The Quarq DFour DUB Power Meter is designed for users of a Shimano crankset that want to add a power meter while maintaining their Shimano drivetrain. However, there are some things you should know regarding chainrings, cranks and bottom brackets. Let’s dig in!
The DFour uses a 110 BCD, 4-bolt spider so you can use your Shimano chainrings on it. The power meter is designed for use with Shimano DURA-ACE 9100 chainrings. Other Shimano 11- and 12-speed chainrings will work, however they will not match the shape or color of the power meter as nicely. Shimano 12-speed rings in particular, while compatible, have a bit of a funny look when mounted to the DFour…just something to be aware of.
Please note that you must replace your entire crankset with the new DFour crankset (power meter spider plus new Quarq DZero crank arms). This is because Shimano road cranksets have an integrated right-side crank arm and spider (the spider and crank arm are one solid piece). Therefore, you cannot physically install just the DFour Power Meter Spider on your Shimano crankset. Rather, you must purchase the DFour power meter spider plus the Quarq DZero DUB Crank Arms. On our product page for the DFour power meter, you can bundle the power meter with crank arms by simply selecting the crank arm length that you need.
Unfortunately the DFour isn’t plug and play if you are running a Shimano road crankset. This is because your Shimano crankset uses a 24 mm spindle whereas the Quarq DFour uses a 29 mm DUB spindle. Therefore, you must replace your Shimano bottom bracket with a SRAM DUB Bottom Bracket.
If changing your bottom bracket sounds like too much work, we have two great alternatives.
Like the Quarq DFour, the power2max and Siegyi are new cranksets (power meter spider and crank arms). However, with these options, you don’t have to change your bottom bracket. You can order the power2max or Sigeyi in the same 24 mm spindle size making it a direct replacement for your Shimano crankset. In addition, as with the DFour, you can use your current Shimano chainrings on it (just be sure to select the 110 4-Bolt Shimano BCD option). Both the power2max and Sigeyi make wonderful power meters. They measure both left and right leg power, are reasonably priced and are as good as it gets in terms of accuracy, consistence and reliability.