little slower than stock, but I like how it lets you "spin" a little more and is easier on the knees than stock.

Flat:

46-18, 48-18 (18 is stock), 48-20- I think Sturmey Archer set the stock gear ratio too high on these hubs. 18 strikes me as not making the most of that low gear for climbing. On a flat, stock goes well (or 20 on a 48 tooth sprocket), but your climbing is somewhat limited and you may need low gear for going into the wind. I don't run any of my AWs with an 18 tooth cog anymore.

Top end boost:

46-16, 48-16 (this is if you want a really high gear and a lot of top end speed) I fooled with this briefly but didn't like it. It's fast but you had better live in a very flat area.

FW and SW Notes:

The rule I follow for the FW-  the gear ratio when converting between AW and FW is that the FW should be 1 tooth on the rear cog higher (smaller cog) than for the AW. The reason for this is that the FW has a lower high gear than the AW does, while providing a bottom gear. The second gear "L" is slightly higher than the AW's L but the AW doesn't have Bottom. That said, if you want max climbing, go 2-1 on the FW and you'll have better climbing than the AW.

For the SW, I don't like changing the ratio substantially because the hubs tend to cam-out more if you put a big cog on the rear, at least in my experience. I also suggest swapping out the SW on any bike you're going to ride substantially, or be climbing with. The AW is the way to go over the SW.
 

For Sturmey Archer sizing I like:

[Front] - [Back]

Very Hilly Terrain:

2-1 (46-23), (48-24)- this ratio is the max low that Sturmey Archer suggested back in the day for the AW hub. They suggested not going lower because they believed it exerted too much force on the hub internals. I've not tested this theory, but 2-1 is pretty low. N is mostly a climbing gear but not bad on a flat into the wind.

Moderately Hilly: works reasonably well. Goes OK on a flat. Can climb in L, or smaller hills in N.

46-22, 48-23

Somewhat hilly, or if you like a lower gear: Climb mostly in L, N is peppy.

46-20, 46-21, 48-22, 48-21

Flat:

46-18, 48-18 (18 is stock), 48-20

Top end boost:

46-16, 48-16 (this is if you want a really high gear and a lot of top end speed)

For Sturmey Archer sizing I like:

[Front] - [Back]

Very Hilly Terrain:

2-1 (46-23), (48-24)- this ratio is the max low that Sturmey Archer suggested back in the day for the AW hub. They suggested not going lower because they believed it exerted too much force on the hub internals. I've not tested this theory, but 2-1 is pretty low. N is mostly a climbing gear but not bad on a flat into the wind.

Moderately Hilly: works reasonably well. Goes OK on a flat. Can climb in L, or smaller hills in N.

46-22, 48-23

Somewhat hilly, or if you like a lower gear: Climb mostly in L, N is peppy.

46-20, 46-21, 48-22, 48-21

Flat:

46-18, 48-18 (18 is stock), 48-20

Top end boost:

46-16, 48-16 (this is if you want a really high gear and a lot of top end speed)

1940 Schwinn New World

The 1940 Schwinn New World project nears completion. Just a few final adjustments left. I removed the front spring from the knock-off "Brooks" saddle. I'll post a review of the saddle once I have more miles on it. I also need to get a saddle bag for the bike, probably another Banjo Brothers barrel bag. Now for the important part... pictures.

 The "four peg hole" sprocket looks a lot like the more common "cloverleaf" from the 1950s-60s, but is actually a much less common and earlier part. The telltale sign is the four holes toward the center of the sprocket.

This is the original Yale key for the locking fork. I had a duplicate made for use while riding.

1940 Schwinn New World

Still working on a 1940 New World project I picked up this fall. I've had to manufacture a few small parts for it, tweak a few things, and adjust a few things, but it is starting to come together.











The bicycle is a mix of old and new. The rims are Sun CR 18 aluminum types. The spokes are stainless, but the hubs are vintage. The rear is the uncommon Sturmey Archer alloy and the front is a Schwinn Script hub. The tires are new Kendas in the English ISO 599mm size.









Shifter is a 1940s Sturmey Archer quadrant, but the shifter cable is new. Grips are reproduction coke bottles.













The stem originally was from a Schwinn Cycletruck, but someone cut it down. I re-shaped it with a Dremel tool to accept a normal wedge. The AS bolts on the stem are reproduction, as is the AS seat bolt. The saddle is a generic, but still leather, reproduction. Rear reflector is original glass Stimsonite.










Brake calipers are original "Schwinn Built" type, as are the brake handles. Pedals are AS stamped originals.

Last Project of the Year

I have spent the fall catching up on projects sitting in my barn. This included the Manton & Smith, 1959 Schwinn Tiger, and a 1940 Schwinn New World.

This particular New World arrived as a bike "core": frame, chain guard, fenders/braces, fork/headset, seat post, partial crank set, stem, front brake caliper, and handlebars.

I took apart the core down to the frame, cleaning up everything. Here is the frame along with a complete, 1947 New World for comparison. They're very similar and the differences are subtle, but present.


I also have an array of really nice parts for this build. This box includes: Arnold/Schwinn "AS" stamped pedals; an uncommon, aluminum alloy Sturmey Archer hub from 1954; an original Schwinn script front hub; a matched set of Schwinn brake levers; and a matched set of "Schwinn Built" calipers.






The rims will be Sun CR18 aluminum rims in the English (ISO 590mm) size. Spokes will be straight gauge DT Swiss stainless. I also have a pristine, original Sturmey Archer quadrant shifter to add a nice, period touch to this relatively early New World.

1959 Schwinn Tiger Middleweight

Next on my list of projects was a 1959 Schwinn Tiger. This is a classic Schwinn with the cantilever frame, painted fenders, and chrome S7 rims.

The concept here was to build a middleweight cruiser bike with some "adult-oriented" upgrades. This meant heavier duty seat, heavy duty seat post, wider handlebars, multispeed hub, and slightly fatter tires.
















The result is a pretty nice bicycle. The multispeed hub is a Sturmey Archer 3 speed coaster brake (modern). The cable routing is custom fitted so as not to disturb the frame lines. Tires are Schwinn middleweight sized, but slightly fatter "cruiser" tires.
















The bike is fun to ride, and the upgrades are welcomed additions making it a better machine for an adult who wants to get more out of a middleweight that just a short-distance, single speed bike.

They are not true balloon tires, but are a 50 psi, slightly fatter version of the Schwinn middleweight tire. 

A Nice Box of Parts

While things were pretty busy, I got a few minutes last night and tonight to clean up some of the better parts I have sitting in the shed. It's definitely roadster oriented.

The parts are:

1 pair of "Schwinn Built" 1940s era calipers (need to make new pinch bolts for them still)
1 pair of "AS" Schwinn pedals (rebuildable type)
1 1954 Sturmey Archer Alloy hub (36 holes, uncommon Alloy variant)
1 pair of Schwinn brake levers (1940s)
1 Schwinn Front hub (just arrived yesterday, shell cleaned up nicely)

Manton and Smith

The Manton and Smith custom bicycles is basically done. I had only a few spare minutes this weekend, but took a few shots. The frame is 21 inches from bottom bracket to the top of the seat tube. However, the frame has a very large amount of lay back, making it ride "bigger" than most 21 inch frames. This frame is actually too large for me in terms of the reach to the handlebars. A taller rider might love it though. I think this one will be going on the block to make room for a couple other projects I have out back.

Manton and Smith Continued

The Manton and Smith is starting to come together. I also added the smaller size coke bottle grips and a 1950s era "brown letter" Sturmey Archer shifter.

The top sports a white "dart" design like the frame, and the lower edge of the crown lug is outlined in matching red. I did some detailing on the fork crown to further tie it into the design. The bracket/fork bolt is in place and just needs to be cut to length.
















There is still some adjusting on the wheels/axles to do. But the wheels seem to fit nicely.




















I mounted a "universal" McCauley chrome chainguard. It works well with the fork and the theme of the bike.













It's not done yet, but getting there.

Manton and Smith Wheel Set

I have finished the Manton and Smith wheel set. The front wheel is similar to the rear with a couple small differences. First, the front hub is a vintage, 36 hole Sturmey Archer hub from a 1970s Raleigh Sports. Second, the front hub had narrower flanges and required the use of brass spoke washers. Other than that, it's largely the same as the back: DT Swiss stainless straight gauge spokes, 12mm nipples, and a Sun CR18 rim in polished aluminum alloy. Tires are Schwalbe Delta Cruiser creme in the ISO 590 (English 26 x 1-3/8) size.

Manton & Smith Rear Wheel

Tonight involved a test fit of the rear wheel I built for the MS bicycle. I am leaving the original wheels alone, and building my own as riders.

These wheels are Sun CR18 polished aluminum rims in the ISO 590mm (English 26 x 1-3/8) size.  The rim in the picture is finger print smudged, but it is polished on the top. There is a wider variety of tires available for that size than the Schwinn (ISO 597mm) size.










I decided to go with the Schwalbe Delta Cruiser creme tires to match the accent paint on the bike. It goes nicely with the red. Also, I slipped rubber spacers between the fender and fender bridge to cut down on rattle and creak while riding. Modern hardware with a lock washer prevents the fender stay screw from loosening through vibration.






The hub is a Sturmey Archer 3 speed coaster brake with an alloy shell. Spokes are DT Swiss straight gauge stainless. It's basically an old style English 3 speed type wheel, but with modern parts and a coaster brake. The concept is to keep the best of the old and combine it with new materials and parts in creating a nice wheel.






These wheels should have plenty of comfort with the Schwalbe tires, but should have a little extra kick on the downhill using that high 3rd gear of the Sturmey Archer hub.

Manton & Smith Bike Continues

The MS bicycle project continues to take shape. The bad news is that the fork was cracked around the crown and down the drive side leg a bit. I believe it could be fixed and straightened, but there would be a substantial loss of the unique paint job, and the bill for the repair would be substantial. I'd probably be looking at a new steerer tube and a substantial braze or weld job on the drive side leg.

The upshot is that I've bought a 26 x 1-3/8 chrome replacement fork. These forks can be bought on Amazon or ebay for relatively little money, are made of mild steel, and are reasonably solid. They have a "retro" look to them, which can be made to work with this bike.

More bad news came in the form that the headset on this bicycle was an oddball dimension. I could not even get vintage, mainline "American" sized parts from the 1950s to work. Apparently this bike used some sort of other size that is neither the common "vintage American" size, nor the more modern "ISO" size. I ended up removing the frame cups and headset, replacing with a Wald unit, which is fitting given so many of the parts on this bike were already made by Wald.

In the end, this bicycle is headed a little more toward "custom" than the usual build, but so far that seems alright. The bike has a little of the look of the earlier lightweights, which often had plated forks mated to wildly painted frames.

Progress continues with more assembly. I've nearly gathered all the parts at this point.