TheBurgtec Oval ThickThin 104 PCD Chainring come after a year full of testing to ensure this is the best chainrin possible. This shrank the dead spot suitably and gave the same flawless chain retention and silence as our round rings. The shortening of the dead spot on the top and bottom of the power curve allows you to get back into the power phase of your crank rotation sooner. The benefit of this is twofold; increased gearing on the downward stroke and faster crank speed to get the crank propelled back around into the power phase continually. This is a significant gain because virtually all studies into pedalling performance suggest that a minimum 80% of your power comes from the down ward motion ... More info