Through axle loosening off?

Hey there peeps.

I’ve seen a few boost rear through axles loosening off all on their own of late. A couple of YT Capras belonging to mates and my own bike most recently. Just standard DT Swiss axles.

Has anyone experienced something similar or have any ideas as to why it might be happening?

My fat bike kept doing it. As it had a separate nut I drilled it (and the axle) and fitted an r-clip.

I have had this on my Trance.

Rear wheel becomes slightly loose yet the thru axle doesn’t appear to have moved.

Don’t have DT Swiss thru axles. Only RockShox and Fox.

But do you mean the “RWS” thru bolt from DT Swiss?

It might be that these RWS things don’t work with “flexible” bike frames. Very stiff, rigid frames: no problems with RWS. “Soft” frames (where quick release works great): the RWS bolts might loosen. Don’t know of any fix.

In my opinion: the RWS isn’t really a good design. But I might be wrong so..

Oddly my boost Stumpjumper rear axle came loose today at fod. But might have been my beer awaited bike fettling last night

andreasrhoen, the rws is no more than a fixed bolt with a ratcheting handle attached. Not exactly much to be bad in that.

@nixie: rws

Yes – it’s a fat, fixed bolt – but nothing there to really “prestress / stretch” a bit.

The thru axles I have on my bikes use all some sort of “securing” clamp mechanism. But the RWS not.

Traditional quick release: they are flexible and have also this securing mechanism. The RWS bolt is “to fat” to get stretched (at least a bit) – but there is no securing mechanism either…

Means when the bike frame flexes a bit the RWS loosens up quickly?

But is the PO talking about the RWS? Not sure.

The RWS thing sounds like what I’m talking about. Simple axle skewer that screws into the drive side of your rear dropout with a right angle handle on the non drive side to let you turn it. Simple through bolt axle in my words. I wouldn’t say a Capra or 5010 is a “flexible” frame though.

I had the same issue with my DT swiss on my Capra. Turns out, from what I can tell, it was the preload on the wheel bearings being to loose. I adjusted it and it hasn’t happened again (about 20 rides or so). Might just be luck though!

Happened to me on my Jeffsy.  I think I just hadn’t done it up tight enough.  I believe the manual advises it needs to be pretty damn tight.  Haven’t had an issue since, though I do now check it fairly regularly (at least before I set off, not necessarily during rides).

I don’t have the RWS on my bikes – but know the RWS from our biking group…

Fox & RockShock : I turn the thru axle in. Not very tight. Then I push the lever in. This lever has to be tight so. Both systems provide ways to adjust “how tight the lever” will operate.

RWS: I recall that there are RWS bolts around with plastic handle and ones with aluminium handle. The plastic handels are not sturdy …

But either way: other than with Fox & RockShox you need to tighten the thru bolt more when turning in…

Capra: Possible to ask YT about this as well? A mess when the RWS has the plastic handle and when you damage this… A mess as well when the RWS comes loose.

(I don’t like this DT RWS at all.)

The DT RWS skewers do it on my Transtion Smuggler and carbon Patrol. They’re still better than having to get an allen key out every time I want to take the wheel off but it is a little annoying.

I had the RWS on my Banshee. I found it easy to knock it loose with my heel.

Swapped it for a Maxle, problem solved.

I have a syntace x12 which is basically just a bolt. In normal guise you tighten with an Allen key however I have the upgrade (hidden Allen key) that means you just turn to tighten. To me this is no different to a RWS but it does not loosen.

In normal guise you tighten with an Allen key however I have the upgrade (hidden Allen key) that means you just turn to tighten.

That sounds interesting.  Tell me more.

https://www.syntace.com/index.cfm?pid=3&pk=2601

Here you go.

I’ve got RWS type ones on 3 of my bikes, one a HT, one a FS and the other a CX bike which also has the RWS type on the front.

I’ve not had anything come loose at all on the HT or the FS (the CX is new) but my other CX had the same fork and I had no issues with that over 1000’s of KM’s between them.