Studded tires are believed to be a significant cause of road damage to state highways. ODOT suggests that studs exclusively be used on icy roads. Oregon Studded Tires: Laws and Initiatives.

Many proposals have been made to make cycling around the city safer, because Portland bicycle accident attorneys see hundreds of clients each year who have been injured by other road users. Frequently, this is because of unsafe cycling lanes or … Oregon's last estimate, based on a 2014 study, put annual damage at $8.5 million. … Oregonians with studded traction tires on their cars or trucks won’t have to remove them next week after all, state officials said Monday. Vehicle owners in Oregon will not be required to remove studded tires until May 1, a month later than the normal deadline, the Oregon Department of Transportation decided Monday. Oregon extends deadline to remove studded tires, cites coronavirus pandemic Oregonians with studded traction tires on their cars or trucks won’t have to remove them next week after all. Studs are designed for very specific road conditions (and specific tires), and can legally only be used from Nov. 1 to March 31 in Oregon.

Portland has long been known as one of the most bike-friendly cities in the entire country. Being caught with studded tires before or after the designated dates is a Class C violation, and can result in a fine of up to $200.