Background: I've been riding 42x16 for about a year on 27 inch, thicker tires on old heavier wheels. I recently purchased a new wheel set (700c and MUCH lighter and thinner). I decided that I should buy a 15t cog because 16 had gotten so I was spinning more than I would like to and couldn't get past a certain speed. So I've switched out the wheel set and I'm riding this gear and it feels like I'm pushing really hard up hills and from starts. My question is: How long should I expect this transition to last? Will it get better? Will my legs get stronger, is this a gear I should be able to run in a hilly neighborhood?

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