Clackamas Cycle world employee began smelling and seeing smoke shortly before Noon Thursday at their store located at 11493 SE 82nd ave.
No one was injured as the employee quickly activated 911 after fleeing the structure.
Firefighters found a fire on the exterior of the building that had extended into the wall and attic space.
By quickly attacking it from both inside and out they were able to minimize the damage.
While still under investigation it is thought to have started after someone was burning weeds with a propane torch.