The riff to the Beatles’ “Day Tripper” is one that everybody should know. It’s a little tougher to play than you might think, and its syncopation requires you to be on the ball in order to keep it locked in. Yes, you could get away with playing this lick with all downstrokes or however you want, but IMO it makes a great exercise in alternate picking, and feeling rhythm in your picking hand.
What makes this lick rhythmically interesting is that it has a variety of note lengths, and a lot of notes that fall on upbeats and are held across a beat. In other words, it’s syncopated. It is important to make sure you feel each beat with a downward motion of your right hand, even when you’re not actually playing a note on that beat. Watch the video for a demonstration.