Rotor Goes Back to the Future with Ovalized Chainrings
No, Rotor claims its product is completely different from the gone but not forgotten Biopace chainrings. A decade ago, they debuted courtesy of Shimano but didn’t last.
Now Rotor is bringing back ovalized chainrings and hopes to achieve what Biopace also set out to accomplish – compensate for the dead spot in pedaling.
Rotor does is differently. The Spanish parts maker’s Optimum Chainring Position (OCP) allows varying the point where the ring resistance is bigger; adjusting it to the moment when the rider applies the maximum strength. A small variation brings up to a 20 degree difference between first and last adjustment points, all within the downstroke.
Rotor offers Q-rings and QXL for road that have 5 OCP regulation points while MTB rings have 3 such points. QXL are Q-rings with greater ovalization. They are a complementary option for those already using Q-rings. They offer 16% ovalization compared to the regular 10%.