FWIW I did those hills on 48/19 (a little smaller than 47/18) with ease so I'm sure you'll be ok with the 18t on, it's still best to learn to spin.
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FWIW I did those hills on 48/19 (a little smaller than 47/18) with ease so I'm sure you'll be ok with the 18t on, it's still best to learn to spin.