Oval rings.
Re: Oval rings.
IME it's the relationship of the ovality to the cranks that matters, not to the horizon I've had a Rotor ring on the front of my HPV Grasshopper for over a decade, and the only obvious difference with using a plain chainring is the way that with the Rotor ring the chain tube moves up and down as the cranks rotate I used to be able to spin it up to around 130rpm though...
"42"