Bicycle handlebar having different directional stiffnesses

Abstract

An elongate, tubular handlebar can include a laterally extending central mounting portion, a tubular left body section extending laterally from one side of the mounting portion a tubular right body section extending laterally from the other side of the mounting portion. The right body section may have an elongate, tubular right control portion extending laterally from an inboard end to an outboard end and configured to support a generally laterally extending grip and a right transition portion having a non-circular, transition cross-sectional shape at a first location defining a first width measured in a first direction and a second width that is greater than the first width and is measured in a second direction. Whereby right body section has a first stiffness in the first direction and a second stiffness that is greater than the first stiffness in the second direction.

What is claimed is: 
     
         1 . An elongate, tubular handlebar connectable to a steerer tube of a bicycle, the handlebar comprising:
 a) a laterally extending central mounting portion configured to be connected to the steerer tube of a bicycle and extending along a mounting axis;   b) a tubular left body section extending laterally from one side of the mounting portion and comprising a left control portion configured to support a grip and a left transition portion extending laterally between the left control portion and the mounting portion;   c) a tubular right body section extending laterally from the other side of the mounting portion and comprising:
 i. an elongate, tubular right control portion extending laterally from an inboard end to an outboard end and configured to support a generally laterally extending grip; and 
 ii. a right transition portion extending laterally between the inboard end of the right control portion and the mounting portion and having a non-circular, transition cross-sectional shape at a first location defining a first width measured in a first direction extending in a plane that is orthogonal to the mounting axis and a second width that is greater than the first width and is measured in a second direction that is measured in the plane and that is at an angle relative to the first direction, wherein when the handlebar is connected to the steerer tube forces exerted in the second direction exert steering forces on the steering tube; 
   
       whereby when an input force is applied to the right control portion in the first direction the right body section has a first stiffness and when the input force is applied to the right control portion in the second direction the right body section has a second stiffness that is greater than the first stiffness. 
     
     
         2 . The handlebar of  claim 1 , wherein the mounting portion has a substantially circular cross-sectional shape having a mounting diameter and the right control portion has a substantially circular cross-sectional shape having a control diameter that is less than the mounting diameter, and wherein the first width and the second width are each greater than the control diameter and less than the mounting diameter. 
     
     
         3 . The handlebar of  claim 2 , wherein the right transition portion further comprises a second non-circular, transition cross-sectional shape at a second location that is laterally spaced apart from the first location and that defines a third width measured in the first direction that is less than the first width and a fourth width measured in the second direction that is less than the third width and the second width. 
     
     
         4 . The handlebar of  claim 1 , wherein the right transition portion has an inboard end adjacent the mounting portion and an outboard end adjacent the right control portion and wherein the first location is disposed substantially equally between the inboard end and the outboard end 
     
     
         5 . The handlebar of  claim 4 , wherein the right transition zone comprises a first wall thickness at the inboard end and greater second wall thickness at the outboard end. 
     
     
         6 . The handlebar of  claim 4 , wherein the right transition portion has a substantially circular cross-sectional shape at the inboard end and at the outboard end. 
     
     
         7 . The handlebar of  claim 1 , wherein the second direction is substantially orthogonal to the first direction. 
     
     
         8 . The handlebar of  claim 1 , wherein the right transition portion is configured so that when the mounting portion is connected to the steerer tube of a bicycle the first direction is oriented within about 45 degrees of an axis of rotation of the steerer tube. 
     
     
         9 . The handlebar of  claim 1 , wherein the right transition portion is configured so that when the mounting portion is connected to the steerer tube of a bicycle the first direction is oriented within about 30 degrees of a vertical plane. 
     
     
         10 . The handlebar of  claim 1 , wherein the right transition portion is configured so that when the mounting portion is connected to the steerer tube of a bicycle the second direction is within about 45 degrees of a horizontal plane. 
     
     
         11 . The handlebar of  claim 1 , wherein the second stiffness is between about 110% and 150% of the first stiffness. 
     
     
         12 . The handlebar of  claim 1 , wherein the first stiffness is between about 5.5 and about 7.5 (kg/mm) and the second stiffness is between about 8 and about 10 (kg/mm). 
     
     
         13 . The handlebar of  claim 1 , wherein the first width is between about 15mm and about 30mm and wherein the second width is between about 25mm and about 35mm. 
     
     
         14 . The handlebar of  claim 1 , wherein the first width is between about 60% and about 90% of the second width. 
     
     
         15 . The handlebar of  claim 1 , wherein the right transition portion has a substantially elliptical transition cross-sectional shape at the first location and has an eccentricity calculated as 
       
         
           
             
               
                 1 
                 - 
                 
                   
                     ( 
                     
                       first width 
                       second width 
                     
                     ) 
                   
                   2 
                 
               
             
           
         
       
       that is between about 0.5 and about 0.8 at the first location. 
     
     
         16 . The handlebar of  claim 1 , wherein the left transition portion comprises a third non-circular, transition cross-sectional shape at a third location defining a fifth maximum width measured in the first direction and a sixth width that is greater than the fifth width and is measured in the second direction;
 whereby when an input force is applied to the left control portion in the first direction the left body section has a third stiffness and when the input force is applied to the left control portion in the second direction the left body section has a fourth stiffness that is greater than the third stiffness.   
     
     
         17 . The handlebar of  claim 1 , wherein a distance between an outboard end of the left control portion and the outboard end of the right control portion in the lateral transverse direction defines a handlebar length, and wherein the handlebar length is between about 700 mm and about 900 mm. 
     
     
         18 . The handlebar of  claim 1 , wherein the right transition portion has a transition length in the transverse direction that is between about 15% and about 25% of the handlebar length. 
     
     
         19 . The handlebar of  claim 18 , wherein the right control portion has a control length in the transverse direction that is greater than the transition length. 
     
     
         20 . The handlebar of  claim 1 , wherein the right control portion extends along a right control axis that intersects the mounting axis at a sweep angle that is between about 0 and about 15 degrees.