How to repair old Sturmey-Archer hubs

Posted on by Tony Hadland

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.

69 thoughts on “How to repair old Sturmey-Archer hubs”

  1. I acquired an AB hub last year and have only just got around to cleaning it up. I knew it was pre WW2 but despite the engraving on the hub shell being faint and most of the chrome plate having gone leaving only some of the nickel, it appears to me to be engraved AB7. I am hallucinating or can this be correct ?
    Steve W, V-CC 5348

    1. Hi Steve,
      Many thanks for your email. No, you’re not hallucinating. The 7 indicates 1937 manufacture, the mid to late thirties being when interest in hub brakes was at its peak in the UK.
      Tony

      1. Thanks Tony, I had it in my mind that AB was not launched until 1938 but I assume that production started earlier. The screw on sprocket is very well worn but the hub appears to still work quite well and the brake linings still have some ‘meat’ on them also. It will go into my growing collection of SA hubs. Thanks for your help !
        Best Wishes, Steve

      3. Hi Tony
        Upon closer examination my 1937 AB hub differs in some ways from the exploded drawings that I have seen. It has a 6 prong selector and a two part indicator rod of a type that I have not seen previously – one end being spade shaped. Can I assume that I have KB internals in an AB hub shell ?
        Thanks, Steve

  2. A multiple-bicycle-owner in Amsterdam (Netherlands, yes), I landed here in search of a “How To Disassemble Your Sturmey-Archer Gear Hub”. I am very impressed with the well-organized library of directions PDFs pertaining to differences between the many varieties that appear to have been used by BSA/Raleigh through the years, most of which types I must say I had never heard of.
    I’ve got seven nigh immaculate Raleigh ladies’ bikes (which I’ve always preferred to their men’s counterparts, for their ease of mounting, comfort and elegance), one BSA, models varying from “Superbe”, “(Sports) Touring” to compact models, including one Shopper and then a type, possibly issued in Holland uniquely, not sure called “Family”. Years range from 1980 to 1986, roughly. Wheelsizes are 27″ (1x), 28″ (2x), 26″ (3x) and 24″(1x). All have 3-speed gears, most with drum brakes as well. I use all of my bicycles regularly, changing as the weather does. I like to keep them spotless.
    Now, my Raleighs rarely require repair other than changing a blown or worn tyre every once in a while. I am not a tech but smilingly carry out standard maintenance, you know, oiling and greasing the usual points, as well as making sure all nuts, bolts and screws remain cleanly turnable, yet correctly tightened and so on. It’s just fun. It is always a joy to take a rattle-free, shining, bicycle for its checkride, hear the whirring sound of the SA hubs when coasting, and hear and feel the gear shifter (the ‘trigger’) going throught its “like new” clicking motions as I shift gears (and especially up, with that added swift pull from the cable on the lever).
    Some guy I know was scrapping his own horribly-maintained mid-eighties Raleigh and I was lucky enough to catch him do it, knowing his SA gear hub, AB, was the only part of the heap in trouble-free shape and worth keeping. For me. So got his crooked rear wheel and now have to figure out a way to salvage the internal assembly from the hub. That’s how I got here.

    So, thank you very much for making those interesting “exploded view” drawings available. They will hopefully serve as a guide when taking my spanner to the job, helping me be prepared where of fiddly parts may jump out over my shoulder.

    My name is not really Ringo. Best wishes,

    Roy
    Amsterdam,
    Olanda.

  3. I think i have a S-A anomoly, or at least an intermediate version of a hub which has no extant documentation. It is a Steelite SAB 70mm with the brake cover plate marked 10-89, but the internals are not matching the documentation from the SA website for the 1987 Mark II, but also don’t match the diagrams and SA documentation LTE 146, for the hubs of the period 10-95 onward. The planet cage is a single item, with no seperable Gear support plate, and no Circlip, and the sun pinion pin cannot be removed, the clutch is of the type HSA 536, but the drive pawl arrangement is clearly HSA 472, with the driver assembly HSA 439 aslo present. It looks like an axle from a Mk II 1987, but with some parts from the 95 version. I guess the documentation Im after is LTE 124-1, but do you think i would ever find it?

  4. Tony,
    Wonderful to have found your informative Blog.I have been tormented by a couple of SW hubs as of late.
    The hubs are dated to 1956 and 1958 and are original equipment on Dayton Flyer and Royal York bicycles.
    Inquiries at local bicycle stores have been not helpful. The equipment predates most shop owners experience and they would rather replace it than repair it.
    When I inquired of Sunlite they were of equal assistance.
    I have down loaded the information on the SW hub and it appears to be just what I was looking for.
    i have another question that isnt covered. regarding the trigger shifter on the “Flyer”.
    The printing on the face of the shifter is upside down.
    I would think that would dictate the original position of the shifter on the handlebars.For the rider to read it, it would be on the left and below the front brake lever?
    Most every other trigger shifter I have seen was mounted on the right hand with the printing upright.
    Have you seen the seemingly upside down printing before?
    Thanks for your assistance…Dan

    1. Hi Dan,
      Glad you found the info useful. From about 1960 the orientation of the lettering on S-A triggers was flipped. Previously the assumption was that the trigger was mounted below the bar. The change of orientation reflected that above bar mounting had become the norm. In both cases the trigger would normally be on the right-hand side of the bar. So with below-the-bar mounting the rider would have difficulty reading the lettering, or seeing the indicator window that some triggers had up to about 1956.
      Hope that helps!
      Tony

  5. Great stuff. All in one place.
    I’m looking for info about spokes length used with typical raleigh 26 1 3/8 rim
    I dismantled two wheels with SA hubs – SAB3 and SBF – both 70mm drum brake. I have spokes etc. but when I measured length and compared to spokes calculator – its totally different… also rear spokes are all almost the same but there is 20mm diameter difference between left and right flange… (my bad that I mixed up spokes)
    I’m quite confused… (I do bicycle repairs – including wheel rebuild as a hobby)
    Thanks for any help

  7. I am rebuilding a TC for riding (not show or restoration). I do not understand how the K70, K71, K72 & K73 felt seal parts work, I do not have any K71s, and I know of no sources. Peter Reed’s compilation and description says that the K71 outer seal is part of the cone, but that is not how the NOS TC is built. That appears to have the seal retainer as a cup that presses over the hub shell (or left ball cup on a K). Nor do I know of any sources for K19 cones which do not use the felt seal. The oldbiketrader.com website says “closed due to ill health” and I believe that has been true for several years. However the metal shield from the K105 (and maybe HSA150) left dynohub cone will fit on the K506/HSA101 standard AW cone, and has the same diameter as the K19 shield. I believe the shield from a front dynohub cone of that era is also the same but that is untested. Any comments on whether this should work? Or other options? Has anybody made a version of the LB405/HSA102 hub dust shield insert that fits the K & T hubs so we can move to A series cones and seals (and use the A series right cone locking mechanism)?

    1. Hi Michael,
      Thank you for this and I note the correction in your following message. A 1930s KS and KSW parts list published by Sturmey-Archer describes K71 as “Dished (outer) Retainer Cap” but on the accompanying diagram it is not shown. However, the exploded drawing of the TC issued by Sturmey-Archer shows it immediately left of the hub shell/ball cup – but you’ve probably worked that out already. I don’t think I can shed any further light but you might like to contact Vince Warner at Colwood Wheel Works: https://colwoodwheelworks.co.uk
      He is much more ‘hands on’ than I am these days and if anyone knows where to get obscure S-A spare parts, it’s probably him.
      Cheers,
      Tony

    2. PS: K70 was a part used on types K, KS and KSW. As type K was the standard 3-speed for quite some time, it should be possible to find this part.

  8. Hi Tony,
    I am having some issues with first and 3rd gear on a 1948 FG 4 speed Dynohub, what would your thoughts be that is causing this issue?

  9. Hi Tony, I have an S5.2 hub in excellent condition from 1986, but the twin cable plastic thumb changer changer is broken, I have located a similar plastic changer but it’s for the 5 Star hub – the question is – do you think it will work with the S5.2 hub? Looking a picture of it the cables appear to exit from the changer on the opposite side of the housing body.
    Any thoughts or advise welcomed.
    Thanks and best regards
    Tony Maile

    1. Hi Tony,
      Thanks for your email. I have put your query to Alan Clarke at Sturmey-Archer who replies accordingly:
      “I think that it might work but actually I have never tried it or had this question before. Another possibility is to use 3-speed. The gear movements were the same as the AW, so a standard trigger control could be fitted on the right hand side and then the bike could be still used but now as 3-speed. In theory, it is also possible to fit a second trigger upside down) on the left and use two of the positions to change those gears.”
      As you probably know, the two-trigger approach was standard originally and you may recall seeing older 5-speed Bromptons thus equipped.
      Cheers,
      Tony

  10. I have an 1972 S3B (28 spokes with 55-mm drum brake) currently in London that I shall be rebuilding into a 1980s Bridgestone ladies bicycle here in Tokyo. I really need a dimensional diagram to accurately calculate the spoke length for ordering the spokes before the hub gets here. I have searched high and low but cannot find the data I need online. Can anyone point me in the right direction?

      1. Thanks Tony.
        I downloaded the manual and it has the S3C (coaster brake) but not the S3B (drum brake). They look very similar but the distance between lock nuts is 115 for the S3C but 120 mm for the S3B (about the only dimension I do know). This means the geometry from the lock nuts to flange centers and from flange centers to hub center will be slightly different to the values they give. The effective diameter of the rim is 494 so I tried calculating the SL for the S3C and it gives me 228 mm. Making slight changes/guesses for the longer 120 mm between lock nuts of the S3B gives me 227.2 mm so I guess 228 is what I need (both for a 2 crosses lace with 28 14G SS spokes)
        Hope I’m doing this right.

      2. I don’t have an example to hand to check but my recollection is that it’s very similar to an AW of the same period. But to make sure you’ve got it right, I would suggest emailing Alan Clarke of Sturmey-Archer (who runs their Heritage website). His email address is alan@sunrace.nl
        Cheers,
        Tony

  11. Hello Tony-
    I figured out what was wrong with my hub- thought youʻd like to know and provide a cautionary tale for others. I had the low gear pawls in upside down. I was sure I had them in right until I disassembled a NOS AW I have to compare with. Itʻs working perfectly now- I guess Iʻll wipe the egg off my face and go for a ride…
    Thanks for your help,
    Tim

  12. Hello Tony-
    I have a 1964 Moulton with an FW 4 Speed. Iʻve successfully disassembled and reassembled it in the past for servicing but this last time I ran into a problem that I canʻt solve. When I shift down to second or first I have no drive. Iʻve disassembled and reassembled several times and the problem appears to be that the clutch disengages the low gear pawls on downshifts. I have no idea why itʻs doing this now when it didnʻt before and I canʻt fathom what I may have done wrong. Any ideas?
    Thanks, Tim

  13. Is it possible to fix the front light (green color with chrome rim) of my restores raleigh superbe cycle.

  15. Hi Tony,
    Thanks for putting all this information together and making it available. I am rebuilding a KT6 from a Saxo tandem, and on taking it apart, the innards are not all correct. I hadn’t been able to engage 3rd year since buying it, and I wonder if it has been bodged. Can you advise me on how to get it back to three years? Thanks

    1. Hi Matt,
      Can you be more specific about what you think is not correct with the innards? For example, are certain bits missing or locked together?
      Cheers,
      Tony

      1. Hi Tony,
        Thanks for your reply. Having been through the parts, it seems that the insides are much the same as those in an AW. The axle is 6.25″ and has a pinned 20t sun gear and is blind like K751. There is no indicator, and no planet cage/spring, and the driver is 4 prong tapered, not 6 prong. The clutch is like an AW clutch. So although the shell is stamped Kt6, I wonder if it has been substantially rebuilt with AW innards.

      2. To correct myself, there is no cage support plate or spring (K45/6), and the planet cage is the same as K515 on an AT drawing as the pawls are sprung, and is not like a K15.

      3. Hi Matt,
        The hub has definitely been messed about with and it sounds as if most of the innards are not type K at all. All type K hubs have 6-inch long axles and none have blind axles. (They all have an indicator rod on the left side.) Although K driver prongs vary somewhat in shape, all drivers are six prong.
        Incidentally, although the type K clutch originally had a “no intermediate gear” (NIG) feature to prevent a no-drive gap between second and third gear, this could prove problematic in use. In 1935, it was quietly dropped, so hubs from 1935 to 1937 were supplied without NIG. As Michael Caine might say, not a lot of people know that!
        The late great Jim Gill did a lot of analysis of type K hubs and, prompted by your query, I may add this to my website in the near future.
        Cheers,
        Tony

      4. “The late great Jim Gill did a lot of analysis of type K hubs and, prompted by your query, I may add this to my website in the near future.” That would be appreciated very much indeed!

      6. Thanks for your reply Tony. I will clean what I have up, possibly replace the clutch spring as these must fatigue over time, reassemble, and see how I get on.
        Matt

      7. Hi Tony, have now reassembled my hub with new springs and installed in tandem and I have 3 gears, so I am winning. I had to adjust packing washers to get enough frame offset on the RH side and I’m not happy with the amount of axle that extends through the RH dropout (the RH short axle nut is not fully threaded on). Can I swap in a longer axle that will have the same LH dimensions for the hub so that I know the innards will mesh OK? If you can’t help on the specifics of this, can you point me in any direction?

  16. I have an S-2 hub, date-marked 2/68 NOS in its yellow box. But I have not found it in the list above. Can you provide any information on it? Thank you, Remo

    1. Hi Peter,
      It was a very rare hub in the UK, mostly exported to Scandinavia. Pages 143 to 145 of my 1987 book ‘The Sturmey-Archer Story’ provide more information and there is a bit on the Sturmey-Archer Heritage site: http://www.sturmey-archerheritage.com/images/photos/pic-106.1.jpg
      and http://www.sturmey-archerheritage.com/index.php?page=history-detail&id=106
      The hub was made from 1966-72 and gave direct drive and a 28.6% reduction.
      I don’t know of any other technical information but it used the same shell as the AW, FW and AM hubs and is pretty simple.
      I hope this helps!
      Tony

      1. Hello Tony
        Thanks, somehow I must have missed the parts list on the Heritage site. Now wondering how the old S-2 differs from the current S-2 Duomatic hub…

  17. I have heard that Sturmey Archers were once fitted to motorcycles, I have a 1953 New Hudson Auto cycle that has one gear of the drive to rear at a ratio of 1:14 and so could need a lower and a higher gear. I would like to fit a ST but auto cycles have two rear sprockets, one either side .One for the pedal drive and the other for the engine. Can you offer any advice or point me towards information I can use to do this?
    Grateful if you can help

    1. Hi Owen,
      In the Edwardian era, Sturmey-Archer did indeed produce hub gears specifically designed for motorcycles but they were not a success. A hub gear works so well on a pedal cycle because (almost uniquely) a pedal cycle’s primary drive gears up for speed, not down for torque. This is why hub gears can be so small and light compared to gears mounted at the bottom bracket. When hub gears were used with petrol engines, the primary drive was considerably geared down and the hub gears proved unsuitable. They just weren’t tough enough and the problem was exacerbated when the engines became smoother running, which didn’t allow such good lubrication of the meshing pinion teeth in the hubs. Sturmey-Archer then turned instead to countershaft gears and made these successfully for many motorcyle manufacturers, not just Raleigh (who owned Sturmey-Archer). You can find out more about this in Chapter 7 of my 1987 book The Sturmey-Archer Story, which is still available from the publisher and from the Veteran-Cycle Club.
      As regards using a hub gear on a lightweight autocycle, Alex Moulton did some interesting experimental work and I would strongly advise you get hold of issues 2 and 3 of volume 29 of The Buzzing Club magazine (April and June 2010). These contain an illustrated report by David Beare of an examination of Moulton’s prototypes which I arranged in 2010. David is the magazine’s editor and his email address is buzzing@abermule.com
      Tony

    1. Hi Ray,
      Round about 1932, they started adding a single digit to the model initials on the hub. So, for example, a hub marked K2 was a type K made in 1932 and a hub marked KS4 was a type KS made in 1934. It seems a few hubs made (or more finished) during the war also had a single digit year date, which would make one marked 0 after the model initial a 1940 hub. After World War 2, Sturmey started using two digits for the year and one or two for the month, separately from the model initials, so 53 11 was a hub made in November 1953.
      Tony

  19. I have a 1967 schwinn racer, it’s a three speed bicycle with a single gear system on the inside of the rear axle, I belive that’s what it’s called, after replacing the tires and reassembling the bike, the rear tire won’t stay on tight enough and the gear system has all together stopped working. It stays on the most difficult speed and I can’t figure out how to adjust it, I’m used to more modern bikes with several gears that adjust when you crank the lever to switch speeds. I’m unfamiliar with this model and I’m only seventeen lol so this particular bike is far from my day and age. I can’t find many helpful resources to aid me in fixing it. If anyone reads this i would be very thankful to have some help with this. Thank You

    1. Hi Angelo,
      Can you read the name of the maker of the gear and any model numbers? This information is usually engraved or embossed on the shell of the gear hub. That information would help greatly in solving your problem. Maybe a photo, too, if you can get one or two sharp ones. My regular email address is tony.hadland@gmail.com, if you find it easier to send the information by that route.
      Cheers,
      Tony

  20. Hello Tony
    I am looking for a pair Sturmey Archer Tandem Drum Brake Hubs (rear Typ KT-40 Holes and front Typ BFT-40 Holes) from the 19930er Years. If you know anyone or you have any idea who i can find it please send me a mail.

    Many Thanks in Advance
    Frank

  21. Thank you Tony for your kind words, your right the more of these
    items we restore and selvedge from the junk piles the better, i have a real passion for keeping these bikes and components going.

    if any one knows of any old bike’s that are un loved or just left to rot please let me know im in the Leeds west Yorkshire aria will be happy for any info on this thanks

  22. HI my name is giuseppe and i would like to thank you for this very useful resources i have just dissembled and serviced a gh6 dynhub thanks to the info you have provided. 🙂

    now working well after removing all the rust cleaned and re assemble thank you , now just needs new rim and re spooking but the dynohub as good as the day manufactured.

    just dry battery unit to refurbish and wiring and lights which are in a bad way but not beyond hope , they came off a gents Rudge Whitworth single speed bicycle the frame is in a bad way needs but with a little time and elbow Greece it should look like new when done.

    i was a bike mechanic at watts & Cearns lower brigit in Leeds for some years, and loved the work and some one mentioned about servicing a Sturmey Archer 5 speed well that was my speciality aria as the other guys hated touching them, i still do the odd one now and a gain for people i got my qualification at Raleigh centre Nottingham when the original works was still there, and where i bought my brand new Raleigh Record Sprint the original black and gold one with renolds 501 tubing on completion of my training there as a treat to my self . i still have that same bike in original show room condition

    1. Great feedback, Giuseppe – thank you very much. I’m delighted that you found the info useful and that you are keeping these items going. Good stuff!
      Tony

  23. Thanks for the K type instruction. Took a k type apart this morning and have successfully rebuilt it and it now appears to be working fine. Also got a copy of your Raleigh book, like what I have read so far.

    All the best to you for the new year.

    James

    1. Thanks very much for your kind words and all the best for 2014. Glad you found the instructions useful – it’s rewarding to be able to keep these old pieces of kit going 80 or 90 years after they were first used!
      Tony

  24. Thank you for making these documents available,just rebuilt the BSA 3 speed in my old Sunbeam,running like a Swiss watch now,thanks again

  25. Thank you so much for this information. I was having trouble understanding the light set and DBU wiring on my 50s Raleigh 3 speed and now it is well on its way to be fully functional. 🙂

  26. Found an old Dynohub at a recycling centre (on its way to be crunched) and really appreciate the info you provide – i’ve got no excuse to revive it now! I’ll certainly recommend it to other Sturmley Archer fans – Many thanks – Surely this is what the internet was created for!

  28. A friend In Dorset has a Sturmey archer 5 speed, she has trouble selecting gears and i believe the unit needs a service or repair (it is not just the cable adjustor). Can you advise a competent person who could service the hub?

    1. Hi Mike,
      There are a number of people around who could tackle the job. I usually do my own repairs but unfortunately cannot take on extra work. But I have used Peter Read in Milton Keynes (even on a hub that was about 100 years old) and he has been fixing hub gears for many years. His email address is firebird3101@yahoo.co.uk
      If you cannot resolve the problem via Peter, please get back to me.
      Tony

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