Yes, I do get sweat running into my eyes, and it burns a bit, definitely uncomfortable. What I did on my longish rides was to wear a kind of sweat band thingy under my helmet. On one ride when it was kinda cold, I wore this thing like a scarf for both sweat wicking and warmth. Last time I wore it the weather was hot and muggy, so I rolled it up to the width of a sweat band and wore it just below the edge of my helmet. I got it at REI. It's called "Buff". Comes in many colors and patterns. Oh, and extra benefit ... you can unroll it into a scarf style and cover the "helmet hair" when you stop for a coffee break.