I've done the same thing a number of times. A few years ago, I had a bike built up from scratch. I never felt very fast on it. A couple of years later, I moved some of the components from that bike over to my other road bike and, again, I started feeling really slow. Finally, we realized that the rear break wasn't staying centered. It didn't even take a topple or anything to get it wonky. It would just spontaneously move. We fixed it, but not before I had a number of rides that just kind of sucked.
Live with intention. Walk to the edge. Listen hard. Practice wellness. Play with abandon. Laugh. Choose with no regret. Continue to learn. Appreciate your friends. Do what you love. Live as if this is all there is.
--Mary Anne Radmacher