Why do people riding rings between 28 and 36t get to have all the nerdy fun?
Oval or elliptical chain rings aren't going anywhere, and for the right person, they make a bigger difference than you'd expect. After having an oval ring on my fat bike two years ago, and sticking with it onto my "Iceman Special" Balthazar, I got a hold of Absolute Black to try out their oval ring for my Kona Private Jake cyclocross bike ahead of the Cyclocross State Championships. Even in the mud, it worked perfectly, and I've stuck with it ever since.
The next idea was 1x road, opting for a 50t Absolute Black Aero ring with an 11-32 cassette, flicked over by a SRAM Rival 1 derailleur. The combination was road-ready, but I had a lingering test still to do. After seeing and hearing about one of my favorite riders, Brad Wiggins, Chris Froome and other pros using oval rings, I wanted to see how a 2x set up would work. More and more tech nerds were doing some digging in the pro peloton, with a growing number of riders using ovalized chain rings as their little ring, which can't been seen and keeps their equipment sponsors happy.
And it is on the climbs where the ring makes the biggest differences. For WorldTour riders, epic climbs at upwards of 10% are more efficiently tackled with the oval ring, and the combination of a more traditional 53 outer ring and a 36t elliptical chain ring seems to be the go-to ratio, usually with a 'compact' 11-28 cassette on big mountain days.
What that tooth count really means is more important. All manufacturers state that the actual feel of the ring is two bigger on the power part of the pedal stroke, and two smaller on the weaker, or dead, part of the pedal stroke. So that 36t inner ring feels like a 38t when you're under power, but turns over like a 34t in the opposite part of the stroke, when you aren't as capable of putting out as much power.
That is a pretty general range of perceived power, and its achieved by varying degrees of ovality. Absolute Black changes their ovality based on the chain ring size, ranging from as little as 6.5% on a 34t inner ring and 11.4% on the 38t inner. The outer rings are closer to the 10-11.5% ovality.
What ring are you? As always, we recommend nerding out on our most visited website to find out what your gear ratio would end up being, using the actual tooth count of the oval ring. I have stuck with a 50t oval with a 36t inner ring. I spend 98% of my time on the outer ring, and I tend to spin a cadence around 90rpm. To me, this is where I've noticed the biggest difference in the oval rings, foot speed. Assuming you're in the same gear, I can spin 4-6rpm faster with an Absolute Black or Wolf Tooth ring. That 4-6rpm translates to more distance, because I will literally cover more ground in the same time. By my inexact calculations, it's 3-4% more distance. That sounds small, but 3-4% over two hours, it can add to up minutes!
Below, I've listed the bike and ring size for each of my bikes. Maybe it will help YOU get bent out of shape.
Kona Private Jake: 40t Absolute Black Direct Mount
Bearclaw Bicycle Co. Balthazar: 34t Wolf Tooth CINCH Direct Mount
Focus Cayo Disc Rival 22: 50t/36t Absolute Black 110 BCD (Spider)