A flow restrictor is provided for a lubrication circulation system. The flow restrictor comprises a body configured to obstruct a flow of lubricant within the lubricant circulation system. The body has one or more through holes communicating with upstream and downstream portions of the lubrication circulation system. Each of the one or more holes has a cross-sectional area sufficiently small, and a length sufficiently long, to prevent turbulent lubricant flow therethrough at temperatures below a first predetermined reference temperature. The one or more holes have sufficient aggregate cross-sectional area to allow a desired lubricant flow rate through the body at temperatures at or above a second predetermined reference temperature.