Only the best for your Shimano cranks: the oval Road R9100/R8000 chainrings by absoluteBLACK
absoluteBLACK Premium Shimano 110/4 bcd compatible oval chainrings are designed for new type of Shimano cranks Dura-Ace 9100 & Ultegra 8000 only. These are some of the finest oval chainrings on the market in terms of shifting, smoothness of pedaling and manufacturing quality. (They can be also retrofitted to 9000 and 6800 cranks). 10/11/12spd compatible.
absoluteBLACK was founded in 2008 by a former Trek Bicycle engineer. The design office is based in London, UK. absoluteBLACK products are manufactured in Poland from German raw material, then skillfully anodized in the United Kingdom. Truly European products. Their oval chainrings excel with each chainring size having its own ovality and timing.
Mount: 110 mm bolt circle diameter, 4-arm asymmetrical
Teeth: 34 t, 36 t, 38 t, 39 t, 50 t, 52 t, 53 t
Gearing: 2x10-speed, 2x11-speed, 2x12-speed
Type: oval 6.5 % (34 t), 11.4 % (36/38/39 t), 10 – 11.2 % (50/52/53 t)
Material: aluminium (7075)
Combinations: 34-50 t, 36-52 t, 38-52 t, 39-53 t*
* If you wish to use other configuration it will also work, but shifting will be slower and may require more " adjustments" of front derailleur to be acceptable. Also remember that front derailleur can only accept max 16 t difference between 2 chainrings - this is how Shimano and SRAM designed them.
- for Shimano Dura Ace R9100 and Ultegra R8000
- can also retrofit 9000 and 6800 cranks but use bolt covers (Dura Ace, Ultegra) for best appearance
- Di2 compatible
- designed using 3D CAD software, CNC machined, anodized
- long-lasting construction (5 mm)
- smoother, more efficient pedaling action, helps you climb easier and faster
- reduced stress on knees
- 6 up-shifting ramps, 12 down-shifting points
- excellent weight to strength ratio
- reduces chainring/cog shifts by at least 15 %
- ovality and timing (108-110.5°) optimised for each size separately (TDC technology, top dead center)
- for outer chainring please order long bolts or bolt covers (Dura Ace, Ultegra)
Why absoluteBLACK oval chainrings work
Oval rings work with the natural human physiology. Oval chainrings maximise the part of the stroke where power is produced and minimise resistance where it isn't. As a direct consequence, oval rings enhance a cyclist’s ability to spin with a smoother power delivery and feel easier on legs while climbing.
You will actually feel your pedal stroke to be more " round" with an oval chainring than with a round chainring.
Why using oval chainrings matters
In comparison to round chainrings, when using oval chainrings, human legs utilise more muscle groups - but each of them to lesser degree. The overall load from pedalling an oval chainring is spread over a greater muscle mass, which reduces the peak loads on knee joints.
This has three key benefits: firstly, it gives you the feeling of fresher and more relaxed legs. Secondly, it allows you to achieve higher average speed riding uphill. Thirdly, spreading the pedalling load over more muscles reduces the risk of cramp, even when riding hard. This means your overall enjoyment of the ride is enhanced. On MTB side in addition rear tyre traction improves greatly on loose and slippery terrain when using oval. Climbing becomes much easier in demanding terrain.
- 1 x absoluteBLACK Road R9100 & R8000 oval chainring
-black / 34 tooth : 31 g
-black / 36 tooth : 37 g
-black / 38 tooth : 41 g
-black / 39 tooth : 42 g
-black / 50 tooth : 120 g
-black / 52 tooth : 137 g
-black / 53 tooth : 139 g