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Sturmey S3X: any long term users?

28K views 29 replies 8 participants last post by  sapva 
#1 ·
I have searched for info about the S3X, but most of the reviews/opinions I have found are from its initial release. I was wondering if anyone on this forum has used one for longer than a couple of days, and about your experience with the hub.

Some things that seem consistent:
*It doesn't hold up to aggressive back pedaling (like a skid stop).
*Backlash is about like having half an inch of loose chain.
*It needs fairly regular maintenance to avoid any of the mechanical pitfalls people have had.
 
#2 ·
Not exactly long term, but certainly more than a couple of days - I've been riding an S3X hub regularly for 3 months. I got the hub on the first shipment into the US in early 2010, but it sat for a year and a half before I finished the bike. I had a faulty gear unit originally, which manifested itself almost immediately as loss of engagement in gears 2 and 3. This was swapped out for a warranty replacement, which has been working fine for several hundred miles now. I have mashed on it pretty hard up some hills and it seems solid.

The S3X hub definitely has backlash, much like any other IGH, but a little more than what I am used to on Rohloff Speedhubs. I have the S3X hub connected to a Schlumpf Speed Drive for a 6-speed fixie setup, so the backlash is multiplied, but the SD backlash is minimal on another fixie I have set up with a standard fixed rear hub. The backlash doesn't bother me with my riding style, but fixie riders that want zero play in their drivetrains may not be happy with it.

I use a front brake and use this and back pedaling to slow down - no sliding. The transition between forward and reverse power is noticeable but acceptable for me. Again, this may not apply to everyone.

The gear transitions are a bit clunky/sudden/jerky but I think this is to be expected on a multi-speed fixed gear hub. Shifting the Schlumpf unit with a fixed rear wheel is certainly less smooth than with a freewheel.

The gear box is fairly simple and runs on grease so regular maintenance should be minimal. Outside of adjusting the cable tension following initial stretch, the system shouldn't need any attention outside of changing the grease periodically, probably on the order of 1-3 years like other grease-filled hubs.

Neil
 
#3 ·
Thanks for chiming in. This is just what I was hoping to find out. I am not a fixie purist by any stretch. I enjoy riding it, but I don't enjoy spinning 130 rpm's downhill at 28mph. I haven't really considered running a freewheel on my fixie, but it's nice that the option is there with the S3X if you want to down the road.
 
#4 ·
I'm with you on not wanting to spin a mile a minute, especially on hills that I'm used to coasting down at speed. Going from 1 speed to 2 was a nice improvement and going to 6 makes it feel more or less like a road bike. Not as many choices in between, but a similar overall range.

Good luck in your decision making. The hub is not that expensive if you decide you don't like it later.
 
#5 ·
So, I'm about to pull the trigger on one of these, and I have one last question. Right now I'm going to put it on my cross bike that has 120mm spaced track ends. The obvious thing would be to get the 120 spaced S3X. The question is whether or not the 130 version could be respaced for 120 by removing 10mm's of spacers on the left side. If it would work it might be nice to have some flexibility in the future. If it won't work I'll just get the 120 and call it a day, but I haven't found much tech info about the hub so user information is what I will have to go with.
 
#7 ·
I know that the axle is longer. I guess my question is whether or not this particular hub can be respaced, and run with 10mm's of extra axle sticking out on the left side. I know I would need a new nut of the right thread, but would it work otherwise? The pictures make the axle look a little funky, so It's not clear if this would work.

I know that some of the old SA hubs were adaptable by removing spacers or using a longer axle depending on how you wanted to change the spacing. I was just wondering if this hub is like that too.
 
#8 ·
I ended up with a 120 version of the hub, and built it up in an old Weinmann A129 "Concave" rim.

The hub seemed fine until I mounted it on the bike, and after shifting it a couple of times it would not hit high gear when the indicator chain was slack. It was my understanding that the hub would essentially act like a direct drive hub without the shifter attached, but here mine was freewheeling.

I looked online and found a very good guide for servicing the hub, and followed the last bits about setting the RH cone to a specific location on the axle in order to ensure the travel of the key in the axle. After that adjustment the hub works as expected. It's crazy to think that SA would send out hubs that aren't adjusted from the factory, and fail to include instructions for proper setup. It's lucky that someone has already cracked one open, and detailed the service they did to their hub. It made for an easy adjustment, and a nice ride this afternoon.
 
#10 ·
I built mine into a Surly Moonlander and have been cruising arroyos (sand/gravel washes) since early spring. About 2 months ago, I felt it was well worn-in and tore it down for inspection. No appreciable wear, but I cleaned it out and repacked it with Finishline teflon grease.

Afterwards it seemed to run a bit free-er, certainly no problems. Recently, I have had a couple of instances where after a long run in high gear, the hub is very hard to downshift. Both times, I kept pressure on the shifter (mounted on a Paul Thumby) while trying not to load the chain - and it did shift, and then shifted freely and easily.
 
#11 ·
I have ridden the hub quite a bit since I built it last Spring. I regularly do 20-30 mile road/mixed CX rides on it with no problems. I do have a canti in the front so I'm not laying on the pedals for all of my speed control.

My earlier shifting problem was helped by the RH cone adjustment, but it was brought home with some frame alignment. Apparently, my frame wasn't very well made, and was sent from China, or wherever the eighth inch frames are made, with poorly aligned track ends. The slight bow put into the axle by the misaligned ends was enough to add friction to the keyway, and as a result the shifting into the highest gear was sluggish. With parallel ends the hub has performed flawlessly.

I have the shifter mounted on an old strap on shift lever mount at the seat cluster. So the cable travels straight down the seat stay to the hub. I have had to readjust the endplay a couple of times, but that's pretty easy. Also, the left locknut cracked for an unknown reason, but it was replaced very quickly with a call to SA in California. They thought that I over torqued it, but there is no way I put as much torque on it as it states in all of their literature. I think the metal is just brittle, and hard. It probably was a faulty piece to start with, but that has been the only real problem with the hub, and after at least a thousand miles I think it is looking pretty reliable.

I should pull it apart to clean it, and relube. I'm sure it's time.
 
#12 ·
Well, a sad day yesterday. I was out on my S3X equipped Moonlander - about 7 miles out to be exact - when it slipped in low. I stopped, checked cable adjustment/axle nut tightness/chain adjustment - but all was ok. Tried it again - it held, then once again slipped. Mid gear still worked fine, as did high. I got another mile, and mid started to slip. High still worked - as it should, since it is lockup. Got the bike home, and took the hub apart. The axle key has 2 tabs on it - one kicks the main clutch out (disengaging high/lockup) and the other selects between mid and low. The mid/low tab is almost gone. Just a .8mm thick sliver remains of a bit of steel that was 4x4x2mm. Washing out the planet cluster, I found a fair bit of it - looks like slices, mostly. I've been putting 10-20 miles a week on this hub since early last spring, so it's probably got 500-1000 miles on it. I took it apart in July for rebuild, it looked like this:
Product Lens Technology Photography Cable


The closer tab (above the spring) is the high tab - the other is now gone:
Cylinder

You can see no significant additional wear on the axle. Guess I need to get the "key" out of there and/or see if I can get a new part.
 
#13 ·
I'm surprised to see that specific kind of wear--the mechanism is very dependable, and has been used in SA hubs for some time, in various designs. I wonder if making it a fixed gear design has loaded the axle key in a fashion they didn't intend, since the norm is for the hub to freewheel during shifting.

Anyhow, the indicator chain itself should unscrew counter-clockwise from the axle key. Grab the actual chain bit and spin, it should come undone without much fuss.

A quick search didn't show a blow up of the S3X, but the axle looks identical to their other 3 speed models. Reference Sutherland's book. Assuming the same service instructions as the rest of their hubs, grease the bearings and oil the rest.

Hopefully the axle key is the same as the rest of them, as well.
 
#14 ·
I've got the indicator chain/pin unscrewed - and you're right, that would let the key drop out in a normal hub. But this bad boy is single sided. Look at the "worn" shot. Only sticks out on one side. The key seems to be held in the slot by springs on both sides. There must be some retainer in there to keep the spring ends in place, or maybe everything goes in via the slot. Gotta flush out the grease and get a good look.
 
#16 ·
Thank you for the info! From your link service:
"7. Remove the circlip and withdraw the axle from the planetary gear
unit, which is riveted together and cannot be further disassembled.
Likewise, the compensating spring and axle key cannot be easily removed
from the axle."

and from your link S3X Analysis
"On the other hand, the sliding axle key, which is required to move the main clutch and to lock the suns, is very small. The dog which does the sun-locking part was very shiny on one side after only 200 miles' use. I don't know what proportion of the total torque has to be resisted by the sun/axle attachment (the AW gets away with a small cotter pin) but, coupled with the loose fit and frequent reversals of drive, it doesn't quite seem up to the task. The slot in which the
axle key slides also shows significant wear marks on its edges.

The key is not easily removable from the axle as it is held tightly between two halves of a long compression spring (what was called a "compensating
spring" on the old FW), and it would be best if SA made the axle, spring and key assembly available as a spare part considering that all of these
will wear. Nothing else in the hub showed any signs of wear beyond the normal light polishing from running-in."

I'm going to use the 5W service guide instructions approach to see if the key will come out, but I'll try SA for parts.
 
#17 ·
I was able to disassemble the Gear Selector Key from the axle assembly, and it does look like this:
Line Metal Composite material Steel Iron

with the exception that the tabs are fully square with no beveled edges. The med/low tab is spring loaded.

To remove the key, use a tool to push the compression spring (where the indicator would be) to the end of the slot. Then move the key in the same direction while lifting up/out. Voila!

Also, Sunrace/Sturmey Archer USA rep returned my call and will be sending out both a new axle assembly and shifter. Apparently the indexing in some shifters was questionable, not giving full engagement of the med/lo tab even when properly adjusted.

Pics when it arrives.

Many thanks to John_Dalhart for his info.
 
#18 ·
SunraceUSA responded quickly and got me a whole new internal set and shifter - ready to drop into the hub shell and go.

But I just had to see a few things.

Here's the new selector key:
Black Grey


You can see the change in the "high" section - it's lost weight from that cutout and is actually shorter in the body, while it's tab is still where it always was. I can't tell any difference in the "low/mid" section.

I also looked carefully at the engagement teeth in the gearset (where that "low/mid" tab works) and saw no difference in tooth shape.

Now to reassemble it and get some miles in.
 
#19 ·
Thanks for all of the info on your rebuild. I haven't taken mine apart yet, and I suspect I should. I have about the same mileage as you had prior to losing your low key. It is good to know that the parts are available for the rebuild. The hub was designed for grease, but the SA grease doesn't seem to be available. What did you use for lube?
 
#21 ·
I would like to get one of those hubs but only if there isn't a design fault that leads to premature wear. If it only has 500-1000 miles of life expectancy before it needs rebuilding then I'm not interested. Do you think that the problem that caused the abnormal wear is now rectified?
The stock lube is a very oily light grease, reminds me of the stock Shimano hub grease - a light transparent green. The assembly came in a plastic bag, which had caught the draining oily part of the grease. The original hub was exuding oil from every orifice until it's first rebuild.

I used Finishline teflon grease, which I have had very good luck with in the past. I was a bit concerned because it is thicker grease, but then the hub ran easier once reassembled. The one drawback to this grease is that it reacts with aluminum. The grease I had placed where the steel internals drive the aluminum shell had turned completely black - something I saw once with an aheadset wedge, but had forgotten. No sign of corrosion on the aluminum shell, but I won't do that again.

When I tore down the hub after the key went away, there was still plenty of grease in that area - no "clean wiped" spots at all. After solvent immersion, no significant damage to the engagement teeth inside the gear cluster:
Steel Circle Aluminium Household hardware Silver


I figure the face of that tooth in the middle of the pic, along with it's buddies, is what was peeling slices off the key - but it is all still square-edged, and not even shiny on the face where it would have been rubbing.

Have they fixed the problem? They have obviously done some rework of the key (at least the "high" tab), the engagement teeth look fine and the new ones look identical. The shape of the "low/mid" tab is identical, but perhaps the metal is different? The discussion with SunraceUSA rep said they had some early shifters were not holding the key in the right place and causing issues - so I've got a new shifter as well.

Realistically, this is a very easy hub to service. You do need the SA body wrench if you don't want to knock the ring loose with hammer/punch, but unscrew the nondriveside axle nuts and the body and the assembly comes out. Undo the driveside axle nuts and remove one snapring and the rest comes apart. Reassembly requires no "hold your mouth right" to speak of.

For the next build, I'm thinking about trying a different grease - either Dumonde Tech MR (micro resistance) grease or EP moly grease. None of these have shown any oil separation even in the summer heat here (100-115F).
 
#23 ·
John- Thanks for the info about the grease. I guess I was used to the other igh's with the "secret" grease formula, so I didn't even try to find it. I saw the SA grease listed on the Persons site, but they didn't have any prices, and it almost looked like it was informational only. Other stuff on their site is listed with prices, and you can purchase via the internet. I will head over to the local mower repair store to get some 00 grease, and an old pair of channelock pliers to grind into a ball ring tool. The mower shop is also a used tool store.

I'm going to pull my hub apart next week and see what it looks like in there. After thinking about it more I suspect that I have well over a thousand miles on this hub. I remember putting 150 on it in the first two weeks. I don't usually use my gps with that bike, but I might start.
 
#24 ·
I opened up the hub this afternoon, and it looked really good. The surface of the "low key" that engages the sun gear had some polish, but there weren't any signs of it being cut, or abraded. The planets and the main axle had a little polish on them as well, but nothing to be concerned about. The grease was for the most part in good shape, but it was a bit "gray" which I would attribute to the break in period, and the subtle polish on the various surfaces.

It was a super easy tear down/repack. I used 00 grease from the mower store. The bulk of the time was in cleaning the parts. It went back together in a few minutes without a hitch.

The ball ring pliers that I made out of an old pair of 12" chanelocks was perfect. I picked up the pliers for $5, and it took about 5 minutes with the angle grinder to turn them into a decent set of lockring/ball ring pliers.

After looking at wadester's posts and comparing to my hub I feel pretty good that the shifter was the culprit. Either that or I happen to have a low key that is made out of a harder material, but I don't think that's it. My low key shows no sign of partial engagement. It is good peace of mind to know that the hub is in good shape in light of the photo's in the thread.

I wouldn't shy away from one of these hubs. It seems like SA has the problem under control.
 
#27 ·
This is ancient, but... I bought one (most likely 2010 model) in 2011. After roughly 8-10k miles it still functions perfectly with zero service.

Notes: I don't do aggressive back pedaling, but frequently resist hard to stop, and when going downhill. And something not mentioned specifically in the thread, 1st gear is completely useless, like pedaling through molasses, and early on when trying to use 1st gear on hills I would have to shift up to 2nd for relief.
 
#28 ·
After that many miles the hub should be settled in. You shouldn't feel so much resistance in the low gear. I suspect that if you pull it apart you may see signs of poor key engagement. Do you have it set up with a little end play on the axle? If you don't have the end play it could cause binding, out even failed shifts.

I can feel the hub in low gear, but it's not bad.
 
#30 ·
That is what I thought, it would break in, but it never did. The upper gears are fine but 1st still has resistance. Might be my gearing that makes it more all the more noticeable. Initially I had it set up with 53x13 (110 gear in.), but that turned out to be way too steep for anything but sprint training. After a few months I backed it off to 51x16 (92 gear in.) which was the sweet spot where I could ride most anything on the road using 2nd/3rd. It has the recommended axle play, and shifting has been perfect. The cable adjustment is very finicky, but you get used to that.
 
#29 ·
I don't feel any real difference between 1&2 as far as friction type resistance - and only a little change going to 3 (direct drive).

I do note that I've cleaned my internals and regrease several times. I'm using Sta-Lube blue Marine Grease (waterproof!) w/o issue.

I have, however, had to replace my shift key twice now. Both times it was working fine - right up 'til it wasn't. The gear cluster teeth just nibble away at it slowly until there's not enough left. I never shift under load, always try to let things go where they need to be before doing more than just moving the cranks/letting them move. I do, however use my hub for actual technical trail riding, so I am putting high loads on both pedalling and resisting.

I note that the failed keys didn't have signs of being twisted/overloaded - and had reasonable square ends - but had drastically reduced width. Nibbled to death.
 
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