Check drive side spin cap.
Stop riding immediately!
Riding your bike with the cassette or chain rubbing your frame will damage your chain, cassette, and/or frame.
The CORE requires the presence of a spacing adapter installed on both sides of the CORE.
When your cassette, or your chain sitting on the highest/smallest cog on your cassette, is rubbing your frame, this normally means that the drive side spin cap (Adapter C) is not installed over the freehub/axle locknut to properly space the frame away from your cassette. When you tighten the thru axle, it pulls the frame into the cassette.or
Original vs updated drive side spin cap.
If you've misplaced/thrown away Adapter C, you can purchase a replacement thru axle adapter kit here.
If you've double-checked the CORE box and bag of adapters and Adapter C was not included please reach out to our support team.
If your concern is unresolved or you have questions, please submit a support request and our support team will be happy to assist you further.