Originally Posted by
Jarrett2
The cool thing they hinted at is if your RDR battery goes dead on a ride, you can pick a front ring, then move the battery to the RDR and get home.
Di2 essentially accomplishes the same result. If you forget to recharge it, the FD, which takes more power, is disabled, but you retain the ability to shift on the rear, until the battery's gone. It will work I this mode for at least 40 miles (don't ask me how I know this.
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