I've struggling for a while with ripples that show up in the side of my prints. I've started printing simple hollow cylinders because they showcase the problem well and print fast for faster troubleshooting but I feel like I've been getting nowhere on this issue no matter what I change. I've tried lowering the jerk and acceleration thinking it might be a case of ringing but it didn't make a difference. Adjusting extrusion multiplier has an impact but I haven't yet been able to solve the problem with it.

For extra info, I'm using a custom bowden printer, abs plastic, and a 225 C nozzle.