Bicycle Mechanics - Cutting (shortening) Sturmey Archer axle

I've installed a SA hub on a bike and the axle protrudes too far on the non-drive side. I've heard people talk about shortening them with an angle grinder, a tool which I've never used before and currently don't own. Is it fairly straight-forward to cut the axle without distorting the threads too much? Is an angle grinder the way to go with this and is there any particular technique to follow to obtain the cleanest possible cut?

how far does it protrude? you do have the antirotation washers in it don't you? unless you and your friends and banging your shin on it when you walk by I am not sure I would cut it.

Which hub is it? If it is any of the solid axle types like the 8 speed or rotary shift 3 speed, cutting the axle should not be a problem. If it is any other type that shifts with an indicator chain (hollow axle) it should not be cut on either end.

It's an older X-RF5 so yep, the axle is hollow. I thought that there's no problem altering the length on the non-drive side. . . the bike is a brompton so it would be preferable to have things fit cleanly. Unfortunately I couldn't get hold of a narrower axle length hub for a decent price so I decided to use an X-RF5 that I had spare.

I've serviced these hubs myself quite a few times but I've never got down past the planet cage as I don't have circlip pliers, so I've not examined how the 'gear selector key assembly' works with the ball bearing thingies. . . I assumed the non-drive side of the axle was solid all the way to the sun pinions?

Refer to page 4 of this document. http://www.sturmey-archerheritage.com/files/view-287.pdf
Iv'e had this model hub torn down to this point, and I heeded the admonition to not remove the shuttle pin, so I have no idea how far it extends past the locking balls.
I'd hate to find out how long it is by cutting into it.

Hmmm, I can't really get much sense of those parts from that diagram. Ah, page 8 gives some indication. . . I wonder how accurate it is?

Is there a reason why the shuttle pin isn't shown in the exploded diagrams; it's mentioned in a kind of passing way? I'm guessing I can disassemble those parts and measure how far the hollow section of the axle extends?

Is there a reason why the shuttle pin isn't shown in the exploded diagrams; it's mentioned in a kind of passing way? I'm guessing I can disassemble those parts and measure how far the hollow section of the axle extends?
I presume they don't show it in the detail because it is not supposed to be messed with. It might be that without specialized assembly equipment, it's not possible to re-install it.
If I ever get my hands on one that has past it's useful life, I'll try to find out.

the hollow section extends to the center where the shifting piece is coming out the sides.

You will welcome the extra left side length when you try to mount a trailer ..
many attach under the axle nut to mount, ..
the axle is hardened steel , you bugger up the threads with anything you do to grind off length..
then you cannot get the nut back on..
put nut on then grind/cut is a standard procedure..

You could Overhaul the hub and substitute a shorter axle..
new indicator chain may need be bought too, if right side length also changes.

My recommendation, leave as is put a plastic acorn nut on the end
if you worry about kneeing the edge. .

how much is concerning you.. inches or MM?

It's about 20mm longer than would be optimal and perhaps 10mm longer than would be 'acceptable'. . .
I think I've realized that I've got a kludge option. . . I can get hold of a shorter axle but I'm limited to this shell for which the shorter axle wasn't designed. So the resulting hybrid might be a bit short on the non-drive side but hopefully only by 3 millimeters or so. Which is almost perfect. I hope I've done the maths right. . . guess it'll only take an hour or so to do the work and find out.

Currently DIY mechanics is consuming my life. I like it, to a point, but I could do with being finished with this mini-project.

Oops, no, don't think that's going to work, cutting the axle might be the only option.

put nut on then grind/cut is a standard procedure..


On 3 speed SA hubs or all types? The shuttle pin part has thrown me.

On 3 speed SA hubs or all types? The shuttle pin part has thrown me.
The pin extends farther through the axle on a 5 speed than it does on a 3 speed. The pin is ramped to either push the locking balls out to lock a sun gear to the axle, or drop into the recesses to allow the sun gears to rotate freely. Which sun gear is locked to the axle determines your drive ratio in all but 3rd gear.
This function does not exist in a 3 speed. It's the primary difference between the two.

Yeah, I've got a rough idea of the way it works. . . I've ordered some very cheap circlip pliers, I think I'll take a proper look at the mechanism and try to determine how much spare axle there is. From that diagram of the X-RD5 hub it looks as though there's 20mm max and a comfortable 10mm that can be removed, if it's accurate.

Yeah, I've got a rough idea of the way it works. . . I've ordered some very cheap circlip pliers, I think I'll take a proper look at the mechanism and try to determine how much spare axle there is. From that diagram of the X-RD5 hub it looks as though there's 20mm max and a comfortable 10mm that can be removed, if it's accurate.
Well, if you go ahead with cutting it, i'll be interested to know the outcome.

I got some circlip pliers today so I dismantled the hub futher than I'd been able previously, but having gotten down to the axle it appears that the axle internals can't be removed and so there's no way of finding out how far the hollow section extends. At least as far as I can see. . . weird, as there are springs in the axle and you'd think that as springs have a finite lifespan they ought to be serviceable.

I think it's safe to say there's nothing going on inside the spindle at that point; the Shimano 3S hub I had apart the other day was solid all the way to the sun gears.

I think you're silly to fret about it; just cut your 20mm off. As mentioned, do it with the nut already on. I find a slight chamfer helpful when cutting threaded stuff.

The SA 5 speeds are different, Kimmo.
I contacted SA about this but they didn't offer any further incite. So the only thing I have to go by is the X-RD5 technical manual.

The put the nut on first is a common sense, thinking ahead procedure,
any time you cut a bolt.

There are short axles made for like Bromptons, when they fit a AW3 hub ..
120mm dropout .
the old 2 cable 2 shifter 5 speeds went out of production long ago,
but there was that option on Mk2 Bromptons, back in the day.

SJScycles in England a good source to try, it seems, for Sturmey spares
from older eras.

Well, I went ahead and removed about 12mm which I thought would leave me enough axle if I ever switch this hub to another frame, and it proved to be solid in that area. So the gamble paid off.

I used a very cheap dremel imitation and the cutting disks that came with it, which weren't really up to the task 3 breaking in the process (good to have safety goggles on when the bits of blade fly across the room). It took a long time but the result is fine; there's zero chance of spoiling the threads with this method of cutting.