absoluteBLACK Chainrings – An Oval Revolution

Unless you are running a 1x drivetrain for cyclocross or multiple disciplines like I am for Project OneBike, you probably don’t think about chainrings all that much. For most people, you get a bike, it has chainrings, good enough until they need to be replaced. Even then, most people probably just replace them with whatever the bike came with. absoluteBLACK wants to change that and get you to join the #ovalrevolution. Over the past few years, I’ve been running their oval rings on a road double, mountain bike 1x, and in 38, 42, 46, and 50 for 1x on Project OneBike, and I won’t go back.

There are three main shapes of chainrings on the market now, round, oval, and well, we’ll call them “other”. Most brands, including absoluteBLACK, make round rings. They are traditional, they are what come stock on your bike, it’s what everyone is used to. Oval rings are what they sound like, a smooth oval shape, effectively changing the ring’s size as you pedal. Two of the most well-known brands for oval rings are absoluteBLACK and Rotor. Then there are other rings like Osymetrics “twin-cam” shape that isn’t oval or round, but also change effective ring size as it spins.

I was always curious about oval rings. I’m not the best climber in the world, and like most other cyclists out there, I’m always looking for ways to help me ride longer, faster, and enjoy the ride more. That’s just part of the benefits that I’ve seen with absoluteBLACK’s oval rings.

My first experience with oval rings was actually with Rotor. I started to see the benefits of riding oval, but I felt like they had some flex when shifting from the small to big ring under power, or when putting a lot of power down in the big ring. That was about the time that I found absoluteBLACK, which looked to be stiffer. I was right.

First up was a set of their Road Premium oval road rings in 52/34 on a Shimano Ultegra 6800 crankset (later a Pioneer Ultegra 6800 dual-sided power meter). Immediately, I could feel the subtle difference between the round and oval rings, but it was very positive. I felt like my cadence was a little higher, my pedal stroke a little smoother, and it felt natural because I could get through the pedal stroke easier. I had to tweak the front derailleur a little to keep shifting crisp, but I was able to dial it in pretty easily following the suggestions on absoluteBLACK’s website (click HERE and scroll down towards the bottom).

When it comes to shifting, most companies use pins on the inside of the large ring to shift up. Instead, absoluteBLACK machines 6 ramps into the back of their large ring to help grip more of the chain to distribute the load better for crisper shifts.

Next up was switching the 1x rings on my Cannondale Scalpel and cyclocross bikes to absoluteBLACK rings. They feature a narrow/wide tooth design to keep the chain from falling off the ring. With today’s clutch rear derailleurs, this was never an issue. In both cases, I felt the same increased cadence and easier climbing, but also better traction on loose surfaces. This is one of the areas that oval rings really shine.

Here’s why. absoluteBLACK’s oval rings reach their largest gear size when you are in your power stroke (think 2 to 5 and 7 to 11 o’clock), and their smallest gear size when you are clearing through the dead zones (5 to 7 and 11 to 2 o’clock) at the top and bottom of your pedal stroke. This helps smooth your pedal stroke by allowing you to use your power at the most efficient points in your pedal stroke, while also getting you through the top and bottom dead zones quicker and easier. Round rings are the same size at any point in your pedal stroke, meaning you have to work harder to get through the dead zones, which makes your pedal stroke not as smooth as it is with absoluteBLACK oval rings. If you have ever had your rear wheel spin-out while trying to climb on a loose surface, this is a perfect example as you are having spikes in power with round rings. aB’s oval rings help to smooth out that power to help you keep traction, by keeping the tension on your chain more consistent.

If you still aren’t sure about oval rings, check out this video. It includes info from an independent study by Dr. Borut Fonda of the University of Primorska in Slovenia. You can read the full study here. Some important statistics they mention are up to 9% increase of force effectiveness, up to 7% less oxygen consumption, up to 15% less ventilation (breathing) and up to 10% heart rate decrease when using oval chainrings versus round.

One thing someone always brings up when I talk to them about oval rings is Shimano’s Biopace. I’m just going to say it, these are not Biopace. Shimano’s oval hits their largest points in the dead zones, which is the opposite of what absoluteBLACK rings offer. Instead of using a cyclist’s power most efficiently, Biopace puts the easiest gear in the power zone, trying to speed you through the power zone and carry that momentum through the deadzones. This makes your pedal stroke more choppy.

absoluteBLACK tweaks the positions of their ovals depending on the type of ring and its intended use. The road products prioritize improved climbing and efficiency. The off-road products prioritize climbing traction. Here are the specifics for a few, with a range covering the various size rings available:

Premium Road Oval – 108-109.5 degrees from top dead center

1X Aero Oval – 108.3 degrees from top dead center

1X CX Oval – 110.5-112.3 degrees from top dead center

1X Mountain Oval – 110.5-116.3 degrees from top dead center

Earlier, I mentioned that my impression of the Rotor rings was that there was a little bit of flex in them. absoluteBLACK rings, on the other hand, feel rock solid. aB’s rings are machined from 7075 aluminum and anodized in various colors depending on the rings. Their rings are also part works of art. The rings have almost a structural design to them that also gives them a unique look. The Premium Road rings have material removed creating a crossed arch pattern, with a textured design in between. The 1x Aero road ring has a spiral design, which looks really cool when pedaling. The 1x CX and MTB rings have sections completely carved out with a textured surface on the materials left.

Prices run from $56.95 for inner 2x rings to $167.95 for the 1x direct mount aero road ring. absoluteBLACK makes rings for all of the major crank standards in 1x and 2x. If you are running 2x, and not sure oval is your thing, I suggest picking up an inner ring first. They work great with round outer rings, and you get to try out the climbing benefits in the small ring.

If you are still on the fence after reading this, absoluteBLACK also runs a demo program through local shops. They have a handful of shops highlighted on their page but find your local aB dealer to see if they have any rings you can demo.

When we review products, sometimes we get to keep them. If it is something I like, I work it into my gear rotation and keep using them, while other things will be given away to friends or sold off. From the beginning, absoluteBLACK’s rings are something I knew I would be adding to all of my bikes. There have even been times that I’ve added the 1x rings to demo bikes for longer, more challenging rides. For me, that is a true sign of whether or not they are are a product that I feel like I can’t live without.

http://www.absoluteblack.cc