Shimano road cranksets (image below) have an integrated spider. This means the drive-side crank arm and spider portion of the crankset are one solid piece. Therefore, it is physically impossible to install a spider-based power meter such as the Sigeyi on these cranksets.
Sigeyi ROTOR ALDHU Road Power Meter Crankset
Therefore, for Shimano users that would like to use a Sigeyi power meter, we suggest the Sigeyi ROTOR ALDHU Road Power Meter Crankset.
This is a spider-based power meter that comes on a ROTOR ALDHU crankset. In addition to being a great all-around power meter, here’s why it’s great for Shimano users:
1) If you select one of the 24MM ALDHU Crank sizes, this power meter will come with the same spindle size as your current Shimano crankset and will fit your bottom bracket without any changes. This makes installation a breeze.
2) In addition, if you select the 110 4-Bolt BCD option, you can also use your current Shimano chainrings on it.
This makes is a direct replacement for a Shimano road crankset.