It’s a good question and unfortunately the answer is no.
Shimano road cranksets have an integrated right-side crank arm and spider, so you cannot physically install a spider-based power meter on a road crankset. Therefore, in order to run the Quarq DFour DUB Power Meter, you must change out your crankset.
Specifically, the Quarq DFour requires the use of Quarq DZero DUB Crank Arms. On our product page for the DFour power meter, you can easily bundle the power meter with crankarms by simply selecting the crank arm length that you need. Please note, in order to run this power meter, you also need a SRAM DUB Bottom Bracket.
If changing your bottom bracket sounds like more work than you would like to go through, we have a great alternative.
Like the Quarq DFour, the power2max is a new crankset (power meter spider and crank arms). However, with the power2max, you don’t have to change your bottom bracket. You can order the power2max in the same 24 mm spindle size your Shimano crankset uses 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). power2max makes wonderful power meters. They measure both left and right leg power, are reasonably priced and are as good as it gets in terms of reliability.