I bought a brand new 650b wheelset (well, from pinkbike, never used, but I’ve got no comeback) – DT 350 hubs with EX471 rims. Now bearing in mind the use they get – everything from long XC rides to DH tracks, drops, gaps etc I’m surprised to find that they have 1.8mm plain gauge spokes. I’ve only used them for 5 rides including an uplift at BPW and so far so good. However last weekend my mech snapped and took out 4 spokes. It wasn’t until I came to repair it with 2mm spokes that I noticed. So, can I repair it with 2mm spokes and have a mix of spokes and nipples? I’m tempted to rebuild them with all 2mm spokes as it seems like 1.8mm isn’t really suitable for their intended use. Any advice?

EX471s come with (and should be used with) PHR washers and Squorx nipples to fit 2.0mm spokes, so yes I’d rebuild with DT Comps (2.0/1.8/2.0) spokes and make sure that both the PHR washers and the Squorx nipples are used. The Squorx nipples have a different shape at the rim interface, so that they self align in the washers, which themselves spread the load on the rim bed.

Thanks for the info. They do have squorx nipples, with the integrated threadlock but for 1.8mm spokes. Not sure if they have washers though, although if they have squorx nipples I guess they will. I’ll check later. I feel they should be 2/1.8/2 double-butted though as you say

Odd – they come supplied with 2.0mm nipples. Has the guy you bought them from still got the 2.0mm nipples that they came with?

You sure they haven’t just got really short butts?

Or is the builder a bit of a plonker.

He removed them from a brand new bike (I think), so an OEM wheelset. The DT Swiss logo has a grey surround as opposed to red. I’m going to drop him a line in a bit just to see if he has any more information. So if I get some 2mm squorx nipples and double butted spokes, do I definitely need the PHR washers too?

EDIT: Just downloaded the DT Swiss user manual and it clearly states to include PHR washers so I’ve fielded that question myself 😉

Try and do things on the cheap and you end up spending more in the long run! Should have just used Merlin or Moonglu 🙁

They/you don’t have to use Squorx nipples, there’s various DT nipples options that are the same shape. An OE set would probably use DT Pro Head Doubles if they had their head screwed on right … they went with Squorx which is fine too, but they do need the washers. They are basically in lieu of a thicker spoke bed and so you weaken the rim alot if you don’t use them. They may well have done though, peel off the tape and take a look in a spoke hole.

Would I have used 1.8 PG spokes? No. Would I be overly concerned? Also no. Its probably as likely bad luck that you snapped 4 spokes as any fundamental issue. Sounds to me like they wanted to save weight without the associated costs of a heavily swaged DB or TB spoke.

Was going to say.. If the mech meets the spokes at any kind of speed it’s going to snap a few, regardless of what they are surely?

Thanks very much Ben. I’m toying with the idea of checking they have the PHR washers and just getting some 1.8mm spokes and rebuilding as is. I am a little concerned though as I’ve been known to land a little heavily once in a while on road gaps etc and I really want to have that peace of mind.

I agree with you and matty that the snapping of the spokes isn’t related to the diameter, I was just unlucky that the mech took them out. I just mentioned it above as that’s what prompted me to replace them and hence how I noticed.

Re nipples – any with the spherical contact surface are good for these. Not standard DT Alu or brass ones that come supplied with spokes.

The Squorx, Hidden and Pro Head models all have the spherical interface, but the Squorx ones make it easier and faster to build which is why they come with them rather than the other compatible models.

It wouldn’t bother me regarding the spokes, and my use sounds similar to yours.

The spoke breaking reality is you smashed a mech into the wheel, something was going to give!

If you want to replace them with something more fancy, go for it, My rear wheel has 2 sorts of different spokes in & it’s still round & true 🙂

IME they work fine with normal brass nipples too (+washers).

Next dilemma (if I decide not to rebuild with 2/1.8/2) – where to buy 1.8mm PG black spokes at 272mm length?

Yeah good luck with that probably straight pull too? If you struggle dt super comps will work with the 1.8nipples you have and hopefully you can reuse or get new pro head nipples with them.

Thanks again Ben, good shout on the super comps. Going to get a few quotes to have them rebuilt I think. I can repair and do a bit of truing but a complete wheel-build could get me in all sorts of trouble 🙂

I’ve only seen one OE set of wheels that’s not plain gauge (hats off to the Genesis CdF one of my colleagues bought). I would run them until the spokes start to break (without the mech smashing into them) then replace the spokes if everything else is still in good shape.

For all you know you might massively mess the rims up a week after you’ve rebuilt them, and the plain gauge spokes will only significantly impact the fatigue life, not the strength of the wheel itself.

Probably easier to find 2.0/1.8/2.0 replacements so just remember to swap nipples out as you go, and if you do have to rebuild don’t confuse yourself by trying to reuse anything.