One of the most controversial topics in cycling is the debate over round vs oval chain rings. While round chain rings are still the most common and popular design, oval chain rings have rapidly gained and lost popularity over the years. absoluteBLACK claims to have a proven solution with their oval rings and studies to prove their effectiveness in improving pedal efficiency and smoothness rather than claiming power gain. For SRAM 110/5 cranks, the retail price is $125.95 for 50 / 52 T outer rings and $59.95 34 / 36 T which is actually lower than the price of OEM SRAM Red chain rings. As with all of absoluteBLACK’s products, the chain rings have an anodized finish with eye-catching CNC machining on the face with diamond and triangular cutouts.
The absoluteBLACK Premium Oval road chainrings combine a highly refined oval shape with beautiful anodized CNC construction.
| Retail Price | $59.95 (34/36T) / $125.95 (50/52T) |
| Rating | 9.0 / 10 |
| Measured Weight (in g) | 121 (50T outer), 31 (34T inner) |
| Likes | + Beautiful CNC detailing and anodized finish + Competitively priced compared to OEM chain rings + Smoother pedal stroke while climbing |
| Dislikes | – No color options aside from Shimano PVD version – Outer chain ring requires adjusting front derailleur |
| Where to Buy | absoluteBLACK |
UNBOXING
While most chain rings come in nondescript cardboard packets, absoluteBLACK puts each chainring in a beautiful green packet with gold lettering and intricate cutouts that show off the chain ring inside. Even the paper itself feels like thick premium paper stock with a subtle texture. Inside the packet you simply have the chainrings with only one bolt included with the outer chain ring as you’re supposed to re-use your existing hardware.
FIT & FINISH
Unlike many oval chain ring companies in the past which have promised performance gains, the absoluteBLACK oval chain rings only claim to improve effectiveness and reduce fatigue. Their extensive research and development has resulted in a unique orientation (i.e. timing) and size-specific ovality rating. For example, the 50T outer ring has a 10.3% ovality while the 34T inner ring is 6.5% with timing range of 108-109.5 after top dead center. This has been tuned for road climbing to reduce fatigue and optimize pedaling smoothness. You can see that this effectively makes the chainrings have a larger diameter at the top of the pedal stroke and a smaller diameter at the center point.
absoluteBLACK has also made the aluminum chainrings more unique with their CNC detailing that adds diamond and triangular reliefs to the chain ring. On the backside of the chainring you can also see the CNC detail work with ridges along the chain ring edge and the angled protrusions to help with small to big ring shifting. The chain rings are only offered in a black anodized finish but for some Dura-ace and Ultegra applications there is a stunning PVD (physical vapour deposition) rainbow finish available. We have the SRAM version here to install on our SRAM Red eTap bike but absoluteBLACK offers a wide range of options for any drivetrain.
For 2x road bike setups you can change both rings to oval or mix and match as the most effective use of oval chain rings is in the smaller climbing gears. Installing the chainrings is as easy as unbolting your existing chainrings and re-using the bolts over to the new one. As with any chainring installation, it’s always recommended to use a new chain as the previous chain may have been deformed to fit the old chainring. The chainrings are offered in multiple sizes with 50 and 52T options for the outer chain ring as well as 34 and 36T for the inner chainring.
At slower speeds you can feel a bit of a smoother pedal stroke thanks to the oval shape as it helps minimize the typical dead spot in your pedal stroke at the top/bottom of rotation. Once you gain more speed it’s hard to notice any difference at all from a circular chainring. After some miles it’s easy to forget you even have an oval setup, even with our outer and inner chainring swap. For us, it wasn’t a drastic difference compared to circular chainrings so it’s not something we’d personally do on a new setup. However, if you already have worn out chainrings, the absoluteBLACK chainrings are visually stunning and the slight improvement can help reduce fatigue on longer rides with climbing. We felt like we shifted down less often while climbing with the oval setup and were able to more easily maintain higher cadences.
ON THE ROAD
We installed both the 50T and 34T inner ring onto our Specialized Tarmac with first-generation SRAM Red eTap drivetrain. Installing the chainrings is essentially the reverse of removing the OEM chainrings and re-uses the original hardware. There are built in markers to help properly orient the chainrings while installing which depends on which version of the chainrings you purchase. With our SRAM Red setup, there is a hidden bolt setup with a bolt behind the crank arm which came with a new bolt. It takes a bit of patience to line up the bolts when you’re installing them but once you have a few started it’s quick and easy. We also swapped out our KMC Aurora chain per absoluteBLACK’s recommendation to avoid any shifting issues due to a worn out chain.
If you are replacing the outer ring you’ll very likely need to adjust your front derailleur as the oval design pushes the chain quite a bit higher than a circular chainring. On our bike the original derailleur position would actually rub against the chain so we had to move the derailleur upward and fine tune the angle. Despite how loop-sided the oval chainrings visually look, once the derailleur is properly positioned the bike shifted and sounded just like the OEM setup with fast and precise shifting.
THE VERDICT
Overall, we found the absoluteBLACK Oval Chainrings to be beautiful chainrings with a subtle but noticeable improvement while climbing. As with all of absoluteBLACK’s products, the chainrings have intricate CNC detailing and a premium anodized finish that are a big visual upgrade from OEM setups. Despite how odd the oval chainrings look while spinning, we only felt a subtle difference while climbing with a smoother pedal stroke. The only negatives with the setup is that the oval outer chainring requires front derailleur adjustments and that absoluteBLACK does not offer any color options except for a Dura-Ace specific PVD finish. Even if you don’t feel a big difference with the oval setup, the intricate CNC detailing and competitive pricing is enough to make them a nice upgrade for any cyclist.
Disclaimer: The product for this review was provided by absoluteBLACK. The views expressed on this website are solely those of the authors and are here to help people make an informed choice before a purchase. The authors or the blog itself does not get any monetary compensation from the product manufacturer or third-party websites/vendor links that are posted here.