Yes, you can; and even I can. The adjustment is quite simple.
I just got a new evelo, and after about a month, I noticed its beautiful disc brakes were making a pretty loose response to my squeezes. This is because new cable stretches a bit after being used. On a new bike, this is typical.
So, here’s what you do. (These instructions were provided to me by the wonderful evelo support folks.) First, loosen the lock ring by unscrewing it so there is a slight gap between it and the actual lever mount. Then, unscrew the adjustment barrel a turn or so. This has the effect of lengthening the cable housing and pulling on the cable a bit. Check out the head picture to this blog.
Test by squeezing the lever, then lifting the tire off the ground and spinning it. Ideally, you should be able to adjust it so the lever won’t reach the handlebar grip when pulled hard, yet the wheel spins freely without resistance when the brake is released.
When you find the proper adjustment, re-tighten the lock ring to hold the barrel in this new position.
Finally, here are a few additional pictures for reference (you can take up more cable slack at the caliper itself):