Rain grooves

Rain grooves are narrow channels cut into the surface of some concrete roads and bridges, mostly in North America, to drain water and reduce aquaplaning for cars. When they run in the direction of travel, motorcycle tyres can follow the grooves, so the bike feels as if it is wandering or wobbling slightly.

The feeling is unsettling but rarely dangerous. Keep a relaxed grip on the bars, hold a steady throttle and line, and let the bike move a little under you instead of fighting it. Tyres with a squarer or worn profile tend to track grooves more.