I had this happen to two DZero units last summer a month apart. Both had to go back to Quarq for replacement. The first chain drop didn't show any evidence of damage to the spider, just the super high reading. It was a solid drop so I kind of wrote it off. The second unit failed when the chain fell off the inside of the front ring after I cleared a twig out of the rear derailleur by pushing the cage forward to remove tension. I could hardly believe this one. This worries me on the longevity side of things.

I've had/have 3 other models of Quarq powermeters - the early S975's, Elsa R's and the Elsa RS's with not one failure or even issue with any of them. To have the new DZero fail twice in two months total use was disappointing.

We have seen a very small number of failures related to excessive impact/off-axis loads to the spider that, in some instances, can result in an unrecoverable calibration error.

Corrective actions are being taken to prevent this failure on current production product.

As always, please contact me or our customer service team for for any trouble shooting or questions you may have regarding your Quarq product.

jesse@quarq.com

thinkfast@quarq.com

1-800-660-6853
1-605-642-2226

is it a software amendment or a physical change?

Undetermined at the moment but more than likely it will be a process change during production.

Any update on this? My carbon GXP Dzero is a month old and the chain got caught on the inside near the bottom bracket this weekend (I have a chain catcher that caught it on the top side). The offset went from ~100 down to -500 and then -5000. I tried recalibrating and pulling the battery multiple times to no luck.

I've had a Red 22 Quarq for about 4 years with few issues and been happy with Quarq's customer service. Disappointed with this one so far.

I have an email out to Jesse and Quarq but haven't heard back yet.

They will probably end up sending you a new unit as I don’t think there’s a solution. Sorry for the headache. Very frustrating. I’m on my third unit since Dec 2017 :/

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Toro Performance

I think this just happened to me. Does anyone have a simple fix, or is the hardware toast???

I can't believe a chain drop can break a PM like this

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"What the mind can conceive and believe, the mind and body can achieve; and those who stay will be champions."

Unless they’ve changed their service model, it’s as simple as giving them a call and then sending it back for free replacement.

Well, seeing as this thread got revived, I guess I'll chime in. I had just installed a Quarq DFour91, and I downshifted the front on a gravel climb. The chain came off to the inside and after that my power readings went way off, then went missing (although cadence still showed). Basically, same issue as the OP.

The fix was that Quarq did set me up with a DFour DUB, a DUB BB, and the nice new carbon arms, since I had bought a bunch of PF30/BB30 hardware. The Quarq person described this as a freak accident. At the time, I wondered how it was that the first rep I got on the phone had heard of the issue if it really was a freak accident, but I guess there are a number of Quarqs out there. I hope this issue has been resolved on the new DFours. I would definitely not like to break my Quarq after the warranty expires. Hopefully they'd at least offer a discounted unit. Best of luck to the more recent victim.

Damn. Well, yeah, not a freak accident. But I am glad you got a new unit.

I sold my DFour91 w my old bike and I am onto the DFour DUB unit without any issue. *knock on wood*

Thanks for chiming in.

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Toro Performance

Heaven forbid that you should knock the DFour on wood...

I'm sorry. I couldn't resist. I'll see myself out.

Welp. Now its broken. Thanks. 😂

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Toro Performance

Well, I will join the club with a failed Quarq Dfour. Although I did not have a chain drop while riding, all other symptoms are the same. No power reading, offset of -32000 and still cadence. I read in this topic that Quarq acknowledged the issue and changed production processes in 2018, unluckily my unit is from prior 2018. I had contact with Quarq and I also pointed out that it was a known weakness by them of the first generation Quarq Dfours (evenly stated by themselves in this topic) and that, although I ran out of Warranty, I would very much appreciate if they were not to strict with their 2 yr warranty in this case, since it was a known and acknowledged weakness.
Their respond was quiet clear: We can not do anything for you and although Jesse acknowledged the problem we can not extend warranty service to you. And furthermore they quoted the warranty that in addition to the duration of the coverage of the warranty, warranty does not apply when products are incorrectly installed or damaged caused by a crash, impact or abuse. Implicitly they are implying: well, you f*cked up, it's not our problem. They didn't mentioned anything about a replacement or so fort, just sh*t up. That leaves me here with a $900 cadence sensor on my bike...

To be honest; I am really disappointed in Quarq with their responses so far. I bought the Quarq also because of their known reliability and if sh*t happens, they were well known for their customer service. For now, it just sucks that it was not reliable and also their customer service was not helpful.

On one hand, they are within the terms of their warranty.

On the other hand, this is a known issue, and if you spend $900 on a power meter you don't really expect it to be obliterated by, of all things, a dropped chain. Who here has never, ever dropped a chain? It would seem reasonable to offer a discounted replacement, at least.

I had the same issue after a dropped chain on the trainer (had a chain catcher - still didnt help).
Spoke to SRAM on the phone - I am in Australia - head office here is just around the corner from me.
They initially said that my issue was unusual - told them it wasnt.
Had to go through my LBS with a report. LBS sent it in. They only send the spider back through a LBS.

Considering mine was out of warranty (and i was the second owner - mind you they never specifically asked if i was the original owner).
Got offered a new one at a 'crash replacement' price - $500 AUD - half price a new one. Was the best they could do.
Have to admit the customer service i got here was really good.
Maybe write a 'nice' letter/email with support or follow up from your local bike shop.

Yes,agree, with you two above. I though at least they could search with me for a solution, instead of the solution being: Just buy a new PM. The expected lifetime of a powermeter is at least 5 years in my opinion. Dutch law has special warranty law, that if a product defects within the period of which it is reasonable to assume that it is within the lifetime of a product (i.e a washingmachine has a longer lifetime than a pen and is based on a) type of product, b) price) and if the user can proof that he used the product as described by the manufacturer than the manufacturer should come up with a solution (ie. repair). [url=https://www.europe-consommateurs.eu/...Country_fiche_NL.pdf]more info[/url].

I have send another email to Quarq if they would review my case again and think with me on a solution, since now communication is quiet binary. I say they are at fault, they say it's just out of warranty. Hope we will work it out together!

Another thing about that. I was concerned when I called Quarq that they'd say sorry, you damaged the PM in regular use, so there's nothing we can do.

Fortunately, this didn't happen. Power meters are obviously not invulnerable, and nobody expects them to be invulnerable. But dropped chains are part of cycling. Who here has never dropped a chain? Had Quarq told me to go eat cake, we would have been hearing about it here, let me tell you.

They're obviously not obliged to support units from the beginning of time until the end of time, but this was a known flaw, and I would at least cut you some sort of crash replacement deal.

Yeah, the issue I think is that the power bits of the spider close the gap near the frame, and so where a 'normal' dropped chain isn't too bad as it lifts back off, with the Quarq spider it closes the gap to fractionally less than a chain width and so then gets jammed between frame and spider. Having experienced this myself then there's two factors. One is the specific BB/Frame combo that means this can happen and the force that gets loaded. The second is how you get the chain out. If you are able to unbolt the chainset, lift chain out and reattach you're all good. But if it happens mid ride and you yank it out then bad things happen as it's putting forces on the spider in directions that they were never designed to withstand.

And that last part is the nub of it. In many places in the world consumer law has some 'fit for purpose' protection. And the question, as raised above, is if it should have been designed to withstand a side load. Just as many powermeters struggled with water ingress, where it was clear that they needed to be designed to cope with damp/rain/sweat, it's not all that unusual to expect that over the life of the chainset it would expereicne a chain drop.

That's terrible support for a product that had a known design flaw. They should be doing a recall on all of the units produced prior to them "fixing" the issue.

Hi guys, thanks for your support! I can imagine that they don't want a 'recall', also since it is not a structural issue, there is no risk involved using the product. Of course, most users don't have problems. But, I think it is a functional issue for some who run into problems. I had a bit of the same 'issue' one time with a Garmin GSC cadence/speed sensor. They also were 'known' that problems could arise with the speed part of the sensor. A simple email to Garmin with the problem was enough to get a replacement. No further questions asked, and the item was, just like Quarq, out of warranty.

Well, last Saterday I did send Quarq another email to see if we could come up with a solution together, have nothing received back from them. Keep you informed, and if anyone has a 'golden idea' please let me know!

Have you tried calling rather than email? I got quicker responses that way.

I would also point to this thread.

I was lucky enough to to be in warranty when this happened, and it gives me pause to buy another quarq if they have no consideration after warranty. It is a known flaw. Dropping a chain happens pretty regularly for folks.

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"What the mind can conceive and believe, the mind and body can achieve; and those who stay will be champions."

My DFour Dub just failed also due to a chain drop... Time to call SRAM on Monday.

With apologies for the thread resurrection, but this seems to be one of the most prominent thread on this topic.

After 6 years, one of my 3 Quarqs has just had the dreaded chain drop situation and become a very expensive cadence meter. Whilst my powermeter is well outside of its warranty period, I'm slightly peeved that this is a known issue and one which Quarq decided not to do anything about. Has anyone had any success with Quarq well outside of warranty?

Had I dropped a chain within 2 years, it would have been covered by warranty and I'd likely have ended up with a better-designed unit, but as it is, my ability not to drop the chain (likely because it's on my TT bike and therefore rarely changes chainrings on the front, as well as only really being used for half the year) means I'm likely to be forking out for a new unit (and of course they no longer make the DZero GXP, so new unit means powermeter, cranks and bottom bracket!).

There’s no difference between the Quarq spider mounts between spindle types. There is now a slight offset difference with the DUB spiders of approx, 1mm. I haven’t seen anyone report an issue using old/new offset parts together. So you should be able to just pickup a new DUB spider to match your current rings and make the swap.

Also never hurts to see if Quarq will do anything for you. Prolly not as SRAM version of Quarq and Zipp CS lacks everything that made CS special at these companies:(