Electronic Derailleur - Front
Your front derailleur will pick up the chain and move it between your chainrings, based on your selection. So if a big hill is coming up, switch to the smaller ring and increase your cadence - equally if you've just crested a big hill you can engage the big ring and hit your top speed on the downslope! Electronic front derailleurs will as with the rest of the electronic ranges offer precise shifting, leading to sublime control of your ride.
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