STURMEY-ARCHER TRICOASTERS – and my 1914-15 FN Tricoaster in particular – by Peter Fuller

The Tricoaster hub, a combination of back pedal brake and three speed hub gear, has certain desirable qualities. The first is that there should be no freewheeling ‘no gear’ position between the gears, which would of course be very dangerous if found while braking. Secondly it is an advantage if braking is always applied through the Low gear train for maximum braking force regardless of the gear in use. Finally, as with any hub gear, it is an added bonus if a snapped cable does not leave the hub in High gear.

The model C Tricoaster of 1907 and the N and FN models that followed from 1910 to 1921 possess all the qualities listed above – on these hubs a snapped or slack cable gives Normal gear. Of the Tricoasters that followed, the KC of 1922-35 and the TCW series of 1952-72 did not apply the brake through the Low gear train regardless of the gear selected, and a slack cable gave High gear. The S3C, introduced in 1970, was a little better – it did have a ‘no gear’ position between Normal and High but this could not affect braking since in the S3C braking is always applied through the Low gear train, but a slack cable still left the hub in High gear. Of all the Tricoasters Sturmey-Archer designed up to and including the S3C of 1970, the earliest C, N and FN models were perhaps the best.

I had been having trouble with the back-pedal brake component of the Tricoaster on my 1914-15 Raleigh Special Roadster. It is fitted with an FN, an N type Tricoaster with the ‘fine’ axle thread adopted in 1914, becoming standard thereafter. The problem with my hub was that the back-pedal brake would only engage in warm weather. When tested on a sunny afternoon it would work fine, but tried cold the following morning the brake would not engage, the pedals just freewheeling backwards. Knowing, therefore, that it was temperature related, I hoped that a good clean up was all that was needed. I also knew it had not been serviced for about 10 years and that at its last service modern Sturmey- Archer gel had probably been used to lubricate it.

So, armed with an exploded diagram, I stripped it down to sub-assembly level (Fig. 1). I could not remove the screwed-on sprocket to service the right-hand ball ring since it appears a special tool is needed to do this.

Figure 1

The brake is applied by a worm drive, which was nicely gummed up in line with the diagnosis (Fig. 2). I cleaned everything up and set to work re-assembling using my preferred lubricant, SAE 30 four stroke lawnmower oil.

Figure 2

This is where I ran into trouble as these hubs do not go back together like the later types. In particular, adjustment of the right-hand cone is very different and although this expertise must surely reside somewhere in the club’s knowledge base I could find nothing online.

The procedure for adjusting the right-hand cone on almost any S-A hub from K Series on will be familiar to many – screw the cone up finger tight, back off half a turn, fit special lock washer, fit lock nut. On the FN Tricoaster the r-h cone/clutch screws up all the way until you run out of axle thread, without ever reaching a registration point. Scouring the early Sturmey-Archer catalogues on their Heritage website turned up unhelpful advice like ‘never disturb the right cone’, or worse ‘the right-hand cone is a fixture, and must on no account be meddled with’.  

A lengthy session with the exploded diagram and a description of the workings of the similar type V hub revealed that the three speed element of these early hubs works quite differently to later models.

These earlier designs operate by moving a sliding pinion along the axle. Normal and High ratios are achieved by engaging the sliding pinion with internally toothed ‘clutches’ at either end of its travel, Low being activated when the sliding pinion is in its central position disengaged from either clutch.

With the cable slack the sliding pinion is in its left-most position and engages with the internally toothed clutch in the compound planet cage giving Normal gear. One click on the lever pulls the sliding pinion out of this engagement, taking it out of play but enabling a Low gear train. A second click pulls the sliding pinion even further to the right engaging it with the internally toothed clutch in the r-h cone/clutch and providing High gear. The progression of gears on tightening the cable is therefore Normal-Low-High, dictating the design of top tube and handlebar levers to accommodate this in a logical way (Fig. 3). There is no ‘no-gear’ position with this sliding pinion design.

Figure 3

The sliding pinion principle is used in the C, N and FN Tricoasters and the V and A type three speed hubs. Generally, from the K series onwards, the familiar sliding clutch method is used to change gear.

The key to adjusting the r-h cone/clutch correctly on the axle is that it should be screwed on just far enough that the sliding pinion teeth are flush with the upper face of the internally toothed clutch in the compound planet cage (Fig. 4). The upper pinion seen is the fixed pinion, part of the axle. The teeth of the sliding pinion can be seen just below it, correctly adjusted flush with the surface of the internal clutch teeth in the compound planet cage.

Figure 4

If the r-h cone/clutch is not screwed far enough along the axle the fixed pinion could engage with the internal clutch teeth in the compound planet cage and probably lock the hub. If the r-h cone/clutch is screwed on too far, the sliding pinion might not be pulled to the right far enough along the axle to engage High gear. When it is correctly positioned on the axle, it should look like the one shown in Fig. 5.

Figure 5

Since I could find no servicing instructions for these hubs, I have documented the process below. I am pleased to say my hub is reinstalled in the bike and the brake has worked consistently since.

Sturmey-Archer FN Tricoaster strip and rebuild

The following notes refer specifically to the FN Tricoaster Mark 1 1914-1918. In terms of re-assembly, the 3 speed section at least could be adapted to apply to the C and N Tricoasters and model V and A three speed hubs – the sliding pinion group of hubs of that era. Part names and numbers referred to relate to the exploded diagram (shown below) of the FN hub available on the Sturmey-Archer Heritage website at:
http://www.sturmey-archerheritage.com/images/photos/pic-22.1.jpg  

Exploded diagram by Peter Read, downloaded from the Sturmey-Archer heritage website

I am not aware of any sources of spares for these hubs and would be pleased to know of any. These notes reduce the Tricoaster hub to its main sub-assemblies only, sufficient for cleaning.

To dismantle the FN Tricoaster Mark I to sub-assembly level

1. Remove the axle nuts and any spacers. It is useful not to disturb the relationship between N25 r-h cone/clutch and its star locking washer – to preserve this setting fit a spare axle nut to hold the star washer in place. If this setting has been disturbed refer to the reassembly instructions.

2. Unscrew and remove N6 l-h indicator rod and N7 r-h indicator coupling. N126 indicator spring may come out with the l-h indicator rod.

3. With the wheel horizontal, left-hand side up, remove the l-h locknut and N192 l-h adjusting nut/cone.

4. Lift off N152 brake plate & arm assembly and the N150 brake cone.

5. The axle complete with temporary axle nut, locking star washer, r-h cone/clutch and sliding pinion is now free to drop out of the right-hand end of the hub. It will be needed in place for step 8.

6. Loosen N34 r-h ball ring in the usual way using a punch and hammer. It has a two-start right hand thread. (At this point Sturmey-Archer instructions require you to mark the relationship between the r-h ball ring and the hub shell so that they can be refitted in the same orientation – I understand this to be a moot point).

7. Turn the wheel horizontal again left-hand side up and unscrew the mechanism by hand from the hub shell, keeping the l-h end uppermost. Note: the internal clutch nut N149 and Low gear cage (c/w worm drive) N164 are not secured – they could fall off if the mechanism is not kept left-hand end up.

8. With the axle in the mechanism and kept vertical, l-h end uppermost, clamp the r-h end of the axle in a vice.

9. Lift off N149 clutch nut assembly and N164 Low gear cage (c/w worm drive) assembly.

10. Remove the remaining mechanism from the vice and remove the axle assembly from N22 compound planet cage and driver and N34 r-h ball ring/drive sprocket assembly.

11. Unscrew N10 axle (internal) grub screw to remove N8 main axle spring if required.

To reassemble the FN Tricoaster Mark I

If the relationship between the right-hand cone/clutch, star washer and axle has not been disturbed proceed to step 5.

To check or reset the relationship between the right-hand cone/clutch, star washer and axle proceed as follows:

1. Screw N25 r-h cone/clutch onto the right hand (slotted) end of the axle. Clamp the axle vertically, left-hand end uppermost.

2. Drop N22 compound planet cage and driver and N34 r-h ball ring/drive sprocket assembly over the axle, drive sprocket down.

3. Observe the level of N197 sliding pinion teeth relative to the upper face of the internally toothed ‘clutch’ of the compound planet cage. The r-h cone/clutch is correctly adjusted on the axle when the sliding pinion teeth are flush with the internally toothed clutch of the compound planet cage (Fig. 4).

(If the r-h cone/clutch is not screwed on far enough, the fixed pinion could engage with the internal clutch teeth and probably lock the hub. If the r-h cone/clutch is screwed on too far, the sliding pinion might not be pulled far enough along the axle to engage high gear.)

4. Screw the r-h cone/clutch along the axle until correct alignment is achieved, fit the star lock washer and hold it in place temporarily with a spare axle nut.

5. From this point on assembly is the reverse of the dismantling procedure. When refitting N152 brake plate and arm be sure to align the actuating peg on N153 brake lever with the corresponding recess in N150 brake cone and remove the temporary axle nut that is retaining the star washer on the right-hand end of the axle.

The information provided here is presented in good faith, it worked for me but is not warranted – please use this information at your own risk.

Acknowledgements
Tony Hadland, The Sturmey-Archer Story, 1987.
Norman Richardson, for help and advice.
This article first appeared in The Boneshaker, journal of the Veteran-Cycle Club, Number 213, Volume 22, Summer 2020. It is reproduced with the kind permission of the club and of the article’s author, Peter Fuller.

Converting the Sturmey-Archer FW 4-speed hub into a 5-speed

NB: It is important to note that these instructions were written in the mid 1980s. Many items that were then current or easily available may no longer be so. The article is based on Appendix B of The Sturmey-Archer Story by Tony Hadland, published in 1987 by John Pinkerton.

Converting an FW into an S5/2

By far the easiest way to convert an FW to five-speed operation is to obtain a complete axle assembly for the S5/2 (HSA 329, HSA 330 or HSA 331, depending on axle length). This comes ready assembled, complete with sun pinions, dog ring, axle key and associated springs. The FW is merely rebuilt around the S5/2 axle assembly.

This conversion offers a gear which is virtually identical to the current five-speed hub. In the past Sturmey-Archer disapproved of five-speed conversions but, at the time of writing, the company is prepared to issue a list of the necessary parts for rebuilding FWs around S5/2 axle assemblies. They also market a retro-fit list consisting of the complete S5/2 internals and accessories for fitting into an FW shell, or an AW shell made before April 1984.

Converting an FW into an S5 (original pattern)

It is also possible to convert four-speeds to the original S5 style of operation; this involves a push rod in the left end of the axle, rather than the toggle chain used in the S5/1 and S5/2. The following conversion instructions for the FW were written by Denis Watkins of Castle Bromwich, after the discontinuance of the S5 and before the introduction of the S5/1.

1. The FW is really a five-speed hub in which, to permit its control with only one lever, only four speeds are used.

2. The extra low gear of the standard FW is brought into play by pulling the two sun pinions K409 and K408 to the right such that the dogs on K408 engage with the axle dogs.

3. If, when the FW is in top, it were possible to put K409 and K408 into the same position as in 2. above an extra high gear would be obtained.

4. To obtain both extra high and extra low, movement of K409 and K408 must be controlled by an additional lever. This can be done as follows.

5. Compression spring K8l3B is not required and must be removed.

6. Axle key K526A must be replaced by axle key K526 (used in AW).

7. Coupling/indicator rod K807ZA must be replaced by the type used on the AW.

8. Replace axle key K402 by a further axle key K526 and file ends of latter flush with surface of pinion sleeve K406.

9. Remove indicator rod K804 (K804A) and replace by a suitable push rod with end threaded to suit axle key K526. This is the only real difficulty. It is possible to use the rod portion of K504AZ (indicator for AW with long axle). It might be better to cut the outer end off an AW indicator rod and have a bit of similar rod welded “end on” to provide a total length such that, when the rod is pushed in to move K408 into engagement with the axle dogs, the outer end of the rod is flush with the end of the axle.

10. The push and release of the rod is conveniently controlled via a bell crank. Shimano have a very nice bell crank arrangement on their three-speed hub. Unfortunately it is threaded for a standard 3/8” (9.5mm) axle and there may be insufficient metal to permit drilling and tapping to Sturmey axle size.

11. A very important point; in early versions of the FW, K408 was made with parallel dogs. This is OK for conversion. Later versions of the FW had these dogs chamfered on the one face to facilitate engagement. These are unsuitable for conversion (unless an old type K408 can be obtained) as, if attempted, it will be found ‘ratcheting’ occurs in extra high gear and no drive is possible.

With regard to 11. above, the later FWs can also be converted if the larger sun of an S5 (HSA 269) or of an S5/1 (HSA 317) can be obtained. Of course, Sturmey-Archer produced a bell crank and push rod for the S5 (HSJ 679 and HSA 297 or HSA 288) but these are no longer available. The design of the bell crank evolved through three versions; plastic, pressed steel and machined steel. The latter seems to have been the most reliable. Some riders replaced the push rod with a modified flat-headed nail for smoother and more reliable operation.

An alternative to the bell crank was devised by Jack Lauterwasser. The push rod is made from a section of 12 gauge spoke and protrudes from the axle end by about 20mm. Threaded onto the external end of the push rod is a brass bush (made from a solderless nipple), drilled to permit the control cable to pass through freely at 90 degrees to the rod. An oversized tear-drop shaped brass washer is fitted to the wheel axle, with the pointed end of the washer pointing 180 degrees away from the cable fulcrum clip. The pointed end of the washer is cut out to house a solderless nipple, fixed to the control cable.

When the control cable is tightened, its far end cannot move because it is anchored to the tear-drop washer. The cable therefore straightens itself and, because it passes through the end of the push rod, pushes the rod into the hub, thus shifting the suns. The system works very smoothly.

The cable anchorage cut out, being keyhole shaped, permits quick release of the cable, merely by depressing the push rod whilst unhooking the cable end. Because the cable end is fitted with a solderless nipple, the push rod remains attached to the cable – with the bell crank system it is fairly easy to lose the push rod. The biggest disadvantage with this system is the risk of accidental damage to the exposed end of the push rod.

The Lauterwasser left-hand cable device

A somewhat similar system was devised by Mr P. Pottier of London during the 1950s. He used a Sturmey-Archer toggle chain, the end of which was riveted to the pointed end of the tear-drop washer; the chain passed through a steel bush push-fitted onto the end of the push rod. The control cable was attached to the toggle chain in the usual way; hence, when the cable was tightened, the chain moved the push rod further into the gear.

Non-Standard Controls for the S5

Many riders using the S5 type converted four-speeds use a derailleur lever for the left changer. This gives good ‘feel’ to the change (which, unlike that of the S5/1 and 2, is not designed to cope with crash changes) and reduces the need for cable adjustment.

Some riders advocate use of a derailleur lever also for the right hand changer; a practice greatly disapproved of by Sturmey-Archer because of the ‘no gear’ slip position between high and normal gears.

The Californian cycle engineer, Ernest Rogers, devised a Duo-Trigger Shifter for five-speed hubs. This consists of two of the metal three-speed triggers (not the current bulbous plastic type) bolted one on top of the other, the clamp of the top trigger body having been first removed. The effect is somewhat similar to the triggering arrangement on a double-barrelled shotgun.

New hub and bracket gear tables

You may have seen elsewhere on this site (in the comments on John Allen’s hub gear table in the Gears section) that Wiel van den Broek has created some very useful Excel spreadsheets for gearing choices involving hub gears and bracket gears. You can enter the tyre format, chainwheel and sprocket sizes and instantly compare the results given by different gears.

The gears covered range some more than 100 years old to others that are in current production. There is a metric (distance travelled per pedal rotation) chart and a gear inches chart (equivalent direct drive wheel diameter), both of which you can download from here: http://fietssite.jouwweb.nl/downloads

Many thanks to Wiel for creating these spreadsheets.

Tony

Sturmey’s right-hand ball rings: are you losing the thread?

Some instructions for disassembling Sturmey-Archer gears include a mysterious statement such as this:
“Next, unscrew the right-hand ball ring but because it has a two-start thread and must be replaced in its original position, that position must be marked. String or adhesive tape may be attached to the spoke nearest to the letters ‘SA’ which are stamped in one of the notches on the ring.” (From the 1956 Master Catalogue, sub-section 4, page 15, paragraph 1.)
The reason for replacing the right-hand ball ring in the same position is as follows. If the ring is screwed back in the alternative position, 180 degrees out from its original position, there could be some slight distortion of the completed assembly, due to a very slight difference of alignment between the hub shell and the ball ring. Whilst not noticeable at the hub end, it can result in the rim being slightly out of true. (The longer the spokes, the more the discrepancy is amplified.) So the precaution is in order to avoid the possible need to re-true the wheel.
This matter is not well documented but the rare 1992 Sutherland’s Handbook of Coaster Brakes and Internally Geared Hubs makes the point clearly. To facilitate correct re-assembly, Sutherland’s advises marking the ball ring at the point nearest the lubricator, rather than attaching tape or string to a spoke.
The reason for the two-start thread is to facilitate screwing the ball ring in relatively quickly, while having a stronger mechanical connection than an equally fast single-start thread would offer. For a given screw pitch, a two-start thread will screw in twice as fast as a single-start thread.
Tony

How to repair old Sturmey-Archer hubs

Instructions for a wide range of Sturmey-Archer hubs from 1902 to 2001. Includes the original 1902 3-speed, the type K series of the 1920s and 30s, the T and TF 2-speeds, the ever popular AW, the SW, SG, SB, AB, AG, TCW, AM, AC, ASC, FW, FG, FM, FC, BR, GH6, S3B, S3C, all 5-speeds, the Columbia 3-speed, the BSA 3-speeds (based on a Sturmey-Archer design) and the hubs in production when Sturmey-Archer ceased to be British-owned in 2001. Also included is information on the DBU and FSU accessories for use with hub dynamos. The files are in Adobe Acrobat format, making them zoomable and easily printable. (Content last added 21 June 2016)

In the beginning
1902 3-speed

BSA 3-speeds
Includes Jim Gill’s material on the rare split-axle versions

K series 3-speeds (K, KS and KSW)
An 18-page PDF file that includes Jim Gill’s analysis of the type K, design changes during its production run, cutaway drawings, Jim’s simplified instructions for dismantling and re-assembly, and S-A’s parts lists for 1925 and 1935.
K series S-A hubs

K series 3-speeds with drum or coaster brakes (KB, KC and KT)
A 13-page PDF file including Jim Gill’s description and analysis of the type KB 3-speed and drum brake, and S-A’s 1937 maintenance instructions and parts list.
Type KB 1937

A five-page PDF including Jim Gill’s description and cutaway drawing of the type KC 3-speed and coaster (back-pedal) brake, plus S-A’s 1925 parts list, Jim’s dimensioned drawing of the hub shell and his handwritten notes on (and sketches of) the type KC.
Type KC

A single page PDF showing S-A’s exploded drawing of the type KT 3-speed and drum brake for tandems. Also included are details of the special brake lever fittings.
Type KT

S-A 1930s drum brakes without gears (BF, BR, BRT and BFT)
A two-page PDF showing cutaway drawings of the 1932-36 versions of the type BF and BR brake hubs.
Type BF & BR 1932-36

A nine-page PDF including S-A’s 1937 maintenance instructions and parts list for the BF and BR hubs.
Type BF & BR 1937

A four-page PDF with cutaway drawings of early and later versions of the BRT and BFT tandem drum brakes.
Type BRT & BFT 1936-41

From the 1956 Master catalogue
Fitting and adjustment

Use and maintenance

Fault finding

General dismantling

Individual dismantling

Inspection

General re-assembling

SW wide-ratio 3-speed
(See also Brian Hayes’ paper)
SB wide-ratio 3-speed/hub brake

SG wide-ratio 3-speed/Dynohub

AW wide-ratio 3-speed (see below for later AWs)

AB wide-ratio 3-speed/hub brake

AG wide-ratio 3-speed/Dynohub

TCW wide-ratio 3-speed/coaster

AM medium-ratio 3-speed

AC ultra-close-ratio 3-speed

ASC fixed-wheel 3-speed

FW wide-ratio 4-speed
FG wide-ratio 4-speed/Dynohub
FM medium-ratio 4-speed
FC close-ratio 4-speed
BF & BR hub brakes
GH6 Dynohub
Dry Battery Unit & Dynohub wiring

Other Dynohub & Filter Switch Unit wiring information
FSU circuit diagram and notes
Wiring diagrams

Instructions from various dates, 1960s – 2001
S3B 3-speed with small-diameter hub brake
S3C 3-speed coaster
S5 5-speed
S5/1 5-speed
S5/2 and Five Speed Alloy 5-speeds
S52 1988 modifications
5 StAr and 5 StAr Elite 5-speeds
Columbia ‘no-slip’ 3-speed (Jim Gill’s documentation)
AB/C & BF/C 90mm hub brakes
AW 3-speed
AWC 3-speed coaster
AT3, VT and ST Elite hub brakes
Sprinter 5-speed hub and Sprinter 5-speed Elite 5-speed hub brake
Sprinter 5-speed coaster
Sprinter 7-speed hub & Sprinter 7 Elite 7-speed hub brake
Sprinter 7-speed coaster
Steelite SBF, SBR & SAB hub brakes

Triggers & Twistgrips, 1950s & 1960s
SA 1951 trigger instructions
SA 1956 trigger instructions
Twistgrip parts c.1966
Auto Twistgrip service instructions c. 1969


All information provided here is done so in good faith. It is as written by the original authors and has not been modified by Tony Hadland. No responsibility can be accepted for any loss, damage or injury of any kind sustained for any reason arising therefrom. Our thanks go to Sturmey-Archer Limited and Jim Gill for permission to reproduce their material.

Esoteric info for Sturmey freaks

The first seven of the following files provide amazingly detailed information on Sturmey-Archer hubs, from the earliest models to the present day. They were compiled by English engineer and hub gear enthusiast, the late Jim Gill. Although some of the material was originally published by Sturmey-Archer, the vast majority is Jim’s own work and has never been published before.

Also provided is John Fairbrother’s simpler approach to fixed-wheel conversions. John is an engineer and bicycle restorer based in Hampshire, England.

The files are in Adobe Acrobat format, making them zoomable and easily printable, page at a time.

Epicyclic Gears – some theoretical considerations
Engineer and hub gear enthusiast Jim Gill explains how various hub gears work. Includes zoomable diagrams.
21 pages

Sturmey-Archer Hubs – reference tables
Zoomable dimensioned drawings and tables of pawls, drivers, axle keys, pinion pins, gear teeth, ballcups, hub shell dimensions, indicators and more.
14 pages

Sturmey-Archer Hubs – axle charts
Zoomable dimensioned drawings of axles for Sturmey-Archer hubs.
26 pages

Sturmey-Archer Hubs – cone charts
Zoomable dimensioned drawings of cones for Sturmey-Archer hubs.
7 pages

Sturmey-Archer Hubs – spring charts
Zoomable dimensioned drawings of springs for Sturmey-Archer hubs.
5 pages

Sturmey-Archer Hubs – triggers
Zoomable dimensioned drawings of triggers for Sturmey-Archer hubs. Includes how to convert triggers for use with fixed-wheel hubs.
5 pages

Jim Gill’s fixed hub conversions
Jim Gill’s compilation of how to convert a 3-speed to 2-speed fixed-wheel and how to convert 4-speeds to 3-speed fixed.
8 pages

Jim Fairbrother’s fixed hub conversions
Modifications to Sturmey-Archer hub gears to produce fixed wheel gears
Engineer John Fairbrother outlines another approach to fixed-wheel conversions.
2 pages

Fixed hub trigger conversion
Modifications to Sturmey-Archer triggers for use with fixed wheel gears

More good stuff from Jim Gill.
2 pages

Elegy for Sturmey-Archer

Vernon Forbes of Columbia, Missouri
on what went wrong during S-A’s British years

I felt a great sense of loss when I heard of Sturmey-Archer’s closing in 2000. I remember sitting for a long time after I heard the news, feeling numb. I had sold, repaired, championed and ridden Sturmey-Archer gears for 21 years. The first shop I worked at was a Raleigh shop. They hired me because I could overhaul Sturmey-Archer hubs. They had all the many internal parts for several models of Sturmey-Archer gears in a wall of 5″x 6″ metal drawers. Small parts were in a case of 1″ x 2″ plastic drawers. Such a vast collection of ancient artifacts bore mute testament to a long and fine tradition of strength and durability that stretched to the beginning of the last century. I used to say the popularity of derailleur gears was little more than a fad in efficiency.

Sturmey-Archer’s Strengths

Derailleur bikes then were relatively flimsy and in need of constant maintenance to keep them working. Ten speeds were designed after Tour de France bikes. If cars were designed the same way they would all look like Formula One racing cars. Derailleur bikes, like their Tour de France counterparts, were not user friendly. Cyclists then had to switch between touch and sound modalities to “find” their gears. Even the most expensive derailleurs required careful installation and bicycle with a straight frame and chainline. Mechanics would carefully position and skilfully bend the front derailleur cage with pliers. Even then it could not handle more than a relatively narrow range of high gears in the hands of someone who knew how to perform what Frank Berto described as the “overshift-and-correct” shifting drill. In writing the history of derailleur chain gearing (Berto, et al., 2000), noted author Frank Berto described the remarkable craftsmanship of a Campagnolo derailleur saying “it will shift lousy forever”.

The metaphor of a derailleur bike being like a high-strung high-performance race car pushing the envelope of technology was viable then. Bicycles were like radio in the forties, recorded sound in the fifties or cameras in the sixties. Bicycle mechanics were like microscope repairmen.

By comparison, Sturmey-Archer (S-A) gears were user friendly and virtually maintenance free. From among the hurley-burley of designs and compatibility problems Sturmey-Archer emerged as a golden standard. Its design rarely changed and parts had always been available. The most desirable feature of S-A gears was ease of shifting. Instead of shifting while steering with one hand you just flicked a trigger on the handlebars. S-A gears were safe, simple and reliable.

This reputation eroded as Suntour and Shimano began making derailleurs so reliable you didn’t need repair parts. Power shifters, bar-cons, and self-adjusting front derailleurs began closing in on the superior simplicity of use previously dominated by S-A. In 1985 Shimano optimized rear derailleur geometry and introduced indexed shifting (Berto, et al., p.260). The final blow came in 1989 with SRAM’s twist grip for derailleurs (Berto, et al., 2000, p. 263) just like those S-A had been producing since 1961. Suddenly, all I could say to potential customers was that S-A gears were indexed shifting when indexed shifting wasn’t cool.

Losing their advantage of being both user friendly and low-maintenance in the face of a rapidly improved derailleur a fair comparison could now be made. Having a weak engine, bicycles need higher gears that are closer together and lower gears that are further apart. Hub gears have higher gears that are further apart and lower gears that are closer together (see Figure 1 below); the exact opposite of what is needed (van der Plas, p. 161). This is just how hub gears work. Derailleur gears, with their ability to match the limitations of human effort, were superior in this regard.

Gears graph
Figure 1: Hub and ideal gearing


At least in America, few people seemed to know that the sprocket size on an S-A hub could be changed so that a larger sprocket with more teeth gave lower gears. The gears Raleigh used on their Sports model came with an 18 tooth cog that gave a normal of 66.4 inches (for metric users, a ‘development’ of 5.3m) with a low of 49.8 (4.0m) and a high of 88.6 inches (7.1m). People buying a bike thought that three-speeds “didn’t have enough gears to climb hills and were too hard to pedal.” Raleigh Sports bicycles weighed 36 lbs and came with fenders and needed lower gears. The gears it came with were too high. I remember I used to routinely swap-out the cogs on the over-geared Raleigh Sports. If Raleigh had specified hubs with 22t cogs that would have given the ideal gearing with a medium of 54.3 inches (4.3m) with a low of 40.8 inches (3.3m) and a high of 72.5 inches (5.8m). As a result of being over-geared hub gear owners found themselves shifting often between normal and low with high gear being “way out there”. Probably more than everything else combined, this one detail made most customers prefer to buy ten-speed derailleur bicycles.

The only explanation I ever heard for why Raleigh over-geared their three-speeds was that cyclists used to turn higher gears with longer cranks at lower RPMs. Still, it never made sense.

Mountain Bikes

Along about this time another seemingly unrelated trend was to unmask one of S-A’s characteristics as a defect: gear slip. Ten-speeds were built for a full-tuck riding position and were awkward to ride. The only accommodations made for women was to tilt the saddle nose down 2-3 degrees. To people with chronic back problems I repeated the findings by French physicians that the full-tuck riding position was actually good for your back. To those with carpal tunnel problems I recommended gloves. For men with prostate problems I recommended a leather saddle. Like the ordinary bicycle, or penny farthing it replaced, the derailleur bicycle had evolved to serve a narrow bandwidth of young, athletic, male customers. The bicycle was difficult to ride and maintain.

The emergence of mountain bikes changed all this. With an upright position anyone could easily ride them, and with an emphasis on durability they brushed the flimsy ten speeds aside. S-A gears could not be used for off-road riding for two reasons, the foremost of which was gear “slip”. If the hub is not in adjustment and you are riding in either normal or high, the gear can unexpectedly go into a “no gear” intermediate position between the gears. When it does this the gear suddenly disengages itself under load. Gear “slip” had long inhibited “honking”, or riders getting out of the saddle to pedal up hills because there is always the chance that while you are standing on the pedals it could suddenly slip out of gear. Since mountain biking required out-of-the-saddle pedaling for climbing hills S-A gears were not an option.

Another problem was gearing; S-A recommended that the rear sprocket be no larger than 22 tooth be used (presumably with a 46 tooth chainwheel) giving a 54 inch (4.3m) normal with a low of 41 inches (3.3m). Lower than this and, and as Frank Berto once said “presumably, the hub would grind itself into pieces the size of tooth fillings”. Mountain biking needed these lower gears, especially since honking was not possible. Think about it: you couldn’t use ultra-low gears but you also couldn’t stand up to pedal. This effectively shut S-A gears out of mountain biking, limiting them to road use.

Because the bikes they provided for road use were all hopelessly over-geared the picture of S-A’s inevitable obsolescence is more understandable. What is most curious is that S-A hubs had been “slip-free” since the 1904-1937 “X” model hub. Why didn’t they just bring back “slip-free” hubs when mountain biking became popular and why did they ever quit making such hubs in the first place? The answer has to do with the series of management companies that ran S-A.

Sturmey-Archer’s Origins

From the beginning S-A was owned by Raleigh Cycle Company. Frank Bowden, Raleigh’s founder, was in the process of building what was to become the world’s largest bicycle manufacturer when he was approached by William Reilly, a poor Irishman, about a three-speed hub he had just invented. In 1902, in a series of legal maneuvers he swindled William Reilly out of the patent rights and got rid of him (Hadland, 1987, p.52). Reilly died in obscurity on a curb in Stockport, near Manchester in about 1950 when he was 83 (Hadland, 1987, addendum); S-A was thus born with Raleigh was the management company.

A Lack of Innovation

The original 1902 hub Reilly designed was a fixed-gear three-speed; you could shift gears but you couldn’t coast. It had an external freewheel threaded on, so you could coast. It had two “intermediate” no-gear positions between the gears to prevent simultaneous engagement of two “fixed” gears, wrecking the hub.

In 1904 the “X” hub replaced the original design. It didn’t need an external freewheel to coast because inside the hub it had three sets of pawls, one set for each speed. If simultaneous engagement of normal and low gears occurred the normal set of pawls was turned faster than the low gear pawls and over-ran them. If there was simultaneous engagement of normal and high the high gear pawls over-ran the slower normal gear pawls. A loose cable gave low, so if the cable broke the hub stayed in low. Designed by the inventor of three-speed hubs, William Reilly, BSA, continued to produce this hub for their bicycles until 1955 when they were acquired by Raleigh who discontinued Reilly’s hub. Bowden took over management of S-A in 1909 after he got rid of Reilly.

Bowden was a brilliant businessman in the process of building a bicycle manufacturing empire. He was not as interested in innovation as he was holding down costs. Raleigh allowed S-A to only just barely survive. Raleigh didn’t want anything but over-geared three-speed hubs and as long as that’s all they produced they didn’t care. The creative genius of S-A engineers was reduced to cutting costs to extend their tiny budget. I always imagined the R&D department as something like Hitler’s bunker.

WWI, production and design problems plagued S-A from l9l4-1918, when they designed the K model hub. This got to the market in 1921. S-A designed it as a cost-cutting measure so that if the cable broke the hub was stuck in high. This was a step backward. For another thing the K hub had only two sets of pawls. One set was used for both high and normal speeds and the other set for low. In high gear the high/normal pawls were fed after being multiplied by the planet gears for high gear. In normal same set was fed directly without being multiplied by the planet gears. In both gears the low-gear set was over-run. For low the sliding clutch “tripped out” the high/normal gear pawls unmasking the previously over-run low gear pawls. This method of “tripping-out” pawls prevented normal and low from being simultaneously driven. There was a danger, however, of simultaneously engaging normal and high. This was prevented in the following way. The fronts of the six clutch arms were square to fit against tabs on the inside of the gear ring for normal. The backside of the six arms of the sliding clutch were ramped so that if both normal and high were simultaneously engaged the gear ring was driven by the high gear. The drive of the faster turning gear ring drove itself into the ramps on the backs of clutch arms and pushed the clutch into full engagement with high. While clutches were expensive to make and tended to wear out there was no “no-gear” position and the hub was always in gear. In 1937 the K hub was replaced by the AW model with the infamous “no-gear” position (see Figures 2-7 below). AW clutches had four unramped arms and were cheaper to produce (Hadland, 1987, p.97). Like the K hub it replaced the AW used two sets of pawls and tripped out the normal/high set to unmask low, preventing simultaneous engagement of normal and low speeds. To prevent simultaneous engagement of high and normal AWs had a “no-gear” intermediate between them to keep them separate (Hadland, 1987, p.97).

Fig 2
Figure 2: This and figures 3-5 show how a hub gear works. This shows the sprocket fitted to the driver. The gear ring and ball cup are cut away to show how the arms of the driver fit over the clutch. The planet gears all spin around a fixed central sun gear on the axle.

Figure 3: High gear. The driver and ball cup have been removed and the gear ring cut in half to show the clutch, which engages the planet pints protruding from the planet cage. As the planet gears turn around the central stationary sun gear (not visible), the gear ring is turned 33% faster.

Figure 4: Normal Gear. The clutch has been raised and its arms engage tabs inside the gear ring, which is therefore driven at the same speed as the driver.

Figure 5: Low Gear. The clutch is fully raised. It still engages the tabs of the gear ring but it also trips out the high/normal pawls so that they no longer engage the ball ring. The gear ring thus turns at the speed of the driver and the planet cage now turns 25% slower and drives the hub through the low gear pawls visible in Figure 2.

Figure 6: This shows the “no-drive” position between normal and high gear.

Figure 7: This shows the principle of the ramps on the back of the clutch arms of the “K” hub. If the clutch engaged normal and high gear simultaneously, the gear ring tabs would run into the ramps and force the clutch down fully into high gear and away from normal gear.


It was not so much that S-A was unable to lead the field in market development as it was unwilling.

S-A continued to patent two additional different “no-slip” designs in 1948 (Hadland, 1987, p.120) and 1971 (Hadland, 1987, p.157). Raleigh patented their own “no-slip” design in 1972 (Hadland, 1987, p.154). Raleigh blocked production of all these.

Another example of S-A’s inability to lead in product development is hub brakes. Consider the popularity of disc brakes now. I recently opened a bicycle mail order catalogue and counted no less than six different kinds of disc brakes. When downhill racing became popular S-A announced they felt the disc brake “had no future in cycling” and stuck with drum brakes. In l985 when S-A said their gears were not strong enough for mountain biking (Hadland, 1987, p.168) it was reminiscent of the 192Os and their making similar disclaimers that their gears were not strong enough to be used on tandems. While S-A had produced a tandem three-speed in 1934 (Hadland, 1987, p.90) but they deleted it in 1941 (Hadland, 1987, p.189), giving derailleurs a niche market in which to get a toe-hold after WWII.

As the world changed the circle of Victorian Engineers at Raleigh who seemed to run S-A rigidly refused to acknowledge the world had changed since l9O4. They continued to make gentlemen’s gears for Edwardian cyclists. They probably figured that mountain bikes, like tandems, were just a fad.

Even in “gentlemen’s gears” they shunned innovation. Just like the “no-slip” three speed, S-A continued to patent innovations that Raleigh withheld from the public. Henry Sturmey patented a five-speed in 1921 and S-A continued to patent different designs of 5-speeds in 1940 (Hadland, 1987 p.111), 1973 (Hadland, p.155) and a 6-speed in 1954 (Hadland, p.130). Production of 5-speeds did not begin until 1966 (Hadland, 1987, p.146.); a 45 year interval.

S-A was starved and their resources plundered while Raleigh continued to grow. With over 7,000 employees in 1960 Raleigh was purchased by Tube Investments (TI), a manufacturing conglomerate that made everything from industrial tubing to several highly successful kitchen pans (Hadland, 2000). S-A had a new management company to run it and it was Raleigh’s turn to be managed. TI continued Raleigh’s regressive practices of plundering profits and blocking progress but had their own cruel twist about the mouth. Under TI’s management, Raleigh didn’t bring out a children’s hi-rise, or Stingray, bicycle until the demand in America was over. During the 1960s, Alex Moulton designed a small wheel bicycle and offered to sell it to Raleigh. After rejecting his offer Alex Moulton made them himself (Hadland, 2000). The bicycles proved wildly popular and Moulton bicycles quickly became Raleigh’s #1 competitor (Hadland, 2000). Raleigh delayed bringing out a BMX bike until it was too late to develop market share and got such a late start in mountain bikes (1984) they lost millions (Hadland, 2000). Now it was Raleigh’s turn to have its hands tied.

One outstanding example of the way TI prevented innovation involved the geared Dynohub. The Dynohub was a hub that contained a generator that powered bicycle lights. S-A had patented a geared Dynohub in 1967 (Hadland, 1987, p.147). While the generator turned as fast as the wheel a “geared” Dynohub generator was designed to turn faster than the wheel and generate more power. The Dynohub had been in continuous production since 1945 (Hadland, 1987, p.167). TI blocked bringing out the geared Dynohub. Rather than coming out with an updated more powerful model to stimulate sagging sales, it was cheaper to discontinue it and the Dynohub was withdrawn in 1984 as well as its battery-takeover option (Hadland, 1987, p.133). This was too bad because generator hubs are currently made by three different companies; Schmidt, DT and Shimano.

Another example of cost saving measures was the indicator chain coming out of a hollow axle, a feature of all S-A hubs. Because you couldn’t use a quick-release it had all the disadvantages of both a quick-release hollow axle and a solid axle; without the strength of a solid axle it was weak like a hollow axle but without the convenience of a quick-release. S-A patented a solid axled 7 speed in 1974 (Hadland, 1987, p.157). The 1974 patent on the solid axled 7 speed had expired by the time Shimano began producing S-A’s designs and producing gears with solid axles. By the time S-A closed Shimano had a solid axled 4 and 7 speed, Sachs had a 5, 7 and 12 hubs that used indicator chains and Rohloff had a 14 speed in both solid axle and quick-release versions, before S-A finally came out with the solid axled 7 speed they had patented 20 years before.

As early as 1984, as Mountain bike sales exploded, S-A, under TI, produced a “no-slip” three-speed for Columbia Bicycles in America that was not released to the general public. It had three sets of pawls and a ramped clutch. In 1984 Raleigh still didn’t have a mountain bike. By Feb. 1987 they had made 60,000 hubs for Columbia (Hadland, 1987, p.167). They were still in production in 1997 though they had not been released in the United Kingdom (Read, p.114). Their steadfast refusal to issue these to the general public is but one of many decisions that led to Sturmey-Archer’s increasing obscurity.

Moreover, three speeds, for all their faults, actually cost slightly more in America than their lighter ten-speed counterparts in the late 70s. For example, the Raleigh “Record Ace” introductory ten-speed was $265 in 1979 in the USA. By comparison a 3-speed Raleigh Sports cost $285. While the emerging mountain bikes still cost well over $600 prices were shortly to begin dropping rapidly as they exploded in growth.

Though British-made Raleigh imports to the U.S.A. stopped in 1981 there were a lot of three-speed bicycles still around and I could still find work as a Sturmey-Archer specialist.

About this time Sturmey-Archer was forced to discontinue rather than update a number of products which had long been in production such as the Dynohub with its battery take-over. They redesigned the drum brake which they offered in a bewildering array of materials and finishes.

Design Problems

The road to obscurity had not only to do with mountain bikes and S-A’s withholding from the public the same improved designs they provided to manufacturers but also a history of defective designs for products they did release to the public that betrayed the loyalty of even the most die-hard customers.

In 1980 I convinced a shop to order a couple of 5-speed hubs. Someone heard we had them and drove fifty miles to buy one. But he kept bringing it back saying it “slipped” out of gear. We ended up giving him his money back. A few months later we got a notice from S-A that the hub had a “faulty” spring. It was too late because no bike shop in town would take the chance on selling five-speed hubs. Some time later I found the shift levers it came with were also “faulty”.

I remember being delighted when S-A came out with an aluminum-alloy-hubshell five-speed hub in 1983. This was withdrawn in 1989 when it was found that pieces of the gears would burst through the hub shell (Read, p.83). Though I never saw this it must have been spectacular to see. The 5-StAr hub (the capitalized “A” playing on the first two letters of the words “Sturmey” and “Archer”) was introduced in 1991 but was withdrawn two years later because it tended to break axles. Though these happened on a relatively minor scale they had the effect of alienating the finicky and touchy market that cyclists are. S-A came out with a series of triggers that, with their increasing reliance on injection-molded plastic, bore an uncanny resemblance to a child’s play-toy. No serious cyclist would even consider putting such ugly junk on an expensive Reynolds 531 frame.

The real tragedy of this is that S-A didn’t have to fail. Recent research by Frank Berto and Chet Kyle indicates that run-in and well oiled Sturmey-Archer hubs are 91.8%-95.6% efficient compared to a Shimano derailleur’s 86.9%-95.9% efficiency (Berto & Kyle, 2001).

In 1979 S-A completely dominated the market. The history of bad design choices has its roots in some of their earliest designs. Before 1922 if a cable broke on a S-A hub it was locked in low (Hadland, 1987, p.74). Under Frank Bowden they redesigned it in 1922 so if the cable broke the hub was stuck in high. They brought out the “no gear” position in 1937 because it was cheaper to make. In 1954 they substituted the AW three-speed design with the ill-fated “SW” model three-speed (Hadland, 1987, p.134) with springless crescent-shaped pawls. How this hub got into production is curious because it never worked and slipped in every gear. What is most surprising is that it took them three years to withdraw it! I don’t know if they replaced all the defective hubs they sold but I don’t think they did.

At the time I first started working in a bike shop Sturmey-Archer was owned by Tube Investments which also owned Reynolds, Raleigh and Brooks. Like a ship breaking up on its way to the bottom Tube Investments sold Raleigh USA to Huffy; the largest manufacturer of junk bicycles in America in 1982. Anticipating a corporate sell-off, Derby, an American management firm was formed by a wealthy American tax attorney expressly for the purpose of acquiring old Raleigh holdings as they were sold by TI (Hadland, 2000). Raleigh of England, Reynolds, Sturmey-Archer and Brooks came under the management of Derby, Inc. in 1987 (Hadland, 2000).

TI had pretty much ruined Raleigh/S-A. By the time TI was finished Raleigh went from employing 7,000 employees in 1960 to 700 in 1987 (Hadland, 2000). The factory was virtually the same as when they bought it, only more decrepit. Moreover, aluminum was the tubing of preference and Raleigh couldn’t do anything but make steel bicycles.

S-A had their resources plundered and development choked for 85 years by first Raleigh and then TI. Derby, their new owner, would eventually own Raleigh of England, Raleigh of America, Nishiki, Kalkhoff, Univega, Gazelle, CyclePro, Haro and Diamondback and be the largest manufacturer of bicycles in the world. Under Derby, S-A began innovating and was allowed to finally release their “no slip” three speed hubs, the ill-fated 5-StAr in 1991 and the solid-axled 7-speed hub to an optimistic public in 1995 (Read, 2003). Tragically, both these designs were defective and S-A had to issue replacements. In 1999, after twelve years of trying to undo the damage and upgrade the factory Derby quit trying. They sold the land Raleigh and S/A were on to the University of Nottingham and auctioned off Raleigh’s brand new laser cutting equipment and robotic machines. They didn’t know what to do with S/A’s buildings and patents and so they sold S-A and Brooks for the price of a three-speed hub (Hadland, 2000). The buyer was Lenark, a shady British management firm who had previously been investigated for fraud.

The law of supply-and-demand was never so cruel.

The end came abruptly. Shortly before my birthday, in October, 2000, the employees were called in, told that Sturmey-Archer was closed and they had ten minutes to get out. A year later I still had trouble accepting that Sturmey-Archer was closed, the workforce unemployed, the land sold to a university to train people for a future without jobs, the buildings knocked down and the machines put in a ship container for Taiwan where Sun Race, their newest management company was located. For me, S-A is gone forever.

Epilogue

S-A’s failure had its origins in 1904. What we are seeing is the dark fruit of greed. The greed that designed hubs for cyclists like the SW and the AW with its “no-gear” position was the same greed that sold the land S-A was on to a University. Greed and avarice do not serve society any better than they serve the needs of cyclists.

My own fortunes followed those of Sturmey-Archer’s. While I continued as a mechanic I was not hired as a Sturmey-Archer specialist after 1985. The bike shop I work in now is a Raleigh shop. It has one extra three-speed cable and one small plastic drawer labeled “Sturmey-Archer” containing a couple of frame fittings.


Annotated Bibliography

Berto, F. and Kyle, C., (2001), HUMAN POWER, #52. Summer, 2001. pp.#3-11. Though other articles have appeared measuring the efficiency of epicyclic gearing this is the most recent and possibly most carefully done.

Berto, F., Shepherd, R., and Henry, R. (2000), THE DANCING CHAIN, Self-pub., San Francisco. The definitive text on derailleur design and history. Imprimatur.

Hadland, T. (1987), THE STURMEY-ARCHER STORY, Self pub., s.l. The definitive text on Sturmey-Archer hub gear design and history. Nihil Obstat. Imprimatur.

Hadland, T. (2000), Raleigh in the last quarter of the 20th century. In the 11th INTERNATIONAL CYCLE HISTORY CONFERENCE PROCEEDINGS, A. Ritchie & R. van der Plas, Eds. Van der Plas publications, San Francisco, Calif., USA. Chronicles the confusing business dealings that led to Raleigh’s leaving England and Sturmey-Archer’s closing.

van der Plas, R. (1991), BICYCLE TECHNOLOGY. Bicycle Books. San Francisco.

Read, P. M., STURMEY-ARCHER: “THE END” AND “NEW BEGINNINGS”; (1902-2000 onwards) hub gear drawings, diagrams and parts lists, Fourth Ed., (1997), Self pub., Milton-Keynes. Peter Read has a business repairing Sturmey-Archer equipment. This massive tome is the definitive guide to repair each S-A design with many small changes carefully documented. It includes the many aftermarket improvements that Sturmey-Archer cognoscenti have developed over the years.

Acknowledgements

The author thanks Tony Hadland on whose research this article is almost entirely based and for his invaluable suggestions. The author also thanks David Gordon Wilson and Peter Read of Phoenix Hub Gear Repairs for their invaluable comments on earlier versions of this paper. The author is especially grateful to Marv Wells, in Columbia, Missouri for his expertise in preparing the images. You’re a good bud, Marv.

The Author

The author is a bicycle mechanic in Columbia, Missouri, U.S.A. You can contact him by email at dansemacabre.1347@yahoo.com or by paper mail at 1007 Grand Ave., Columbia, MO 65203-4025, USA or by telephone on + 573-442-1187

Figures and Text both copyright (c) by Vernon Forbes, 2003. (Minor revisions February 2012)

Hub gear ratio spreadsheet

John S Allen is one of the greatest technical writers about bicycle technology. He has recently produced an amazing spreadsheet of hub gear ratios, calculated from first principles. This reveals that, in some cases, the ratios quoted by the manufacturers are incorrect.

John says,

‘I felt the exercise to be useful because almost all the information I’ve seen about ratios gives decimal numbers. The actual ratios are fractions, many of which do not reduce exactly to decimals. Some numbers are given to only two places after the decimal point, not really as accurate as would be desirable. I also found incorrect rounding and in some materials I reviewed, transcription errors.’

Here’s a link to this uniquely useful spreadsheet.

Tony