Moulton AM5 Sturmey Archer hub

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AndyPat
Posts: 6
Joined: 16 Sep 2018, 3:42pm

Moulton AM5 Sturmey Archer hub

Postby AndyPat » 16 Sep 2018, 3:53pm

My Moulton AM5 Sturmey Archer 5 speed Sprinter hub needs repair or replacing. Can you suggest who/how/where best to have this done?

What is the availability of old Sturmey Archer parts, like the Sprinter control lever, sprockets etc.?

Is it possible to fit a 7 or 8 or 11 speed hub to a 1996 AM5? I currently have 15T x 50T giving a range of about 38" to 85".

The Sturmey X-RF8 looks ok for small wheels but what sprocket/chain wheel would fit the frame? Has anyone used an X-RF8 on an AM frame?

Brucey
Posts: 31105
Joined: 4 Jan 2012, 6:25pm

Re: Moulton AM5 Sturmey Archer hub

Postby Brucey » 16 Sep 2018, 8:08pm

you can buy spare parts (including a new internal) from SJS. You can also get a new shifter there that is the right one for a 'sprinter' too.

The SA 8s hub suits small-wheelers fairly well, in that it only gears up (i.e. bottom gear is 1:1 ratio, so a 30T chainring and a 20T sprocket would give a gear about 30" on a moulton with 20" wheels). However it is heavy, inefficient, and prone to wearing out/breaking. Gear ratios aside perhaps, a shimano Alfine 8 hub (or a 'premium' quality nexus 8) is a much better hub.

FWIW the most common faults with 'sprinter' 5s hubs are resolved by fitting a new axle assembly (including sun pinions), the snag being that there are two types (dog-locker and ball-locker) and you won't know (for sure) which it is until you take it apart. The other parts which often break in sprinter hubs are inexpensive and/or common with NIG type 3s hubs.

BTW one of the conversions you can do is to fit a BWR driver and convert a 'sprinter' hub to accept two sprockets, thus extending the gear range once a derailleur is fitted.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Slowroad
Posts: 615
Joined: 28 Jun 2008, 9:58pm
Location: Nottingham, UK

Re: Moulton AM5 Sturmey Archer hub

Postby Slowroad » 3 Oct 2018, 9:41pm

I've got a 1999 Brompton with a 5-speed hub which jumps in 1st and 4th. After being overhauled several times this doesn't get any better, and it seems that it is just worn out. Would I have the same options as the Moulton owner?
Thanks!
“My two favourite things in life are libraries and bicycles. They both move people forward without wasting anything. The perfect day: riding a bike to the library.”
― Peter Golkin

Brucey
Posts: 31105
Joined: 4 Jan 2012, 6:25pm

Re: Moulton AM5 Sturmey Archer hub

Postby Brucey » 3 Oct 2018, 10:02pm

Slowroad wrote:I've got a 1999 Brompton with a 5-speed hub which jumps in 1st and 4th. After being overhauled several times this doesn't get any better, and it seems that it is just worn out. Would I have the same options as the Moulton owner?
Thanks!


yes pretty much but note that Bromptons use a narrow OLN measurement which restricts your choice of gear in a standard frameset.

One thing that you should be absolutely clear on is that

a) Only a 'sprinter' shifter will work a 'sprinter' hub; other SA 5s shifters (eg for (W) hubs) are not gonna work
b) SA make a nice looking thumbshifter (with a red bezel) that has the correct cable pulls for a 5s sprinter hub
c) said shifter is, like all SA thumbshifters of similar ilk, a pile of poop.

Re c) the shifter overshifts and sticks between downshifts in some gears, which causes slippage and therefore damage. [This can only be cured properly by rebuilding/modifying the shifter, which is a complete PITA and requires special tools.] However one gear that doesn't suffer thusly is gear 1 so you might have a duff shifter but this probably isn't your only problem.

When your hub has been 'overhauled', what has been replaced? Do you know if you have a dog-locker or a ball-locker?

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

AndyPat
Posts: 6
Joined: 16 Sep 2018, 3:42pm

Re: Moulton AM5 Sturmey Archer hub

Postby AndyPat » 4 Oct 2018, 7:22pm

It seems that SJS cannot supply any parts for the Sprinter hub. The cycle shop in Stratford on Avon is suggesting the X-RF8. For a 17" wheel with 28 spokes it looks like viable option.
I've had very good experience of the old Sprinter so will be sorry to see it go but it seems the possibilities of keeping them going are extremely limited.

Brucey wrote:you can buy spare parts (including a new internal) from SJS. You can also get a new shifter there that is the right one for a 'sprinter' too.

The SA 8s hub suits small-wheelers fairly well, in that it only gears up (i.e. bottom gear is 1:1 ratio, so a 30T chainring and a 20T sprocket would give a gear about 30" on a moulton with 20" wheels). However it is heavy, inefficient, and prone to wearing out/breaking. Gear ratios aside perhaps, a shimano Alfine 8 hub (or a 'premium' quality nexus 8) is a much better hub.

cheers

AndyPat
Posts: 6
Joined: 16 Sep 2018, 3:42pm

Re: Moulton AM5 Sturmey Archer hub

Postby AndyPat » 4 Oct 2018, 7:27pm

Take a look at http://www.kinetics-online.co.uk/foldin ... speed-kit/ that may be an option for your Brompton.
This chap in London may be able to repair your SA hub, try bicycle.ninon (at) gmail.com or phone 07410 699 297

Slowroad wrote:I've got a 1999 Brompton with a 5-speed hub which jumps in 1st and 4th. After being overhauled several times this doesn't get any better, and it seems that it is just worn out. Would I have the same options as the Moulton owner?

Brucey
Posts: 31105
Joined: 4 Jan 2012, 6:25pm

Re: Moulton AM5 Sturmey Archer hub

Postby Brucey » 4 Oct 2018, 8:41pm

AndyPat wrote:It seems that SJS cannot supply any parts for the Sprinter hub....


clearly they don't know what they have then, or you didn't ask the right questions. I see quite a few, including internal HSX140 and axle HSA649; these parts differ from the sprinter as fitted to a Brompton originally only in axle length. There is also a bare axle to fit a ball-locker, as well as ball-locker sunpinions and a whole load of other stuff.

You can verify part numbers yourself by checking out the pdfs for spares that are available online.

Also check out 'the cycle division' they have a very good selection of spare parts.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Slowroad
Posts: 615
Joined: 28 Jun 2008, 9:58pm
Location: Nottingham, UK

Re: Moulton AM5 Sturmey Archer hub

Postby Slowroad » 5 Oct 2018, 7:56am

Brucey wrote: . . . yes pretty much but note that Bromptons use a narrow OLN measurement which restricts your choice of gear in a standard frameset.

Thanks - the fact that this goes largely 'over my head' makes me think I'm substantially out of my depth and it's not something I should take on myself! What's a OLN measurement? I'll have to ask my Brompton guru re your other questions... Thanks for the dose of reality re the thumbshifters, that is obviously not mentioned on the websites that want to sell one the conversion kits!
“My two favourite things in life are libraries and bicycles. They both move people forward without wasting anything. The perfect day: riding a bike to the library.”
― Peter Golkin

Brucey
Posts: 31105
Joined: 4 Jan 2012, 6:25pm

Re: Moulton AM5 Sturmey Archer hub

Postby Brucey » 5 Oct 2018, 8:36am

OLN = Over Lock Nut measurement. IIRC Bromptons use ~116mm. Not every hub can be respaced to this dimension, which means that many of the hubs that you might think of fitting require that the swingwarm is replaced or modified.

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Slowroad
Posts: 615
Joined: 28 Jun 2008, 9:58pm
Location: Nottingham, UK

Re: Moulton AM5 Sturmey Archer hub

Postby Slowroad » 6 Oct 2018, 12:19pm

[quote] Slowroad wrote:
I've got a 1999 Brompton with a 5-speed hub which jumps in 1st and 4th. After being overhauled several times this doesn't get any better, and it seems that it is just worn out. Would I have the same options as the Moulton owner?
Thanks!



yes pretty much but note that Bromptons use a narrow OLN measurement which restricts your choice of gear in a standard frameset.

One thing that you should be absolutely clear on is that

a) Only a 'sprinter' shifter will work a 'sprinter' hub; other SA 5s shifters (eg for (W) hubs) are not gonna work
b) SA make a nice looking thumbshifter (with a red bezel) that has the correct cable pulls for a 5s sprinter hub
c) said shifter is, like all SA thumbshifters of similar ilk, a pile of poop.

Re c) the shifter overshifts and sticks between downshifts in some gears, which causes slippage and therefore damage. [This can only be cured properly by rebuilding/modifying the shifter, which is a complete PITA and requires special tools.] However one gear that doesn't suffer thusly is gear 1 so you might have a duff shifter but this probably isn't your only problem.

When your hub has been 'overhauled', what has been replaced? Do you know if you have a dog-locker or a ball-locker?

cheers[quote]
Thanks - my Sturmey Archer learning curve is steepening! I've been reading another older thread on 5 speeds viewtopic.php?f=5&t=85275&start=60 which has been really useful. Re my hub, it works really smoothly on the workstand, but under load uphill it occasionally jumps rather drastically in first, putting me off using that gear. It also jumps much less noticeably and regularly every 10 or so pedal rotations in 4th, which is annoying but can be avoided by free-wheeling every 8 or so pedal rotations... Are those symptoms diagnostic of any particular wear or malfunction? I'm not sure if anything has actually been replaced, and not 100% sure re ball-locker or dog-locker, but the LH side of the axle is flat, not chamfered, which I think you've said else where indicates that it is likely to be a dog-locker. The hub has '99-3' printed on it, does that mean anything?
Thanks! (And sorry if I've rather taken over a slightly different topic...)
“My two favourite things in life are libraries and bicycles. They both move people forward without wasting anything. The perfect day: riding a bike to the library.”
― Peter Golkin

Brucey
Posts: 31105
Joined: 4 Jan 2012, 6:25pm

Re: Moulton AM5 Sturmey Archer hub

Postby Brucey » 6 Oct 2018, 1:36pm

OK it does indeed sound as if you probably have a dog locker. '99-3' refers to the date of manufacture of the hubshell. It doesn't guarantee the internals are a particular type (they made both sorts at about the same time) and anyway the internals may have been replaced with either sort during a 'repair'. From the symptoms you describe the first things I would check are that that shifter is the right type (photo?) and that the cable is good (not draggy) and the adjustment is correct.

If you do find that there is something amiss outside the hub (an external fault), if it has been that way for long enough the inside of the hub may be damaged.

The slippage in fourth gear may be a worn/badly engaged high gear clutch; the pockets in it may be worn. This can be corrected by replacing the clutch or by refurbing it; with care it is possible to regrind the pockets (using a dremel tool with square-ended stones) and/or refurb /replace the parts that the clutch bears against. However the root cause of the wear may be an external fault or that the springs inside the hub are not doing their job; there are several springs that fight one another to establish the position of the high gear clutch (and the sun pinions).

The slippage in fourth gear might also be poor engagement of the ring gear pawls with the hubshell, but if so the same fault would be very likely to occur with fifth gear too.

The faults in both first and fourth gear might well be a problem with the axle dogs themselves; again caused originally by an external fault of some kind.

http://www.sturmey-archerheritage.com/images/photos/pic-169.1.jpg

Image
dog locking type axle (photo borrowed from Rogerzilla); is either a sprinter or a (W) hub; they are different but look similar

The axle above is set in the gear five position, i.e. with both dogs set leftwards. You can see where the sun pinions usually rotate by the wear marks on the axle. If the dogs are left (L) and right (R) and the sun pinions are big (B) and small (S) then the sun pinions are locked to the axle/loaded by the following combinations;

Gear five; RB (load CW)
Gear four; LS (load CW)
Gear Three; LS (but there is no load passing through it, the hub is direct drive)
Gear two ; LS (load ACW)
Gear one ; LB (load ACW)

you can see that the L dog does most of the work, but if it (or the mating parts in the sun pinion) is/are worn on one side only, this can generate faults in some gears but not others.

To artificially increase the stroke of the shift arrangement/reduce shifting baulks both the dogs and the sun pinions are sprung. IIRC both sun pinions move on the axle sideways, into different positions depending on the gear selected. Dog L is able to move temporarily so that downshift cable movement is not obstructed. It is a clever way of using a long cable pull to work a mechanism that ought not move that far, but it has consequences. One consequence is that the optimum shift technique is to pedal forwards whilst shifting, but without load; this allows the gears to engage consistently; backpedalling or static shifting won't always select the new gear and can result in a crunch as it goes in; if you start pedalling hard before the gear has gone in, you can damage the hub.


As a general point I think it is a very bad idea to have a hub repaired without being 100% sure of the shifter and the condition of the cable. I would have the cable replaced as a matter of course and I would check the shifter over very carefully indeed or just replace it.

it may be possible to rebuild a dog-locker with a ball-locking axle assy but I have not tried this. I have fixed lots of both sorts of hub and there are quite a few parts that can give trouble. It is also possible to generate problems with fairly small changes to the way the hub is assembled.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Slowroad
Posts: 615
Joined: 28 Jun 2008, 9:58pm
Location: Nottingham, UK

Re: Moulton AM5 Sturmey Archer hub

Postby Slowroad » 7 Oct 2018, 8:30pm

As a general point I think it is a very bad idea to have a hub repaired without being 100% sure of the shifter and the condition of the cable. I would have the cable replaced as a matter of course and I would check the shifter over very carefully indeed or just replace it.

Thanks - it's had these issues for the 8 years or so that I've had it (it was a second-hand buy from a local bike refurbishment scheme) and the gear cable has been replaced in that time so that's maybe less likely to be it. Still worth looking at though. It does have the right sort of gear shifter, the one with the red plastic screw head on it.
The sheer complexity of hub gears is tending to send me to the simplest solution (other than buying a new bike!) which is, I think, to get a new 3-speed hub. I'll need a new shifter though as well.
Cheers!
“My two favourite things in life are libraries and bicycles. They both move people forward without wasting anything. The perfect day: riding a bike to the library.”
― Peter Golkin

Brucey
Posts: 31105
Joined: 4 Jan 2012, 6:25pm

Re: Moulton AM5 Sturmey Archer hub

Postby Brucey » 8 Oct 2018, 2:31pm

if a gear has been slipping (even occasionally) for eight years then the chances of wear or damage arising inside the hub are substantial.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Slowroad
Posts: 615
Joined: 28 Jun 2008, 9:58pm
Location: Nottingham, UK

Re: Moulton AM5 Sturmey Archer hub

Postby Slowroad » 8 Oct 2018, 8:02pm

if a gear has been slipping (even occasionally) for eight years then the chances of wear or damage arising inside the hub are substantial.

cheers

Indeed! The bike does seem to have had a busy commuting life with a tall rider (long seatpost) for the first 12 years of its life (worn paintwork, etc.) It hasn't been used nearly as much over the 8 years I've had it, it has periods of semi-hibernation and an annual cycle holiday (with a short rider!)

Readers of this thread might find useful this response from SJS Cycles re which hub they recommended:

Either the 5spd or the 3spd can be fitted, the 3spd hubs will have a wider ratio than your old 5spd hub but just with larger steps between the gears.
The newer 5spd hubs will required new shifter as well so you’re not saving any money by sticking with the 5spd.
In terms of reliability the 3spd is definitely the one to go for as they will outlast anything.
I hope this helps


I'm in no hurry to get this done, but it looks like I'll be getting a 3 speed.
Cheers
“My two favourite things in life are libraries and bicycles. They both move people forward without wasting anything. The perfect day: riding a bike to the library.”
― Peter Golkin

Brucey
Posts: 31105
Joined: 4 Jan 2012, 6:25pm

Re: Moulton AM5 Sturmey Archer hub

Postby Brucey » 8 Oct 2018, 9:34pm

in a Brompton I think the 6s option they offer is a good choice too, if 3s is not enough for you. If you like very much more closely spaced ratios, then (using a BWR driver) it is possible to convert a standard NIG AW to a 6s setup also, but the intervals between the gears are somewhat closer.

you can see a BWR based 6s setup (33" to 100") vs an AW based 6s setup (42" to 86") here

http://ritzelrechner.de/?GR=BBWR&KB=50&RZ=16,13&UF=1330&TF=90&SL=2.6&UN=MPH&DV=gearInches&GR2=SAAW&KB2=50&RZ2=15,13&UF2=1330

the former uses sprockets of 13 and 16. The latter uses sprockets of 13 and 15.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~