Sram rear just ‘exploded’ – what do I do??

I’m no bike mechanic, and this SRAM rear set up is all new to me. Canyon Neuron CF9 AXS, DT Swiss XM 1700 on 350 hub.

Taking the chain off to clean, and took rear wheel out of bike. Large clang and the cassette and these bits are on the floor. Help please…I’m meant to be away on Monday for 4 days biking.

The good news is, that all pushes on so easy to fix. Bad news is, I’ve no idea the order it goes on!

You’re freehub likely has nothing to do with Sram.

spring > ring > ring > spring and shove it back on again. Then carefully have a look to see if there’s anything wrong with the hub and freehub (taking the cassette off would be a good idea).

What hub is it? There are a lot of designs that the freehub just pulls off of. Thought the days of them just falling off were long gone though

DT freehub has dropped off the axle – they can do that. Make sure there’s no grit in the exposed faces then put a spring over the axle, then a ratchet with its teeth facing out, a ratchet with teeth facing in (so the ridged bits are together), then the other spring. Then push the cassette back onto the axle until it seats.

If you have a cassette tool to get it off the freehub that makes reassembly a bit simpler, but it’s doable either way.

Get an exploding diagram of the hub (and its freehub). What make is it?

Fear not. They do this, perfectly normal, its a feature. Just slide it back on the axle, ratchets teeth together, sandwiched between the springs with wider ends facing the bearings. It would be an ideal opportunity to clean everything, but best to only relube with the dtswiss grease specially made for this – its especially non-sticky type to ensure proper ratchet springing – but yours looks fairly free of grime anyway so I wouldn’t bother.  Usually the small seal on the end of the endcap beneath the cassette end holds it in place to prevent accidental pop-off the axle… I often pull the whole cassette/ driver off just like this to clean as its easier than wrenching off the cassette…

Israel’s new MO ?

The cassette won’t push back onto the axle. I’m stumped.

If you look through the freehub has the spacer between the bearings moved so it’s now in the way?

There is a spacer sleeve as well and hat will inside the freehub attached to the cassette. Try and either fish this out and push into axle first or just centre it in the hole. If it’s off centre the axle won’t go through.

Cheers @mashr seems that was it. Any way to ensure this doesn’t happen before I go away, or, is it okay once in the bike held in place?

As I say, I’m no mechanic, nor particularly mechanically minded. Help much appreciated STW. Thank you.

Yup it’s all held in place when it’s on the bike. Hadn’t appreciated that (despite owning one) DT Swiss have a habit of doing this.

Just give it a spin when back together to make sure it sounds like it should. If all sounds well then you should be grand

As above. It should probably look something like this and should just press back together by hand.

Here’s a video that might show it clearer.

Normally the bolt through holds everything together. I’ve pulled mine off with the chain once. Obviously when I wanted to actually service it, it was a pain to get off. Because I don’t want to loose the bolt through and I’m a bit nervous about losing bits in my car if it came apart I put the bolt through the hub when packing it so at least if things do come apart they are likely to stay together.

@jonba that video is really useful thanks. Appreciate the help folks. STW to the rescue yet again. Reckon this place does more good for those of us with paralysing GAD, than pills and potions!! (laugh emoji) (well, as long as you stay away from politics threads…and covid…and what tyres threads…and…)

When transporting DT rear wheels, put a length of string or wire through the rear axle and bind it down to prevent accidentally dropping the cassette and hub internals on dirty ground. Same thing when doing a tubeless install or anything with the rear wheel. Bind it down to avoid trouble. The end cap is all that holds the cassette and freewheel to the hub, just a little o-ring is all that keeps it on!

And it may be a good idea to – bind it – even when doing a tyre job off road – not much fun to loose a ratchet ring in the woods, 15 km to the trail head. I always tell the customers this too – have a length of string with you!

Just be aware.

The springs must be orientated with the tapered end (smaller diameter) towards the star ratchets as shown in diagram above.