I have a suspicion you can determine that by looking for one that matches the Allen key sizing.
Could you perhaps take the grub screw out of the other shifting button and find a match via that - shops etc?
I’d probably go for a box set of grub screws (cup end) and see if they look the same.
240 Pcs Grub Screws Set, 304 Stainless Steel Hex Socket Cup Point Grub Screw Hex Head Allen Screw Set M3/M4/M5/M6/M8 Screws Assortment Kits with Allen Key Wrench Amazon.co.uk
M4 according to this: http://www.schlumpf.ch/hp/handbuecher/Montageanleitung.KH.engl.10.1.pdf
(But I’d personally just take the other one to a hardware store, they should have a good selection to match it up…)
If you need to find the thread size, just find a bolt that threads in. It’s usually easier to find a handful of bolts or machine screws than a selection of grub screws. Then all you need is the length which can be found from the other one. Or you could use a magnifying glass and a caliper to measure thread pitch and diameter and compare your readings to a chart of sizes. Those are the methods I typically use when trying to find thread size of obscure items. Once you figure that out, McMaster Carr will 100% have the one you need if you can’t get it at a hardware store.
+1 McMaster Carr
Does someone know how many of the thin shims are needed for <M399 models between the bearing and snapring?
Under the snap ring on the left side, I have one 0.10mm shim.
On the right side, I thought there were 2 when I disassembled it in the past.
However, I just found that I have 4… 3 are 0.1mm, and one is 0.2mm. I’m not sure if there were always 4 and they had just stuck together, or if I messed up somewhere.
With 0.1mm shim on the right side, I can noticeably move the axle left and right.
With 0.2mm, I can still move the axle a tiny bit
With 0.3mm, it feels like there is zero movement
With 0.4mm, it feels like there is zero movement. maybe a bit less than 0.3mm
With 0.5mm, same as 0.4mm.
Behind the frame bearings, there are 2 thicker 0.5mm shims for both left and right. Those I think I have correct.
Edit:
I think the snap rings and shims just “preload” the frame bearing + large hub bearing, keeping the hub shell/axle/sun gear from sliding left and right?
Cross section image showing left side sideload path through snapring, 0.1mm shim, 42mm bearing, sun gear, 62mm bearing, hub shell.
I’m pretty sure, that te actual amount of shimming is determined by the tolerances of the other components and thus is individual for each hub.
I just noticed that I have significant lateral rotational play.( I’m not sure what the correct term would be for this). Not the crank rotational play I normally hear about.
When I hold the frame, I can wobble the wheel side to side. I can feel movement between the hub sheel and the frame.
Less shims makes it a tiny bit worse, but even with all the shims, there is still this play. I also don’t think I can add anymore, as it is difficult to get the snap ring to fit into the groove as it is.
I’m assuming it is movement of the large hub bearings?
I noticed the large bearing around the sun gear fits very loosely into the hub sheel Is hits normal?
Video of the movement
Diagram of where I am referring to.
I remember @jaco_flans asked for the same issue a few months ago. But I don’t recall the answer.
Do you have a BrakeFast? It may increase the issue.
Yes, I do have Brakefast. I realize that this would increase chance of occasional brake rub. But I don’t think I have ridden enough for Brakefast to be the cause.
I initially had too much brake rubbing with Brakefast. But I “fixed” that by adding shims under a few of the 6 rotor bolts helped make it “flatter”.
I’d suggest you to check every tiny screw on the BrakeFast. I had similar issue before a bunch of screws have broken. This may be something different, but we’re never too sure!
I find seeing this kind of thing in a video pretty hard unless the frame and camera and held stationary and the wheel is then flexed left and right.
There was a post that might be akin to what you’re seeing here on the Geared Unicycle Group on FaceBook
https://m.facebook.com/groups/268679360444983/permalink/908154359830810/
Again with this video I think I see the slight bearing lateral shift.
What version / serial hub do you have?
Yesterday I was worried my older gen - non-ISIS G36 had some flex in the lager hub body bearings. But it was more an optical illusion of the way the wheel and frame can slight flex and appear to when being held.
Are you noticing the flex you see while riding?
M0399
Here’s a second closeup video showing the bearing movement inside the hub shell.
It’s small so I do not notice while riding.
edit: The How It’s Made youtube video shows that this bearing is pressed into the hub shell… But that looks to be a >M0399 version.
What are the risks of a few slightly loose spokes on a Schlumpf?
I mean loose when I squeeze them spoke to spoke. Some squeeze more easily. Others feel pretty much like my other rides, perhaps a smidge more flexy.
I feel zero issues when riding.
Been riding my G26er more aggressively these last few days and I suspect it is in shock and the wheels spokes have loosened a bit here and there.
It’s still running true, and their tension on most spokes… but I am wondering if is should:
I kind of worry my OCD re schlumpfs could have me try and fix something that isn’t broken.
And from what I understand over tensioned spokes would be more of a risk to damaging the hub. (Do not want)
Undertensioned spokes - what are the risks for leaving these? 
Under tensioned spokes will take less of the loads and the stress of the wheel. Instead the other spokes will take more stress.
This may result most commonly in other spokes snapping or worse a number of spokes snapping in chain reaction on a bigger impact, or, probably least favourably, spokes tearing out one or more spoke holes in the hub … or no consequences at all, as the wheel might still be plenty strong to handle the loads it receives. That of course depends on the wheel, how it’s built, the rider weight and its riding style.
Bringing a few loose spokes back to tension is rather easy and effective. 1.) Let most air out of your tyre, 2.) give one after another a quarter turn, 3.) check whether they feel about equally tensioned and if not continue with step 2. Voilà.
If i rememember it right, Florian used to glue in bearings when they had play. I think he used Loctite 638 or 641 for this. To shim it for a nice press fit, the gap will be too small at the moment.
Perhaps counterintuitively under-tensioned spokes are at risk of breaking due to fatigue – see my comment in the post linked below and the accompanying video.
Do you mean to first try loctite? And that shim is too thick?
The radial movement I see is very small. It’s hard to tell how much it is. You could try fitting foil or something like it but it will be pretty hard to install if even possible. The Loctite bearing glue is especially developed for loose bearing seats and fills gaps up to 0.25 mm. So it might work. But I have no idea how long it may last. You should definitely check out how to remove the adhessive if it fails.
I had one of the first M8xx batch and there was an issue with a loose bearing seat. Florian glued the bearing i just as described. Unfortunately it did not last too log and in the end, Florian had to replace the part with one that had a tighter seat.
A good alternative (but expensive) would be to repair / recondition the bearing seat, may it be with hard chrome plating, plasma coating or whatever.
Anybody have any news for October?
Sure would be easier waiting for them if they weren’t so exciting
Are you referring to waiting for news on eta delivery of latest Schlump hubs? Any news anyone?
