So you know Powertap was purchased by Sram/Quarq. I was under the impression they were still servicing the Powertap products even though they were discontinuing them. I reached out to them to get a new set of chain rings for my C1.
This is the reply I received:

Hi Phil,

Thank you for reaching out! Unfortunately, the C1 ring has been discontinued and it's parts are no longer manufactured. I apologize for any inconvenience that this may cause. Please let me know if you have any further questions.

Cheers!


- Heath
Quarq Tech Rep



So my question has anyone replaced them with another brand of chainrings? And if so did it work ok? Mine are 50/36 with BCD of 110. they are made by FSA originally so I have also reached out to them but nothing yet. Does anyone know what rings are compatible? Calibration is not the issue just want to make sure they work and fit ok. Mine are getting close and was going to do this change in the upcoming winter. I was going to send it in and let them do it but that is out so I am wanting to try it myself.

thanks,