Just thinking out loud, but are there any bent teeth on the chainring or cassette?
Cranks, cassette and chain all brand new. That's why it's so sad :(
@pifko started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
Just thinking out loud, but are there any bent teeth on the chainring or cassette?