Yes, it slows me down as well, but mostly if I go uphill. I can hold 22-25 pmph on flats without a problem. Depending on the wind strength it can slow me down to 17-20. Going uphill against wind is not fun at all. In places where I hold 14-15 slows me down to 10-12. But if the wind is really nasty - I don't ride at all. I hate those AZ tumbleweeds fying in my face.