Surly is owned by and shares facilities with Quality Bicycle Products (QBP). The company is well known in bicycle messenger and single-speed culture and helped establish the Single Speed World Championship (SSWC). Surly specializes in steel bicycle frames. Frames are made in Taiwan from 4130 cromoly steel. Distinctive components made by Surly include the Dingle cog, cranksets with separately detachable spiders, reversible chain tensioner, and the "Large Marge" an unusually wide bicycle rim. Surly also sells lifestyle items such as wool jerseys and flasks bearing the Surly logo. Frame Models
In 2005, Surly began selling the Pugsley, the first mass-produced mountain bike with extremely large volume tires, up to 4 inches wide, for deep snow and sand riding. The front and rear wheels share a common hub size and can be interchanged, allowing for additional gearing combinations. Noted bicycle technical authority Sheldon Brown said, "Pugsley is, in its way, as revolutionary as the original mountain bikes were in the early 1980s." Bicycling Magazine wrote, "It's not ideal for everyday use, but it can handle a wide variety of demands and conditions well."
