Anyone got a DT Swiss 240/350 Microspline Rear Boost Hub? Please read...

L.P.

Likes Bikes and Dirt
Normally when you get binding (and a hub that measures <1mm than it should) its because the spacer between the freehub and hub body bearing is missing. But in the first pic its there. You sure you didnt remove it when cleaning it up and reassemble without it? It should be 15.4mm wide.
 

Shredden

Knows his goats
Normally when you get binding (and a hub that measures <1mm than it should) its because the spacer between the freehub and hub body bearing is missing. But in the first pic its there. You sure you didnt remove it when cleaning it up and reassemble without it? It should be 15.4mm wide.
This was my first thought, and I was really hoping that it would be the case. But I definitely have it - and I've had a look at the exploded diagrams online and confirmed I'm not missing any other parts.

edit: should add that i've measured it and it's 15.4mm. i've also confirmed that the hub binds up with and without the star ratchet and springs installed, to rule out anything silly like having a spring jammed in there incorrectly
 
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Shredden

Knows his goats
Thanks guys for the suggestions RE shimming it - i'll definitely try that if I can't find another solution. But if there's a part that will resolve it and keep it all legit i'd prefer to try and get that to work.

The reason it is binding is that the rear drive-side end cap has the step machined too far in for some variations of DT Swiss Hubs.
That certainly seems to be the case here, did you ever get to the bottom of exactly why it is like that?
 

Nambra

Definitely should have gone to specsavers
Did a bit more googling and ame across this link via the Roval wheel thread on mtbr:

https://r2-bike.com/DT-SWISS-Freehu...-12-speed-12x142-mm-12x148-mm-BOOST-Thru-Axle

It appears there are two variants of the DT Swiss micro spline freehub, the one in the above link has no widened flange on the hub side. This version apparently works with Roval wheels. You’d think that either freehub variant would work with DT Swiss’ own hubs, but it seems some people have had to machine the widened flange off their MS freehubs to get them to work on 240s/350 hubs.

If indeed there are two versions of the freehub (with the same part number too) then you might have to contact Apollo Cycles (DT Swiss distro) to see if they can’t help out with an undisclosed incompatibility between DT Swiss’ own products. It seems that if you want to keep your hub “standard” (I would too TBH) then you may need the alternate freehub body without the flange. It will be interesting to see if @ozzybmx has any issues when his parts turn up.

The bush fix shim is probably going to work well too as it’s likely to be fractions of a millimetre in clearance - it certainly won’t cost you much to at least try. I did something similar with an old DT Swiss Onyx (2 pawl) hub - I had to replace the freehub body and the new one had a thicker seal around the outboard bearing which fouled with the end cap flange. 0.4mm of coke-can shims sorted it out.
 

L.P.

Likes Bikes and Dirt
I'd suggest it isnt only freehub compatibility. This is because DT Swiss hubs measure exactly their intended width. Yours should measure 148mm exactly (within .05mm). So there is something within the spacing on the drive side that is incorrect.

Certainly Roval hubs have compatability issues with microspline (Roval wanted their hub flanges closer to the drive spokes than on normal DT Swiss hubs, taking up the same real estate as what the microspline driver now wants to take up), but this isnt your issue. The Microspline Roval compatability issue occurs when the ratchet seal (the bit that presses in to the hub shell in the first pic) is recessed further than flush. it isnt on your 350s.

I dont know what to try next but its certainly unusual.
 

bear the bear

Is a real bear
Thanks guys for the suggestions RE shimming it - i'll definitely try that if I can't find another solution. But if there's a part that will resolve it and keep it all legit i'd prefer to try and get that to work.



That certainly seems to be the case here, did you ever get to the bottom of exactly why it is like that?
My saga was the freehub and end cap I purchased off EBay worked for about 6 months then started to bind as yours has. After a bit of research and checking that the sleeve was as per the DT Swiss Spec, I worked out it was the end cap as it would bind with the thru-axle being done up. I purchased a new endcap from MTBDirect thinking this would solve the problem but it didn't. So, I ended up selling the wheelset and buying a new set with the microspline freehub. I didn't have any shims available and the local machine shop has a minimum $120 charge for any work, so this was the easiest solution.
 

Nambra

Definitely should have gone to specsavers
@Shredden, sorry to get all nerdy but as this may affect others, it might be worth trying to isolate the actual issue for everyone's future benefit, particulalry as Shimano 12-speed is becoming more widely used.

Are you able to confirm some dimensions of the MS freehub, per the sketch below. In particular, dimension A (probably easier to calculate as B minus C) and diameter D. I can do the same measurements with an XD and/or HG driver when I get home this arvo (unless someone else can contribute these dimensions sooner) and we can compare them.
  • Dimension A is the of interest as it will tell you if the inboard bearing is recessed in deeper in the MS freehub compared to an XD and if so, would confirm that shimming the internal 15.4mm sleeve (or getting a slightly longer one made) is a viable solution. If you're shimming to get the same A dimension as an XD driver, then you probably won't be increasing any gap between the freehub dust seal and the hub shell any more than it is with an XD driver (so you're not increasing the likelihood of contamination).
  • If the A dimension is the same it would suggest that it is the outer flange on the MS freehub that's the culprit and why dimension D is then of interest.
As @L.P. says, the overall width of the assembled hub should be very close to 148mm and your measurement seems less than what you'd expect given the tolerances involved. That would indicate that either dimension A is in fact larger in your MS freehub compared with an XD freehub, or that the overall dimension E from the inside bearing to the end of the end cap is smaller on the MS setuo. We could measure and compare dimension E between the two freehubs as a side comparision. However, the binding between the freehub and the hub shell would suggest that dimension A is more likely the issue.

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Edit: Measured dimensions for an XD freehub: A = 5.6mm, B = 8.3mm, C = 2.7mm, D = 37.26mm, E = 41.2mm
 
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link1896

Mr Greenfield
Shredden, my lathe time is paid for in multiples of 6 packs, I'm in Northcote.

Nice drawing Nambra, yours?
 

Nambra

Definitely should have gone to specsavers
Without reading back...you need a boost XD 240? I think my mate is selling a new one.
Not quite - Shredden wants to compare his micro spline driver with an XD to try to work out why it is fouling with his hub (which he purchased as XD but since sold the XD freehub).
 

Isildur

The Real Pedant
I just discovered the same thing this evening. I purchased a MS freehub off Facebook thinking it would of course fit my DT hubs (of which the stable is full of).

First bike I tried it on bound when the axle was done up. Admittedly, the wheelset a non boost 2016 set. But, tried it on a 2018 boost set and still no bueno. And then again on a 2020 350 set, still no go.

So, before I send it to Nambra with a 6er, what kind and where do i put the spacers?
 

Nambra

Definitely should have gone to specsavers
I just discovered the same thing this evening. I purchased a MS freehub off Facebook thinking it would of course fit my DT hubs (of which the stable is full of).

First bike I tried it on bound when the axle was done up. Admittedly, the wheelset a non boost 2016 set. But, tried it on a 2018 boost set and still no bueno. And then again on a 2020 350 set, still no go.

So, before I send it to Nambra with a 6er, what kind and where do i put the spacers?
If you want to help us all out, do you have a Vernier caliper and can you confirm the dimensions A through E in my earlier sketch? It’s the A, B and C dimensions that are of most interest, the overall hub width including end caps would be handy too - to see how close you are to 142 or 148mm.

As far as the spacer goes, I’m thinking that you essentially need to make the “15.4mm sleeve” in my sketch a fraction wider, perhaps up to 0.4mm give or take. Confirming the dimensions of the freehub will tell us if adding spacers will compromise the dust seal between the freehub and hub shell.

This is the 15.4mm sleeve - DT call it a spacer bushing:
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Edit: The DT Swiss Techbook 2020 also indicates that the Microspline freehub is not compatible with non-boost straightpull hubs, only classic, while all boost hubs are fine.
 
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Isildur

The Real Pedant
Ah, reading through this is was @link1896 who mentioned machining - late night phone research after a couple of beers will do that. In any case, I'll measure it up tonight as best I can. I've got calipers so it should be fairly accurate.

It definitely seems to be the fact that this one has a big lip/flange on it, compared to others I've seen pictured with no flange. Doing a direct comparison to the XD driver that came off the hub, there's a lot of extra diameter on MS driver. The MS driver also won't "stay" on the hub axle the end cap is installed and clicked in. Both the XD and HG spares I've got basically self settle without the end cap, the MS pushes back out.

I knew of the SP Non-Boost incompatibility, but that's not the case here. The wheelset it's going onto is a DT 240s 6-Bolt non-boost from 2016 or so. I do have a SP 350, but that's boost from last year.

But, as it was bought from FB as a new-bike take off, I can't see DT being happy to facilitate a swap. Might be worth the question though! But, I think machining the flange off might be about the only option...
 
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Isildur

The Real Pedant
Okidoki. So excuse the short notes and lack of formatting here, but my other half's laptop died so, of course, I'm on my phone while she has the laptop for editing!

There's definitely something up with the interface of this flanged freehub I've got. I've played around with the two wheels easily accessible, a 2016 built 240s 142x12 CL and a 2019 built 240s 148x12 6-bolt, both of which should be fine according to compatibility charts.

Apologies @Nambra but my calipers are a bit too simple to get all the internal and differing measurements you wanted (they're the basic Kinchrome digital from Bunnings), but they did highlight that it's definitely the MS freehub.

I've copied all my measurements below, but to sum it up, both Hub axle spacers were fine, the hub widths using XD and HG drivers were fine, while the MS driver pushed the widths out about 2.5mm on each Hub. I think this can be attributed to the freehub lip not extending past the flange, compared to the XD driver - a comparison pic below with the flat base of each driver lined up (again excuse the dodgy late night shed photo!).

Non Boost
Hub with XD - 141.9mm
Hub with MS 144.6
Spacer 15.4

Boost
Hub with HG 148.05
Hub with XD 147.9
Hub with MS 150.6
Spacer 15.41

20201207_221614.jpg

I didn't even need to install a cassette, with the MS driver on each, when installed into the frame and the axle done up, it bound immediately. What's happening is that the bottom of the freehub is binding on the hub shell as the axle is tightened, as it's not recessing into the hub seal correctly.

Spacing out the freehub might work, but that's then going to leave the internals open to the elements, definitely not a path I want to take.

I'm totally stumped and really the best idea I can think of is to either find the flangeless freehub or get it machined. I can't believe there are two versions with essentially the same part number. I'll probably have a chat to Apollo or Dirt Works tomorrow to see if they have any thoughts.

I haven't seen anything like this in quite a while! I've got an entire stable of DT hubs (6 of 9 bikes with either 240 or 350 hubs) and the idea was that they were all interchangeable with components. I guess that still stands as it seems to be the freehub that's out of spec, but I'd like to figure it out so that in future I can know that all my drivers are usable on each bike.

Any insight you all can provide I'm open to!
 

Isildur

The Real Pedant
I'll also add that if anyone (aka you @Nambra) wants to do some forensic measurements, I'll happily send the freehub over. Given that, well, right now, it's useless to me as is!
 

Nambra

Definitely should have gone to specsavers
So looking at your MS vs XD freehub photo, the difference around the flange area is fairly obvious isn't it. It sort of looks a bit different to various pictures of MS freehubs online as well - the sealing end in the image below looks more like your XD freehub @Isildur.



370221


Your freehub appears to have a little ridge on the side facing the hub too - makes me wonder if you have a genuine DT Swiss part or maybe it's a different OEM brand freehub that uses star ratchets (eg. Specialized, Trek, SRAM)?

370222


The fact that it doesn't fit a 2016 or 2019 240s hub is strange too - the r2-bike freehub without the wider flange hints at it being for hubs newer than 2018, so maybe the wider-flanged variant only works with older hubs (post #4 in this mtbr link supports this assumption too). You report that this freehub fits neither of your 240s hubs, and it doesn't resemble the DT Swiss freehub visually... not genuine DT?
 

Isildur

The Real Pedant
@Nambra yeah that a solid difference. I've asked the seller I grabbed it from where he got it from and what bike it was used on, so I'll update once I hear more...

@Shredden Can you take a photo of the flange/bottom of your freehub? It'd be interesting to see if yours is the same as mine (which is what I suspect) or whether the seals extend as per the stock photo Nambra posted...
 

Isildur

The Real Pedant
The more I look at those pictures (and some others online), I'm thinking that for whatever reason the driver is missing the seal setup completely. The seller I bought it from just came back pretty quickly, he bought it on FB also, but figured his compatability issue was that he was using it on a Non-Boost CL hub (which is apparantly a no go, although I've seen some reports in the last few days of people making it work with jiggery pokery).

I'll still get in contact with DW and/or Apollo to see if they have any thoughts. Or trawl through some German bike sites that are laden with all of the weird spares to see if the seal/lip is something that can be found.

@Shredden I'd still love to see what the flange/seal arrangement looks like on your MS driver!
 
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