When all you hear is the purring of the front wheel on the tarmac and the satisfying “clunk” as the rear derailleur perfectly positions the chain down a sprocket, when the chain is silent as it strains against the gears and your bike responds to your every whim, when the previous days of cycling put you in good shape and you are going at a good pace without an apparent effort, then you are one with the machine, and all is right with the world, and you feel you could fly.